CN116505474A - Battery Protection Circuits and Electronics - Google Patents

Abstract

The application provides a battery protection circuit and electronic equipment, wherein, battery protection circuit includes power detection circuitry, first protection circuit, first logic control circuit and first switch circuit, first logic control circuit can control first switch circuit and turn off when power detection circuitry output first level signal, and at power detection circuitry output second signal, first protection circuit output discharge protection signal, trigger battery protection circuit and get into discharge protection state, and battery protection circuit is in discharge protection state, first logic control circuit can control first switch circuit and keep turning off, like this, when power detection circuitry detects power signal, battery protection circuit just gets into automatically and locks in the off state, the equipment trouble problem that probably causes because battery voltage is unstable when having avoided battery protection circuit to power on.

Description

Battery Protection Circuits and Electronics

technical field

The present application relates to the technical field of battery protection, in particular to a battery protection circuit and electronic equipment.

Background technique

With the rapid development of electronic technology, electronic devices are widely used in daily life. The battery protection circuit is an important part of the electronic equipment, which is connected to the battery and can ensure the safety of the battery when the battery supplies power to the electronic equipment.

In the prior art, during the assembly process of the battery protection circuit, the load circuit, and the battery, the battery may power the load circuit through the battery protection circuit. The problem of power-on and power-off makes the battery protection circuit and load circuit may repeatedly withstand the impact of high current, which may cause logic errors in the battery protection circuit and load circuit, and even damage the battery protection circuit in severe cases, which may easily lead to failure of electronic equipment .

Contents of the invention

The present application provides a battery protection circuit and electronic equipment, which are used to solve the problem of equipment failure that may exist due to unstable battery voltage during the assembly process of the battery protection circuit connected with the load circuit and the battery.

In a first aspect, the present application provides a battery protection circuit, including: a power detection circuit, a first protection circuit, a first logic control circuit, and a first switch circuit;

The battery protection circuit includes a power supply terminal, a power ground terminal and a system terminal; the power supply terminal is connected to the first terminal of the power detection circuit, and the second terminal of the power detection circuit is connected to the power ground terminal , the output end of the power detection circuit is respectively connected to the first input end of the first protection circuit and the first input end of the first logic control circuit, and the output end of the first protection circuit is connected to the first input end of the first protection circuit. The second input terminal of a logic control circuit is connected, the output terminal of the first logic control circuit is connected to the control terminal of the first switch circuit, and the first terminal of the first switch circuit is connected to the ground terminal of the power supply or The power supply terminal is connected, and the second terminal of the first switch circuit is connected to the system terminal;

The first logic control circuit is used to control the first switch circuit to turn off when the power detection circuit outputs a first level signal, and when the power detection circuit outputs a second signal, the first protection circuit Outputting a discharge protection signal, the battery protection circuit enters a discharge protection state, and when the battery protection circuit is in the discharge protection state, the first logic control circuit controls the first switch circuit to keep off.

In a possible design of the first aspect, the battery protection circuit further includes a latch circuit;

The first end of the latch circuit is connected to the output end of the power detection circuit, and the second end of the latch circuit is connected to the first protection circuit;

The latch circuit enters a locked state when the power detection circuit outputs a second signal, and the latch circuit keeps outputting a protection trigger signal in the locked state, and the protection trigger signal is used to make the first protection circuit output discharge protection signal.

In a possible design of the first aspect, the first protection circuit includes an over-discharge voltage protection circuit, the input end of the over-discharge voltage protection circuit is connected to the power supply end, and the battery protection circuit further includes a first Three switch circuits and a second logic control circuit;

The control terminal of the third switch circuit and the first input terminal of the second logic control circuit are both connected to the over-discharge voltage protection circuit, and the first terminal of the third switch circuit is connected to the second logic control circuit. The second input terminals of the circuit are all connected to the system terminal, and the output terminals of the second logic control circuit are respectively connected to the over-discharge voltage protection circuit and the latch circuit;

When the first terminal of the first switch circuit is connected to the ground terminal of the power supply, the second terminal of the third switch circuit is connected to the power supply terminal, or, the first terminal of the first switch circuit is connected to the ground terminal of the power supply. When the power supply end is connected, the second end of the third switch circuit is connected to the power ground end;

When the over-discharge voltage protection circuit outputs a discharge protection signal, the third switch circuit is turned on, the second logic control circuit outputs a first dormancy signal, and the over-discharge voltage protection circuit receives the first dormancy signal Continuously output the discharge protection signal, and the latch circuit releases the locked state when receiving the first dormancy signal.

Optionally, the over-discharge voltage protection circuit includes an over-discharge voltage protection unit, a delay protection circuit, a latch unit and a logic gate circuit;

As an example, the output terminal of the latch circuit is connected to the first input terminal of the logic gate circuit, and the output terminal of the over-discharge voltage protection unit is connected to the delay protection circuit and the latch unit respectively. It is connected with the second input terminal of the logic gate circuit, the delay protection circuit is connected with the third input terminal of the logic gate circuit through the latch unit, and the output terminals of the logic gate circuit are respectively connected with the The first input end of the second logic control circuit, the control end of the third switch circuit, and the second input end of the first logic control circuit are connected, and the output ends of the second logic control circuit are connected to the lock respectively. The storage circuit, the over-discharge voltage protection unit and the delay protection circuit are connected; wherein, when the logic gate circuit receives a protection trigger signal, the logic gate circuit outputs a discharge protection signal, and the third switch circuit Turn on the conduction, the first logic control circuit controls the first switch circuit to keep off, the voltage of the system terminal is pulled up, and the second logic control circuit outputs according to the discharge protection signal and the voltage signal of the system terminal A first dormancy signal, the first dormancy signal is used to enable the discharge overvoltage protection function of the over-discharge voltage protection unit, shield the delay function of the delay protection circuit, and release the lock state of the latch circuit ;

As another example, the output terminals of the latch circuit are respectively connected to the over-discharge voltage protection unit and the delay protection circuit, and the output terminals of the over-discharge voltage protection unit are respectively connected to the delay protection circuit , the latch unit is connected to the first input end of the logic gate circuit, the delay protection circuit is connected to the second input end of the logic gate circuit through the latch unit, and the logic gate circuit is connected to the second input end of the logic gate circuit The output terminals are respectively connected to the first input terminal of the second logic control circuit, the control terminal of the third switch circuit and the second input terminal of the first logic control circuit, and the output of the second logic control circuit Terminals are respectively connected to the latch circuit and the over-discharge voltage protection unit; wherein, when the over-discharge voltage protection unit receives a protection trigger signal, the over-discharge voltage protection unit outputs a first protection signal, and the over-discharge voltage protection unit outputs a first protection signal. The delay function of the delay protection circuit is shielded, the latch unit enters the locked state via the delay protection circuit, and in the locked state, the latch unit continues to output the delayed arrival signal, and the logic gate circuit according to The first protection signal and the delayed arrival signal output a discharge protection signal, the third switch circuit is turned on, the first logic control circuit controls the first switch circuit to keep off, and the voltage at the system end is pulled up, so The second logic control circuit outputs a first dormancy signal according to the discharge protection signal and the voltage signal of the system terminal, and the first dormancy signal is used to enable the discharge overvoltage protection function of the over-discharge voltage protection unit and release the locked state of the latch circuit.

In a possible design of the first aspect, the first protection circuit includes a discharge overcurrent protection circuit, the input end of the discharge overcurrent protection circuit is connected to the system end, and the battery protection circuit further includes a fourth switch circuit and voltage detection circuit;

The control terminal of the fourth switch circuit and the first input terminal of the voltage detection circuit are both connected to the discharge overcurrent protection circuit, and the first terminal of the fourth switch circuit is connected to the second input terminal of the voltage detection circuit. The input ends are all connected to the system end, and the output ends of the voltage detection circuit are respectively connected to the discharge overcurrent protection circuit and the latch circuit;

When the first terminal of the first switch circuit is connected to the ground terminal of the power supply, the second terminal of the fourth switch circuit is connected to the ground terminal of the power supply, or, the first terminal of the first switch circuit is connected to the ground terminal of the power supply. When the power supply terminal is connected, the second terminal of the fourth switch circuit is connected to the power supply terminal;

When the discharge overcurrent protection circuit outputs a discharge protection signal, the fourth switch circuit is turned on, and the voltage detection circuit outputs a discharge overcurrent hold when the discharge overcurrent protection circuit does not enter the discharge overcurrent protection state signal, the discharge overcurrent holding signal is used to make the discharge overcurrent protection circuit continuously output the discharge protection signal, and the voltage detection circuit outputs the discharge overcurrent protection signal when the discharge overcurrent protection circuit enters the discharge overcurrent protection state signal, and when the latch circuit receives the discharge overcurrent protection signal, the lock state is released.

Optionally, the discharge overcurrent protection circuit includes a discharge overcurrent protection unit, a delay protection circuit, a latch unit and a logic gate circuit;

As an example, the output end of the latch circuit is connected to the first input end of the logic gate circuit, and the output end of the discharge overcurrent protection unit is respectively connected to the delay protection circuit, the latch unit It is connected with the second input terminal of the logic gate circuit, the delay protection circuit is connected with the third input terminal of the logic gate circuit through the latch unit, and the output terminals of the logic gate circuit are respectively connected with the The first input end of the voltage detection circuit, the control end of the fourth switch circuit, and the second input end of the first logic control circuit are connected, and the output end of the voltage detection circuit is respectively connected to the latch circuit, the The discharge overcurrent protection unit is connected to the delay protection circuit; wherein, when the logic gate circuit receives a protection trigger signal, the logic gate circuit outputs a discharge protection signal, and the fourth switch circuit is turned on, The first logic control circuit controls the first switch circuit to keep off, the voltage of the system terminal rises, and when the voltage of the system terminal is less than or equal to the discharge overcurrent threshold voltage, the discharge overcurrent protection unit does not enter the discharge In the overcurrent protection state, the voltage detection circuit outputs a discharge overcurrent hold signal. When the voltage at the system terminal is greater than the discharge overcurrent threshold voltage, the discharge overcurrent protection unit enters the discharge overcurrent protection state, and the voltage detection circuit Outputting a discharge overcurrent protection signal, wherein the discharge overcurrent hold signal is used to enable the discharge overcurrent protection function of the discharge overcurrent protection unit and shield the delay function of the delay protection circuit, the latch The unit enters the locked state through the delay protection circuit and continuously outputs the delayed arrival signal in the locked state, and the logic gate circuit keeps outputting the discharge protection signal, and the discharge overcurrent protection signal is used to release the latch circuit. lock state and clear the latch;

As another example, the output terminals of the latch circuit are respectively connected to the discharge overcurrent protection unit and the delay protection circuit, and the output terminals of the discharge overcurrent protection unit are respectively connected to the delay protection circuit and the delay protection circuit. The latch unit is connected to the first input terminal of the logic gate circuit, the delay protection circuit is connected to the second input terminal of the logic gate circuit through the latch unit, and the output terminal of the logic gate circuit respectively connected to the first input terminal of the voltage detection circuit, the control terminal of the fourth switch circuit and the second input terminal of the first logic control circuit; wherein, when the discharge overcurrent protection unit receives protection When the signal is triggered, the discharge overcurrent protection unit outputs the first protection signal, the delay function of the delay protection circuit is shielded, and the latch unit enters the lock state through the delay protection circuit, and in the lock state , the latch unit continues to output a delayed arrival signal, the logic gate circuit outputs a discharge protection signal according to the first protection signal and the delayed arrival signal, the fourth switch circuit is turned on, and the first logic control circuit Control the first switch circuit to keep off, the voltage at the system end increases, and when the voltage at the system end is less than or equal to the discharge overcurrent threshold voltage, the voltage detection circuit outputs a discharge overcurrent hold signal, and at the system end When the voltage is greater than the discharge overcurrent threshold voltage, the voltage detection circuit outputs a discharge overcurrent protection signal, wherein the discharge overcurrent hold signal is used to enable the discharge overcurrent protection function of the discharge overcurrent protection unit, the The discharge overcurrent protection signal is used to release the latch state of the latch circuit and clear the latch.

Optionally, the first protection circuit includes a discharge overcurrent protection unit, a delay protection circuit, a latch unit, a first logic gate circuit, and a second logic gate circuit, and the battery protection circuit further includes a fourth switch circuit;

The output terminal of the latch circuit is connected to the first input terminal of the second logic gate circuit, the input terminal of the discharge overcurrent protection unit is connected to the system terminal, and the output terminal of the discharge overcurrent protection unit respectively connected to the delay protection circuit, the latch unit and the first input end of the second logic gate circuit, the delay protection circuit through the latch unit and the first logic gate circuit The second input terminal is connected, the output terminal of the first logic gate circuit is connected with the second input terminal of the second logic gate circuit and the latch circuit respectively, and the output terminal of the second logic gate circuit is connected with the latch circuit. The control end of the fourth switch circuit is connected;

When the first terminal of the first switch circuit is connected to the ground terminal of the power supply, the second terminal of the fourth switch circuit is connected to the ground terminal of the power supply, or, the first terminal of the first switch circuit is connected to the ground terminal of the power supply. When the power supply terminal is connected, the second terminal of the fourth switch circuit is connected to the power supply terminal;

When the second logic gate circuit receives a protection trigger signal, the second logic gate circuit outputs a discharge protection signal, the fourth switch circuit is turned on, and the first logic control circuit controls the first switch circuit to maintain turn off, the voltage of the system terminal rises, so that the discharge overcurrent protection unit outputs the first protection signal, and the latch unit enters the locked state through the delay protection circuit, and in the locked state, the latch The unit continuously outputs the delayed arrival signal, the first logic gate circuit outputs the discharge overcurrent protection signal according to the first protection signal and the delayed arrival signal, and the second logic gate circuit continuously outputs the discharge protection signal, so When the above-mentioned latch circuit receives the discharge overcurrent protection signal, the latch state is released.

In a possible design of the first aspect, the first protection circuit includes a discharge protection circuit, a delay protection circuit, and a logic gate circuit;

The first input end of the discharge protection circuit is connected to the second end of the latch circuit, and the output end of the discharge protection circuit is respectively connected to the delay protection circuit and the first input end of the logic gate circuit , the delay protection circuit is also connected to the second end of the latch circuit and the second input end of the logic gate circuit;

When the latch circuit outputs a protection trigger signal, the discharge protection circuit outputs a first protection signal, and the delay function of the delay protection circuit is shielded, and the logic gate circuit outputs a discharge protection signal.

In a possible design of the first aspect, the first protection circuit includes a discharge protection circuit, a delay protection circuit, and a logic gate circuit;

The input end of the discharge protection circuit is connected to the power supply end or the system end, and the output end of the discharge protection circuit is respectively connected to the input end of the delay protection circuit and the first input of the logic gate circuit. terminal connection, the output terminal of the delay protection circuit is connected with the second input terminal of the logic gate circuit, the third input terminal of the logic gate circuit is connected with the output terminal of the latch circuit, and the logic gate circuit The output terminal of the circuit is connected with the first logic control circuit;

When the latch circuit outputs a protection trigger signal, the logic gate circuit outputs a discharge protection signal.

In a possible design of the first aspect, the first protection circuit includes a discharge protection circuit, a zero-delay protection circuit, a delay protection circuit, a first latch unit, a second latch unit, and a third logic gate circuit and a fourth logic gate circuit;

The first input end of the discharge protection circuit is connected to the second end of the latch circuit, and the output end of the discharge protection circuit is respectively connected to the zero-delay protection circuit, the delay protection circuit, the second A latch unit, the second latch unit, and the third logic gate circuit are connected, and the output end of the latch circuit is also connected with the zero-delay protection circuit and the delay protection circuit, and the The zero-delay protection circuit is connected to the first latch unit, the delay protection circuit is connected to the second latch unit, and both the first latch unit and the second latch unit are connected to the A fourth logic gate circuit is connected, the fourth logic gate circuit is connected to the third logic gate circuit, and the third logic gate circuit is connected to the first logic control circuit;

When the latch circuit outputs a protection trigger signal, the discharge protection circuit outputs a first protection signal, the zero-delay protection circuit is triggered to work, the delay protection circuit does not work, and the first latch The unit enters the locked state without delay, and in the locked state, the first latch unit continues to output the first intermediate signal, the fourth logic gate circuit receives the first intermediate signal and continues to output the delayed arrival signal, and the first latch unit continues to output the delayed arrival signal. The three logic gate circuit outputs a discharge protection signal according to the delayed arrival signal and the first protection signal.

In a possible design of the first aspect, the first protection circuit includes a discharge protection circuit, a zero-delay protection circuit, a delay protection circuit, a latch unit, and a third logic gate circuit;

The first input end of the discharge protection circuit is connected to the second end of the latch circuit, and the output end of the discharge protection circuit is respectively connected to the zero-delay protection circuit, the delay protection circuit, the lock unit, the third logic gate circuit, the output terminal of the latch circuit is also connected with the zero delay protection circuit, the delay protection circuit, the zero delay protection circuit and the delay protection circuit The circuit is also connected to the latch unit, the latch unit is connected to the third logic gate circuit, and the third logic gate circuit is connected to the first logic control circuit;

When the latch circuit outputs a protection trigger signal, the discharge protection circuit outputs a first protection signal, the zero-delay protection circuit is triggered to work, the delay protection circuit does not work, and the latch unit passes The zero-delay protection circuit enters a locked state, and in the locked state, the latch unit continues to output the delayed arrival signal, and the third logic gate circuit outputs the delayed arrival signal according to the delayed arrival signal and the first protection signal discharge protection signal.

In a possible design of the first aspect, the power detection circuit includes a charging circuit and a threshold detection unit;

The first terminal of the charging circuit is connected to the power supply terminal, the second terminal of the charging circuit is connected to the ground terminal of the power supply, and the third terminal of the charging circuit is connected to the input terminal of the threshold detection unit , the output end of the threshold detection unit is respectively connected to the first input end of the first protection circuit and the first input end of the first logic control circuit;

The threshold detection unit outputs a first-level signal when its input voltage satisfies the first condition, and the output signal changes from the first-level signal to a second-level signal when its input voltage satisfies the second condition, so The second signal is the second level signal or an edge signal from the first level signal to the second level signal.

As an example, the charging circuit includes a first charging element and a first capacitor;

The first end of the first charging element is connected to the power supply end, the second end of the first charging element is connected to the first end of the first capacitor, and the first charging element and the The connection point of the first capacitor is connected to the input terminal of the threshold detection unit, and the second terminal of the first capacitor is connected to the ground terminal of the power supply;

Wherein, the first charging element is a resistor, a depletion switch, a capacitor or a current source;

The threshold detection unit outputs a first level signal when its input voltage is less than a first voltage threshold, and the output signal changes from the first level signal to a second level signal when its input voltage reaches the first voltage threshold .

As another example, the charging circuit includes a first capacitor and a first charging element;

The first end of the first capacitor is connected to the power supply end, the second end of the first capacitor is connected to the first end of the first charging element, and the first capacitor and the first A connection point of a charging element is connected to the input end of the threshold detection unit, and a second end of the first charging element is connected to the ground end of the power supply;

Wherein, the first charging element is a resistor, a depletion switch, a current source or a capacitor;

The threshold detection unit outputs a first level signal when its input voltage is greater than a first voltage threshold, and the output signal changes from the first level signal to a second level signal when its input voltage drops to less than or equal to the first voltage threshold. two-level signal.

Optionally, the power detection circuit further includes a second switch unit, the first end of the second switch unit is connected to the power supply end, the second end of the second switch unit is connected to the threshold detection unit connected to the input end of the second switch unit, and the control end of the second switch unit is connected to the output end of the threshold detection unit;

When the threshold detection unit outputs a first level signal, the second switch unit is turned off, and when the threshold detection unit outputs a second level signal, the second switch unit is turned on.

In a possible design of the first aspect, when power is turned on, the time required for the first protection circuit to control the first switch circuit to be turned on is longer than the time required for the power detection circuit to control the first switch circuit to be turned off. required time.

In yet another possible design of the first aspect, circuits other than the first switch circuit of the battery protection circuit are located on the same chip, the first switch circuit is located on another chip, and the power supply terminal is a power supply pin, the power ground terminal is a power ground pin, and the system terminal is a system pin; or,

The battery protection circuit is located on the same chip, the power supply terminal is a power supply pin, the power ground terminal is a power ground pin, and the system terminal is a system pin.

In a second aspect, an embodiment of the present application provides an electronic device, including:

Battery;

charging device and/or load;

According to the first aspect and each possible design of the battery protection circuit;

The power supply end and the power ground end of the battery protection circuit are correspondingly connected to the positive pole and the negative pole of the battery, the system end of the battery protection circuit is connected to the charging device and/or the load, and the charging device and/or the The load is also used to connect to the positive or negative pole of the battery.

The battery protection circuit and electronic equipment provided by the present application, wherein the battery protection circuit includes a power detection circuit, a first protection circuit, a first logic control circuit and a first switch circuit, the first input terminal of the first logic control circuit, the second The input ends are respectively connected to the power detection circuit and the first protection circuit, and the output end of the first logic control circuit is connected to the first switch circuit. In this way, the first logic control circuit can be controlled when the power detection circuit outputs the first level signal. The first switch circuit is turned off, and when the power detection circuit outputs the second signal, the first protection circuit outputs the discharge protection signal, triggering the battery protection circuit to enter the discharge protection state, and when the battery protection circuit is in the discharge protection state, the first logic control The circuit can control the first switch circuit to keep off, so that when the power detection circuit detects the power signal, the battery protection circuit automatically enters and locks in the cut-off state, avoiding the battery protection circuit connected with the load circuit and the battery assembly process. There may be equipment failure problems caused by unstable voltage power-on.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description serve to explain the principles of the application.

FIG. 1A is a schematic diagram of a circuit module of an electronic device provided in the first embodiment of the present application;

FIG. 1B is a schematic diagram of another circuit module of the electronic device provided in the first embodiment of the present application;

FIG. 2 is a schematic diagram of a circuit structure of an electronic device provided in a second embodiment of the present application;

FIG. 3A is a schematic diagram of a circuit structure of an electronic device provided in a third embodiment of the present application;

FIG. 3A1 is a schematic diagram of a circuit structure of the over-discharge voltage protection circuit in FIG. 3A;

FIG. 3A2 is a schematic diagram of another circuit structure of the over-discharge voltage protection circuit in FIG. 3A;

FIG. 3B is a schematic diagram of another circuit structure of the electronic device provided in the third embodiment of the present application;

FIG. 3B1 is a schematic diagram of a circuit structure of the discharge overcurrent protection circuit in FIG. 3B;

FIG. 3B2 is a schematic diagram of another circuit structure of the discharge overcurrent protection circuit in FIG. 3B;

FIG. 3C is a schematic diagram of another circuit structure of the electronic device provided in the third embodiment of the present application;

FIG. 4A is a schematic diagram of a circuit structure of an electronic device provided in a fourth embodiment of the present application;

FIG. 4B is a schematic diagram of the circuit structure of another electronic device provided in the fourth embodiment of the present application;

FIG. 4C is a schematic circuit diagram of another electronic device provided in the fourth embodiment of the present application;

FIG. 4D is a schematic circuit diagram of another electronic device provided in the fourth embodiment of the present application;

FIG. 5A is a schematic diagram of a circuit structure of an electronic device provided in a fifth embodiment of the present application;

FIG. 5B is a schematic diagram of another circuit structure of the electronic device provided by the fifth embodiment of the present application;

FIG. 5C is a schematic diagram of another circuit structure of the electronic device provided in the fifth embodiment of the present application;

FIG. 5D is a schematic diagram of changes in the input voltage and output voltage of the threshold detection unit;

FIG. 6 is a schematic diagram of the internal structure of the battery protection circuit provided by the embodiment of the present application;

FIG. 7 is a schematic diagram of a circuit structure of an electronic device provided by a sixth embodiment of the present application.

By means of the above drawings, specific embodiments of the present application have been shown, which will be described in more detail hereinafter. These drawings and text descriptions are not intended to limit the scope of the concept of the application in any way, but to illustrate the concept of the application for those skilled in the art by referring to specific embodiments.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

The terms "comprising" and "having" and any variations thereof appearing in the specification, claims and drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or modules is not limited to the listed steps or units, but optionally also includes unlisted steps or units, or optionally further includes For other steps or units inherent in these processes, methods, products or apparatuses.

In addition, the terms "first", "second", and "third", etc. are used to distinguish different objects, and are not used to describe a specific order. The electrical connection in this application includes direct electrical connection and indirect electrical connection. The indirect electrical connection means that there may be other electronic components, pins, etc. between two electrically connected components. The XX terminal mentioned in this application may or may not be an actual terminal, for example, it is only one end of a component or one end of a wire. The "and/or" mentioned in this application includes three situations, for example, A and/or B includes the three situations of A, B, A and B.

With the popularity of portable electronic products such as mobile phones, tablet computers, mobile power supplies, Bluetooth headsets, and electronic cigarettes, batteries have been widely used as power supply devices, especially lithium batteries. Due to the active chemical activity of the battery, if abnormal conditions such as overcharge, overdischarge, overcurrent, short circuit, and overtemperature charge and discharge occur during charging and discharging, the battery may explode or be damaged. In order to avoid the occurrence of the above-mentioned abnormal situation, the battery is equipped with a battery protection circuit to protect it in practical applications, so as to ensure the safety of the battery.

In practical applications, after the battery protection circuit, the load circuit, and the battery (ie, battery cells) are assembled, the battery can supply power to the load circuit through the battery protection circuit. However, during the assembly process of the battery and the battery protection circuit, there may be a problem of frequent power-on and power-off of the battery protection circuit and/or load circuit due to unstable battery voltage, which may lead to equipment failure in severe cases.

To solve this problem, the inventor of the present application has developed a battery protection circuit through research on the battery protection circuit. This battery protection circuit can automatically enter and maintain the discharge protection state during the first power-on process without the need for external The triggering of the device reduces the cost, and can avoid the problem of device failure caused by the unstable battery voltage that may occur during the battery protection circuit and battery assembly process.

Exemplarily, the battery protection circuit provided by the embodiment of the present application may include a power detection circuit, a first protection circuit, a first logic control circuit and a first switch circuit, the first input terminal and the second input terminal of the first logic control circuit Correspondingly connected to the power detection circuit and the first protection circuit, the output end of the first logic control circuit is connected to the first switch circuit, so that the first logic control circuit can control the first level signal when the power detection circuit outputs the first level signal The switch circuit is turned off, and when the power detection circuit outputs the second signal, the first protection circuit outputs the discharge protection signal, triggering the battery protection circuit to enter the discharge protection state, and when the battery protection circuit is in the discharge protection state, the first logic control circuit can Control the first switch circuit to keep off.

In the embodiment of the present application, when the power detection circuit detects the power signal (power-on), the battery protection circuit automatically turns off the first switch circuit and keeps it in the off state, avoiding the connection between the battery protection circuit and the load circuit, battery The problem of equipment failure that may occur during the assembly process. In addition, this solution does not require the introduction of additional equipment, and the cost is low.

The technical solution of the present application and how the technical solution of the present application solves the above technical problems will be described in detail below with specific embodiments. The following specific embodiments may be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. Embodiments of the present application will be described below in conjunction with the accompanying drawings.

Exemplarily, FIG. 1A is a schematic diagram of a circuit module of an electronic device provided in the first embodiment of the present application. FIG. 1B is a schematic diagram of another circuit module of the electronic device provided in the first embodiment of the present application. As shown in FIG. 1A and FIG. 1B , the electronic device may include a battery 10 , a battery protection circuit 20 and a load circuit 30 . Wherein, the battery protection circuit 20 may include a power detection circuit 201 , a first protection circuit 202 , a first logic control circuit 203 and a first switch circuit 204 . Moreover, the battery protection circuit 20 may include a power supply terminal VDD, a power ground terminal GND and a system terminal VM.

Continue referring to FIG. 1A and FIG. 1B , in the embodiment of the present application, the power supply terminal VDD is connected to the first terminal of the power detection circuit 201, and the second terminal of the power detection circuit 201 is connected to the power ground terminal GND, The output end of the power detection circuit 201 is respectively connected with the first input end of the first protection circuit 202 and the first input end of the first logic control circuit 203, and the output end of the first protection circuit 202 is connected with the first input end of the first logic control circuit 203. The two input terminals are connected, and the output terminal of the first logic control circuit 203 is connected with the control terminal of the first switch circuit 204 .

In the schematic diagram shown in FIG. 1A , the first terminal of the first switch circuit 204 is connected to the power ground terminal GND, and the second terminal of the first switch circuit 204 is connected to the system terminal VM.

In the schematic diagram shown in FIG. 1B , the first terminal of the first switch circuit 204 is connected to the power supply terminal VDD, and the second terminal of the first switch circuit 204 is connected to the system terminal VM.

In the embodiment of the present application, the first logic control circuit 203 is used to control the first switch circuit 204 to turn off when the power detection circuit 201 outputs the first level signal, and when the power detection circuit 201 outputs the second signal, the first The protection circuit 202 outputs a discharge protection signal, and the battery protection circuit 20 enters the discharge protection state. When the battery protection circuit 20 is in the discharge protection state, the first logic control circuit 203 controls the first switch circuit 204 to keep off.

Exemplarily, in this embodiment, the first terminal of the power detection circuit 201 is connected to the power supply terminal VDD, and the power supply terminal VDD is directly or indirectly connected to the positive pole of the battery 10, so that the battery protection circuit 20 can pass the battery detection The circuit 201 detects whether a battery is connected, that is, whether the battery protection circuit 20 is powered on.

Optionally, within the first duration when the battery protection circuit 20 is powered on, the power detection circuit 201 detects a power signal and outputs a first level signal, and when the first logic control circuit 203 receives the first level signal The first switch circuit 204 is controlled to be turned off, so as to cut off the discharge path of the battery 10 .

After the battery protection circuit 20 is powered on for the first time, the power detection circuit 201 outputs a second signal, and the first protection circuit 202 outputs a discharge protection signal, so that the battery protection circuit 20 enters the discharge protection state, and the battery protection circuit 20 is in the discharge protection state. state, the first logic control circuit 203 can control the first switch circuit 204 to keep off, that is, keep the battery protection circuit 20 in the discharge protection state. Wherein, in this embodiment, the second signal is a second-level signal or an edge signal that changes from a first-level signal to a second-level signal.

The embodiment of the present application is mainly applied in the discharge process of the battery 10 to solve the problem that when the battery protection circuit 20 is powered on, the battery 10 may frequently power on and off the battery protection circuit and the load circuit, resulting in damage to electronic equipment. Therefore, the first protection circuit 202 in the embodiment of the present application may be a discharge protection circuit, for example, an over-discharge voltage protection circuit, a discharge over-current protection circuit, and the like. In this way, when the battery protection circuit 20 is powered on and the power detection circuit 201 outputs the second signal, the first protection circuit 202 outputs a discharge protection signal, which can trigger the battery protection circuit 20 to enter the discharge protection state, so that the first logic control circuit 203 controls The first switch circuit 204 remains turned off, and the battery protection circuit 20 remains in a discharge protection state. At this time, the battery 10 cannot be discharged through the battery protection circuit 20 .

In a possible design of the present application, the first switch circuit 204 may include a switch tube and a substrate control circuit, and the switch tube may be a metal-oxide-semiconductor field-effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET, Metal Oxide Half Field Effect Transistor or MOS Transistor for short), the control terminal of the switch tube and the substrate control circuit are both electrically connected to the first logic control circuit 203, and the substrate control circuit is used to realize the correct bias of the substrate of the switch tube. In another possible design of the present application, the first switch circuit 204 may include a charge switch and a discharge switch, wherein the charge switch and the discharge switch may both be MOS transistors, and the charge switch and the discharge switch are respectively connected to the first logic control circuit 203 When the battery protection circuit 20 is powered on, the discharge switch can be controlled to be turned off, and the battery 10 cannot be discharged through the discharge switch at this time.

It can be understood that, in other possible designs of the present application, the first switch circuit 204 may also be implemented in other design forms, for example, only including one switch transistor. The embodiment of the present application does not limit the specific design of the first switch circuit 204 , which can be set according to actual needs, and details are not described here.

In the embodiment of the present application, in the first stage when the battery protection circuit is powered on, the power detection circuit can output a first level signal, so that the first logic control circuit controls the first switch circuit to turn off, and when the battery protection circuit is powered on In the second stage of power-on, the power detection circuit outputs the second signal, which can trigger the first protection circuit to output the discharge protection signal, and the battery protection circuit enters the discharge protection state. At this time, the first logic control circuit can control the first switch circuit to maintain Turn off the cut-off state, so that the battery protection circuit enters and locks in the discharge protection state when it is powered on for the first time, and the battery will not be discharged through the battery protection circuit, thus avoiding the battery voltage instability during the battery protection circuit and battery assembly process. The resulting battery protection circuit and/or load circuit is frequently powered on and powered off, while reducing the power consumption of the battery in the device.

Exemplarily, on the basis of the foregoing embodiments, FIG. 2 is a schematic diagram of a circuit structure of an electronic device provided in a second embodiment of the present application. As shown in FIG. 2 , in this embodiment, the battery protection circuit 20 further includes a latch circuit 205 . The first end of the latch circuit 205 is connected to the output end of the power detection circuit 201 , and the second end of the latch circuit 205 is connected to the first protection circuit 202 .

In this embodiment, the latch circuit 205 enters the locked state when the power detection circuit 201 outputs the second signal, and the latch circuit 205 keeps outputting a protection trigger signal in the locked state, and the protection trigger signal is used to make the first protection circuit 202 outputs a discharge protection signal.

Optionally, as shown in FIG. 2, the latch circuit 205 may be triggered to latch when receiving a first edge signal, and the first edge signal may be an edge from a first level signal to a second level signal signal, therefore, when the power detection circuit 201 outputs the second signal, that is, when the power detection circuit 201 outputs the edge signal or the second level signal from the first level signal to the second level signal, the latch circuit 205 can It enters into a locked state, and can keep outputting a protection trigger signal in the locked state, so that the first protection circuit 202 outputs a discharge protection signal.

Exemplarily, the first level signal is a high level signal, the second level signal is a low level signal, and the first edge signal is a falling edge signal. Therefore, the latch circuit 205 can be activated when receiving the falling edge signal. Trigger latching, that is, lock and save the received low-level signal and output a protection trigger signal, so that the first protection circuit 202 outputs a discharge protection signal, so that the first logic control circuit 203 controls the first protection circuit 203 when receiving the discharge protection signal. The switch circuit 204 is turned off. Exemplarily, the second signal is an edge signal that changes from the first level signal to the second level signal, combined with the latch circuit 205, such setting can make the battery protection circuit 20 complete power-on and the battery protection circuit 20 is in the In the normal working state, even if the power supply detection circuit 201 continues to output the second level signal, the battery protection circuit 20 will not enter the discharge protection state because of the second level signal, that is, it is generally one time to enter the discharge protection state due to power-on triggering. Specifically, the power detection circuit 201 will not trigger the battery protection circuit 20 to enter the discharge protection state at other times when it is powered on.

Optionally, in this embodiment, the latch circuit 205 may be implemented by a D flip-flop, for example, enters into a locked state when receiving a falling edge signal.

In the embodiment of the present application, using the latch circuit 205 to keep outputting the protection trigger signal in the locked state, the input voltage of the first protection circuit 202 can be pulled down or at least some circuit units of the first protection circuit 202 can be activated It is possible to realize that the battery protection circuit 20 enters the discharge protection state, so that the first logic control circuit 203 can keep controlling the first switch circuit 204 to turn off.

Optionally, in practical applications, after the user gets the electronic device including the battery protection circuit, if the electronic device needs to be used normally, the battery protection circuit needs to exit the discharge protection state. However, after the battery protection circuit 20 is powered on, the power detection circuit 201 will always output the second signal, which will cause the first protection circuit 202 to keep outputting the discharge protection signal, or, under the action of the latch circuit 205 to keep outputting the protection trigger signal , the first protection circuit 202 will also keep outputting the discharge protection signal, which may cause the battery protection circuit 20 to fail to exit the discharge protection state, resulting in the failure of the battery to discharge normally. In order to solve this problem, on the basis of the above-mentioned embodiments, the battery protection circuit 20 provided in the above-mentioned embodiments will be improved according to the type of the first protection circuit 202 .

As an example, FIG. 3A is a schematic structural diagram of an electronic device provided in a third embodiment of the present application. In this embodiment, the first protection circuit 202 includes an over-discharge voltage protection circuit 202A. Correspondingly, as shown in FIG. The third switch circuit 206 and the second logic control circuit 207 . The control end of the third switch circuit 206 and the first input end of the second logic control circuit 207 are all connected to the over-discharge voltage protection circuit 202A, and the first end of the third switch circuit 206 and the second input end of the second logic control circuit 207 The input terminals are all connected to the system terminal VM, and the output terminals of the second logic control circuit 207 are respectively connected to the over-discharge voltage protection circuit 202A and the latch circuit 205 .

As an example, when the first terminal of the first switch circuit 204 is connected to the power ground terminal GND, the second terminal of the third switch circuit 206 is connected to the power supply terminal VDD, as shown in FIG. 3A . As another example, when the first terminal of the first switch circuit 204 is connected to the power supply terminal VDD, the second terminal of the third switch circuit 206 is connected to the power supply ground terminal GND.

In this embodiment, when the over-discharge voltage protection circuit 202A outputs the discharge protection signal, the third switch circuit 206 is turned on, the second logic control circuit 207 outputs the first sleep signal, and the over-discharge voltage protection circuit 202A receives the first The discharge protection signal is continuously output during the dormancy signal, and the latch circuit 205 releases the locked state when receiving the first dormancy signal.

Continuing to refer to FIG. 3A , in this embodiment, the over-discharge voltage protection circuit 202A mainly prevents the battery from over-discharging by detecting the battery voltage and the over-discharge detection voltage. For example, in the embodiment shown in FIG. 3A, when the first terminal of the first switch circuit 204 is connected to the power ground terminal GND, the second terminal of the third switch circuit 206 is connected to the power supply terminal VDD, so that when the over-discharge When the voltage protection circuit 202A outputs the discharge protection signal, the third switch circuit 206 is turned on, and the voltage of the system terminal VM is pulled up to the voltage close to the power supply terminal VDD, so that the battery protection circuit 20 remains in the over-discharge voltage protection state.

Exemplarily, assuming that the discharge protection signal is a low-level signal, the third switch circuit 206 includes a third switch unit M3 and a third resistor R3, the third switch unit M3 is a P-type MOS transistor, and the source terminal of the third switch unit M3 It is connected to the power supply terminal VDD, and the drain of the third switch unit M3 is connected to the system terminal VM through the third resistor R3.

In this embodiment, when the battery protection circuit 20 remains in the over-discharge voltage protection state, the voltage of the system terminal VM is a high-level signal. For example, the second logic control circuit 207 may include a NOT gate and a NOR gate, wherein the NOT The input terminal of the gate is connected with the system terminal VM, the output terminal of the NOT gate is connected with the second input terminal of the NOR gate, the first input terminal of the NOR gate is connected with the output terminal of the over-discharge voltage protection circuit 202A, and the output terminal of the NOR gate The output terminals are respectively connected to the latch unit 205 and the over-discharge voltage protection circuit 202A. At this time, the second logic control circuit 207 can output the first sleep signal according to the low-level discharge protection signal and the high-level system terminal voltage signal, For example, the first sleep signal is a high level signal.

In this embodiment, the first sleep signal can enable the over-discharge voltage protection circuit 202A to be continuously enabled or its input voltage to be continuously pulled down, triggering the over-discharge voltage protection circuit 202A to continuously output the discharge protection signal (at this time, actually over-discharge voltage protection signal).

In this embodiment, the first dormancy signal may act on the enable terminal (or reset terminal) of the latch circuit 205, so that the latch circuit 205 releases the locked state when receiving the first dormancy signal. In this way, if the voltage of the system terminal VM changes, the second logic control circuit 207 stops outputting the first sleep signal, so that the over-discharge voltage protection circuit 202A exits the over-discharge voltage protection state, so that the battery protection circuit 20 enters a normal working state.

It can be understood that the change of the voltage of the system terminal VM can be realized in different ways, for example, when the battery protection circuit 20 is connected to the charging device to be charged, the voltage of the system terminal VM will change from a high-level signal to a low-level signal, so that The second logic control circuit 207 stops outputting the first dormancy signal; in addition, the system terminal VM and the power ground terminal GND can be formed into a loop in other ways to pull down the voltage of the system terminal VM. The embodiment of the present application does not limit the way of triggering the change of the VM voltage at the system terminal, which can be set according to actual needs, and details are not described here.

Optionally, based on the embodiment shown in FIG. 3A , FIG. 3A1 is a schematic circuit structure diagram of the over-discharge voltage protection circuit in FIG. 3A . As shown in FIG. 3A1 , the over-discharge voltage protection circuit 202A includes an over-discharge voltage protection unit 202A1 , a delay protection circuit 202A2 , a latch unit 202A3 and a logic gate circuit 202A4 .

In this embodiment, as shown in FIG. 3A1, the output end of the latch circuit 205 is connected to the first input end of the logic gate circuit 202A4, and the output end of the over-discharge voltage protection unit 202A1 is respectively connected to the delay protection circuit 202A2, the latch The unit 202A3 is connected to the second input end of the logic gate circuit 202A4, the delay protection circuit 202A2 is connected to the third input end of the logic gate circuit 202A4 through the latch unit 202A3, and the output ends of the logic gate circuit 202A4 are connected to the second logic control circuit respectively. The first input end of 207, the control end of the third switch circuit 206, and the second input end of the first logic control circuit 203 are connected, and the output end of the second logic control circuit 207 is connected with the latch circuit 205 and the over-discharge voltage protection unit respectively. 202A1 is connected to the delay protection circuit 202A2; wherein, when the logic gate circuit 202A4 receives the protection trigger signal, the logic gate circuit 202A4 outputs the discharge protection signal, the third switch circuit 206 is turned on, and the first logic control circuit 203 controls the first The switch circuit 204 remains turned off, the voltage of the system terminal VM is pulled high, and the second logic control circuit 207 outputs a first dormancy signal according to the discharge protection signal and the voltage signal of the system terminal VM, and the first dormancy signal is used to enable over-discharge The discharge overvoltage protection function of the voltage protection unit 202A1 , the delay function of the shielding delay protection circuit 202A2 and the unlocking state of the latch circuit 205 are released.

In the over-discharge voltage protection circuit 202A of the embodiment of the present application, the logic gate circuit 202A4 is directly connected to the latch circuit 205. Therefore, when the latch circuit 205 outputs a protection trigger signal, the logic gate circuit 202A4 will directly output the discharge protection signal. Make the third switch circuit 206 turn on and conduct, the first logic control circuit 203 controls the first switch circuit 204 to keep off, correspondingly, the voltage of the system terminal VM is pulled up, the second logic control circuit 207 according to the discharge protection signal and the system The voltage signal at the terminal VM will output the first sleep signal to the latch circuit 205, the over-discharge voltage protection unit 202A1 and the delay protection circuit 202A2, so that the discharge over-voltage protection function of the over-discharge voltage protection unit 202A1 is enabled and the delay protection The delay function of the circuit 202A2 is masked and the latch state of the latch circuit 205 is released. Correspondingly, the locked state of the latch circuit 205 is released, and the output of the protection trigger signal is stopped, but the over-discharge voltage protection unit 202A1 outputs the first protection signal, and the first protection signal is directly transmitted without delay processing by the delay protection circuit 202A2 to the latch unit 202A3, so that the latch unit 202A3 continues to output the delayed arrival signal, and the logic gate circuit 202A4 keeps outputting the discharge protection signal according to the first protection signal and the delayed arrival signal.

In this solution, when the over-discharge voltage protection circuit outputs the discharge protection signal, by means of the third switch unit and the second logic control circuit, the locked state of the latch circuit can be released, and the over-discharge voltage protection circuit can also keep the output discharge The protection signal lays the foundation for the subsequent power-on stage to enter the normal working state.

Optionally, on the basis of the embodiment shown in FIG. 3A , FIG. 3A2 is a schematic diagram of another circuit structure of the over-discharge voltage protection circuit in FIG. 3A . 3A2 is similar to FIG. 3A1 , the over-discharge voltage protection circuit 202A includes an over-discharge voltage protection unit 202A1 , a delay protection circuit 202A2 , a latch unit 202A3 and a logic gate circuit 202A4 .

In this embodiment, as shown in FIG. 3A2, the output terminals of the latch circuit 205 are respectively connected to the over-discharge voltage protection unit 202A1 and the delay protection circuit 202A2, and the output terminals of the over-discharge voltage protection unit 202A1 are respectively connected to the delay protection circuit. 202A2, the latch unit 202A3 are connected to the first input terminal of the logic gate circuit 202A4, the delay protection circuit 202A2 is connected to the second input terminal of the logic gate circuit 202A4 through the latch unit 202A3, and the output terminals of the logic gate circuit 202A4 are connected to the second input terminal of the logic gate circuit 202A4 respectively. The first input end of the second logic control circuit 207, the control end of the third switch circuit 206, and the second input end of the first logic control circuit 203 are connected, and the output end of the second logic control circuit 207 is respectively connected with the latch circuit 205, the overpass The discharge voltage protection unit 202A1 is connected; wherein, when the over-discharge voltage protection unit 202A1 receives the protection trigger signal, the over-discharge voltage protection unit 202A1 outputs the first protection signal, and the delay function of the delay protection circuit 202A2 is shielded, and the latch unit 202A3 enters the locked state through the delay protection circuit 202A2. In the locked state, the latch unit 202A3 continues to output the delayed arrival signal, and the logic gate circuit 202A4 outputs the discharge protection signal according to the first protection signal and the delayed arrival signal. The third switch circuit 206 is turned on, the first logic control circuit 203 controls the first switch circuit 204 to keep off, the voltage of the system terminal VM is pulled up, and the second logic control circuit 207 outputs the first Sleep signal, the first sleep signal is used to enable the over-discharge and over-voltage protection function of the over-discharge voltage protection unit 202A1 and release the lock state of the latch circuit 205 .

In the over-discharge voltage protection circuit 202A of the embodiment of the present application, when the latch circuit 205 outputs a protection trigger signal, the input voltage of the over-discharge voltage protection unit 202A1 is pulled down, so that the over-discharge voltage protection unit 202A1 outputs a first protection signal, Since the delay function of the delay protection circuit 202A2 is shielded, the latch unit 202A3 can directly output the delayed arrival signal after latching, and when the over-discharge voltage protection unit 202A1 keeps outputting the first protection signal, the latch unit 202A3 will The delayed arrival signal is continuously output without delay processing by the delay protection circuit 202A2. The logic gate circuit 202A4 outputs the discharge protection signal, so that the third switch circuit 206 is turned on and the first logic control circuit 203 controls the first switch. The circuit 204 remains turned off, the voltage of the system terminal VM is pulled high, and the second logic control circuit 207 outputs the first sleep signal to the latch circuit 205 and the over-discharge voltage protection unit 202A1, so that the over-discharge voltage of the over-discharge voltage protection unit 202A1 The protection function is enabled, and the first protection signal continues to be output, and at the same time, the lock state of the latch circuit 205 is released.

In this embodiment, when the latch circuit outputs the protection trigger signal, the input voltage of the over-discharge voltage protection unit is pulled down, so that the over-discharge voltage protection circuit enters the over-discharge voltage protection state, and then, the second logic control circuit is used to output The first sleep signal of the over-discharge voltage protection unit can be enabled, the over-discharge voltage protection circuit enters the over-discharge voltage protection state, and the lock state of the latch circuit can be released, which lays the foundation for the subsequent battery protection circuit to return to normal working state. Base.

It is worth noting that, optionally, in the above-mentioned embodiments shown in FIG. 3A1 and FIG. 3A2 , the output terminal of the second logic control circuit 207 can also be connected to the logic gate circuit 202A4, so that the output terminal of the over-discharge voltage protection circuit 202A Before the discharge protection signal but the voltage of the system terminal VM is not pulled high, the second logic control circuit 207 can output the second dormancy signal to the logic gate circuit 202A4, so that the logic gate circuit 202A4 directly outputs the discharge protection signal, so that the over-discharge voltage protection circuit The 202A can maintain the over-discharge voltage protection state, which shortens the control path and control time, and further ensures the circuit stability of the battery protection circuit 20 when it is powered on.

It can be understood that in the battery protection circuit 20, when the output terminal or input terminal of the circuit and/or unit is respectively connected to two or more terminals, the output terminal may be the same output terminal, or may be For different output terminals, the input terminals may be the same input terminal or different input terminals, and one or more terminals may be set according to actual needs, which are not limited in this embodiment.

As an example, FIG. 3B is a schematic diagram of another circuit structure of the electronic device provided in the third embodiment of the present application. In this embodiment, the first protection circuit 202 includes a discharge overcurrent protection circuit 202B. Correspondingly, referring to FIG. 3B , the input terminal of the discharge overcurrent protection circuit 202B is connected to the system terminal VM. Four switch circuits 208 and a voltage detection circuit 209 . The control end of the fourth switch circuit 208 and the first input end of the voltage detection circuit 209 are all connected to the discharge overcurrent protection circuit 202B, and the first end of the fourth switch circuit 208 and the second input end of the voltage detection circuit 209 are all connected to the second input end of the voltage detection circuit 209. The system end VM is connected, and the output end of the voltage detection circuit 209 is respectively connected to the discharge overcurrent protection circuit 202B and the latch circuit 205 .

As an example, when the first terminal of the first switch circuit 204 is connected to the power ground terminal GND, the second terminal of the fourth switch circuit 208 is connected to the power supply ground terminal GND, as shown in FIG. 3B . As another example, when the first terminal of the first switch circuit 204 is connected to the power supply terminal VDD, the second terminal of the fourth switch circuit 208 is connected to the power supply terminal VDD.

In this embodiment, when the discharge overcurrent protection circuit 202B outputs a discharge protection signal, the fourth switch circuit 208 is turned on, and the voltage detection circuit 209 outputs a discharge overcurrent protection signal when the discharge overcurrent protection circuit 202B does not enter the discharge overcurrent protection state. A current holding signal, the discharge overcurrent holding signal is used to make the discharge overcurrent protection circuit 202B continuously output the discharge protection signal, and the voltage detection circuit 209 outputs the discharge overcurrent protection signal when the discharge overcurrent protection circuit 202B enters the discharge overcurrent protection state, The latch circuit 205 releases the latch state when receiving the discharge overcurrent protection signal.

Continuing to refer to FIG. 3B , in this embodiment, the discharge overcurrent protection circuit 202B mainly detects the discharge current (the actual detected voltage representing the discharge current) and the preset discharge current (actually the discharge overcurrent threshold voltage) The size of the battery to avoid excessive discharge current. For example, in the embodiment shown in FIG. 3B, when the first terminal of the first switch circuit 204 is connected to the power ground terminal GND, the second terminal of the fourth switch circuit 208 is connected to the power supply ground terminal GND, and the battery protection circuit 20 A load circuit 30 is connected between P+ and P−. In this way, when the discharge overcurrent protection circuit 202B receives the protection trigger signal output by the latch circuit 205 , it can output the discharge protection signal.

When the discharge overcurrent protection circuit 202B outputs the discharge protection signal, the fourth switch circuit 208 is turned on, the first logic control circuit 203 controls the first switch circuit 204 to keep off, and the battery 10, the load circuit 30, and the fourth switch circuit 208 A path is formed, and the voltage of the system terminal VM is pulled up. When the voltage of the system terminal VM is greater than or equal to the discharge overcurrent threshold voltage, the battery protection circuit 20 enters the discharge overcurrent protection state.

Exemplarily, assuming that the discharge protection signal is a low-level signal, the fourth switch circuit includes a fourth switch unit M4 and a fourth resistor R4, the fourth switch unit M4 is an N-type MOS transistor, and the source terminal of the fourth switch unit M4 is connected to the The power supply ground terminal GND is connected, the drain of the fourth switch unit M4 is connected to the system terminal VM through the fourth resistor R4, and the control terminal of the fourth switch unit M4 is connected to the discharge overcurrent protection circuit 202B.

It can be understood that, in this embodiment, the resistance of the fourth resistor R4 is greater than the resistance of the load circuit 30 . Exemplarily, the resistance value of R4 may be between 10k-100k.

In this embodiment, when the discharge overcurrent protection circuit 202B outputs the discharge protection signal, the fourth switch circuit 208 is turned on, the voltage of the system terminal VM is gradually pulled up, and the voltage detection circuit 209 compares the voltage of the system terminal VM with the discharge overcurrent In the first stage, when the voltage of the system terminal VM is less than or equal to the discharge overcurrent threshold voltage, the voltage detection circuit 209 believes that the discharge overcurrent protection circuit 202B has not really entered the discharge overcurrent state, and then outputs the discharge overcurrent Hold the signal to enable the discharge overcurrent protection function of the discharge overcurrent protection circuit 202B, so that the discharge overcurrent protection circuit 202B keeps outputting the discharge protection signal; in the second stage, the voltage of the system terminal VM is pulled up and kept higher And when it is a high level, the voltage of the system terminal VM is greater than the discharge overcurrent threshold voltage. At this time, the voltage detection circuit 209 thinks that the discharge overcurrent protection circuit 202B has really entered the discharge overcurrent state, and then outputs a discharge overcurrent protection signal to release The latch state of the latch circuit 205 is latched and the latch is cleared.

That is to say, the voltage detection circuit 209 outputs the discharge overcurrent hold signal when the voltage of the system terminal VM is less than or equal to the discharge overcurrent threshold voltage, so as to enable the discharge overcurrent protection function of the discharge overcurrent protection circuit 202B, while at the system terminal When the voltage of VM is greater than the discharge overcurrent threshold voltage, it is considered that the discharge overcurrent protection circuit 202B has really entered the discharge overcurrent protection state. At this time, the discharge overcurrent protection signal will be output to the latch circuit 205 to release the latch circuit 205. locked state.

In this embodiment, the discharge overcurrent protection signal can enable the discharge overcurrent protection circuit 202B, trigger the discharge overcurrent protection circuit 202B to continuously output the discharge protection signal, and the discharge overcurrent protection signal can act on the latch circuit 205 to enable Enable terminal (or reset terminal), so that the latch circuit 205 releases the locked state when receiving the discharge overcurrent protection signal. In this way, if the voltage of the system terminal VM changes, and the voltage of the system terminal VM is less than or equal to the discharge overcurrent threshold voltage, the voltage detection circuit 209 stops outputting the discharge overcurrent protection signal, and the discharge overcurrent protection circuit 202B also quits the battery 10 discharge overcurrent protection, so that the battery protection circuit 20 enters a normal working state.

It can be understood that the change of the voltage of the system terminal VM can be realized in different ways, for example, in the case of discharge overcurrent protection, the first switch circuit 204 remains disconnected, and the fourth resistor between the system terminal VM and the power supply ground GND R4 is connected to the fourth switch unit M4. When the battery protection circuit 20 is connected to the load resistor and the fourth resistor R4 is greater than the load resistor, the voltage of the system terminal VM is at a high level. If the battery protection circuit 20 is disconnected from the load resistor, the voltage of the system terminal VM is pulled to the ground potential, and when the voltage of the system terminal VM drops below the discharge overcurrent threshold voltage, the battery protection circuit 20 exits the discharge overcurrent protection status. The embodiment of the present application does not limit the way of triggering the change of the VM voltage at the system terminal, which can be set according to actual needs, and details are not described here.

Optionally, on the basis of the embodiment shown in FIG. 3B , FIG. 3B1 is a schematic circuit structure diagram of the discharge overcurrent protection circuit in FIG. 3B . As shown in FIG. 3B1 , the discharge overcurrent protection circuit 202B includes a discharge overcurrent protection unit 202B1 , a delay protection circuit 202B2 , a latch unit 202B3 and a logic gate circuit 202B4 .

3B1, the output of the latch circuit 205 is connected to the first input of the logic gate circuit 202B4, and the output of the discharge overcurrent protection unit 202B1 is connected to the delay protection circuit 202B2, the latch unit 202B3 and the logic gate circuit respectively. The second input end of 202B4 is connected, and the delay protection circuit 202B2 is connected with the third input end of the logic gate circuit 202B4 through the latch unit 202B3, and the output end of the logic gate circuit 202B4 is respectively connected with the first input end of the voltage detection circuit 209, The control end of the fourth switch circuit 208 is connected to the second input end of the first logic control circuit 203, and the output end of the voltage detection circuit 209 is respectively connected to the latch circuit 205, the discharge overcurrent protection unit 202B1 and the delay protection circuit 202B2;

The logic gate circuit 202B4 outputs a discharge protection signal when receiving the protection trigger signal, the fourth switch circuit 208 is turned on, the first logic control circuit 203 controls the first switch circuit 204 to keep off, the voltage of the system terminal VM rises, and When the voltage of the system terminal VM is less than or equal to the discharge overcurrent threshold voltage, the discharge overcurrent protection unit 202B1 does not enter the discharge overcurrent protection state, and the voltage detection circuit 209 outputs a discharge overcurrent hold signal, and the voltage of the system terminal VM is greater than the discharge overcurrent protection state. When the threshold voltage is reached, the discharge overcurrent protection unit 202B1 enters the discharge overcurrent protection state, and the voltage detection circuit 209 outputs a discharge overcurrent protection signal, wherein the discharge overcurrent hold signal is used to enable the discharge overcurrent protection of the discharge overcurrent protection unit 202B1 function and shield the delay function of the delay protection circuit 202B2, the latch unit 202B3 enters the lock state through the delay protection circuit 202B2 and continues to output the delay arrival signal in the lock state, the logic gate circuit 202B4 keeps outputting the discharge protection signal, and the discharge is over The flow protection signal is used to unlock the latch circuit 205 and clear the latch.

In the discharge overcurrent protection circuit 202B of the embodiment of the present application, the logic gate circuit 202B4 is directly connected to the latch circuit 205. Therefore, when the latch circuit 205 outputs a protection trigger signal, the logic gate circuit 202B4 will directly output the discharge protection signal. The fourth switch circuit 208 is turned on, and the first logic control circuit 203 controls the first switch circuit 204 to keep off. Correspondingly, since the battery protection circuit 20 is connected to the load circuit 30, the voltage of the system terminal VM is gradually pulled up. , when the voltage of the system terminal VM is less than or equal to the discharge overcurrent threshold voltage, the discharge overcurrent protection unit 202B1 does not actually enter the discharge overcurrent protection state, but the voltage detection circuit 209 will output a discharge overcurrent hold signal to the discharge overcurrent protection unit 202B1 and the delay protection circuit 202B2, so that the discharge overcurrent protection unit 202B1 outputs the first protection signal and shields the delay function of the delay protection circuit 202B2, so that the latch unit 202B3 enters the locked state after passing the delay protection circuit 202B2, and In the locked state, the latch unit 202B3 continues to output the delayed arrival signal, and the logic gate circuit 202B4 outputs the discharge protection signal according to the first protection signal and the delayed arrival signal; when the voltage of the system terminal VM is greater than or equal to the discharge overcurrent threshold voltage, The discharge overcurrent protection unit 202B1 really enters the discharge overcurrent protection state, the discharge overcurrent protection unit 202B1 outputs the first protection signal, and the latch unit 202B3 continues to output the delayed arrival signal until the protection signal output by the discharge overcurrent protection unit 202B1 changes When the latch is cleared, the logic gate circuit 202B4 continues to output the discharge protection signal, and the voltage detection circuit 209 outputs the discharge overcurrent protection signal to the latch circuit 205, and the latch circuit 205 unlocks the locked state when receiving the discharge overcurrent protection signal and Clear the latch.

It can be understood that in this embodiment, the discharge overcurrent protection unit 202B1 can judge whether to enter the discharge overcurrent protection state according to the voltage of the system terminal VM, or enter the discharge overcurrent protection state according to the discharge overcurrent maintenance signal received from the voltage detection circuit 209. current protection state, and the discharge overcurrent holding signal can shield the delay function of the delay protection circuit 202B2, and the two work together to effectively avoid the power-on jitter problem that may occur in the battery protection circuit 20 during power-on.

Optionally, on the basis of the embodiment shown in FIG. 3B , FIG. 3B2 is a schematic diagram of another circuit structure of the discharge overcurrent protection circuit in FIG. 3B . 3B2 is similar to FIG. 3B1 , the discharge overcurrent protection circuit 202B includes a discharge overcurrent protection unit 202B1 , a delay protection circuit 202B2 , a latch unit 202B3 and a logic gate circuit 202B4 .

In this embodiment, as shown in FIG. 3B2, the output terminals of the latch circuit 205 are respectively connected to the discharge overcurrent protection unit 202B1 and the delay protection circuit 202B2, and the output terminals of the discharge overcurrent protection unit 202B1 are respectively connected to the delay protection circuit. 202B2, the latch unit 202B3 are connected to the first input end of the logic gate circuit 202B4, the delay protection circuit 202B2 is connected to the second input end of the logic gate circuit 202B4 through the latch unit 202B3, and the output terminals of the logic gate circuit 202B4 are respectively connected to the voltage The first input terminal of the detection circuit 209, the control terminal of the fourth switch circuit 208 and the second input terminal of the first logic control circuit 203 are connected;

When the discharge overcurrent protection unit 202B1 receives the protection trigger signal, the discharge overcurrent protection unit 202B1 outputs the first protection signal, the delay function of the delay protection circuit 202B2 is shielded, and the latch unit 202B3 enters the lock via the delay protection circuit 202B2 In the locked state, the latch unit 202B3 continues to output the delayed arrival signal until the output signal of the discharge overcurrent protection unit 202B1 changes and the latch is cleared. The logic gate circuit 202B4 outputs the discharge protection signal according to the first protection signal and the delayed arrival signal, the fourth switch circuit 208 is turned on, the first logic control circuit 203 controls the first switch circuit 204 to keep off, and the voltage of the system terminal VM rises. High, when the voltage of the system terminal VM is less than or equal to the discharge overcurrent threshold voltage, the voltage detection circuit 209 outputs a discharge overcurrent hold signal; when the voltage of the system terminal VM is greater than the discharge overcurrent threshold voltage, the voltage detection circuit 209 outputs the discharge overcurrent threshold voltage. current protection signal, wherein the discharge overcurrent hold signal is used to enable the discharge overcurrent protection function of the discharge overcurrent protection unit 202B1, and the discharge overcurrent protection signal is used to release the latch state of the latch circuit 205 and clear the latch.

In the discharge overcurrent protection circuit 202B of the embodiment of the present application, when the latch circuit 205 outputs a protection trigger signal, the discharge overcurrent function of the discharge overcurrent protection unit 202B1 is enabled, so that the discharge overcurrent protection unit 202B1 outputs the first protection signal, because the delay function of the delay protection circuit 202B2 is shielded, the latch unit 202B3 can directly output the delayed arrival signal after latching, and during the period when the discharge overcurrent protection unit 202B1 keeps outputting the first protection signal, the latch unit 202B3 will continue to output the delayed arrival signal, without further delay processing by the delay protection circuit 202B2, the logic gate circuit 202B4 outputs the discharge protection signal, so that the fourth switch circuit 208 is turned on and the first logic control circuit 203 controls the second A switch circuit 204 remains turned off. At this time, when the battery protection circuit 20 is connected to the load circuit 30, the voltage of the system terminal VM will be gradually pulled up. When the voltage of the system terminal VM is less than or equal to the discharge overcurrent threshold voltage, the voltage The detection unit 209 outputs the discharge overcurrent hold signal to the latch circuit 205 and the discharge overcurrent protection unit 202B1, the latch circuit 205 continues to output the protection trigger signal, and the discharge overcurrent protection unit 202B1 plays a role in the protection trigger signal or the discharge overcurrent hold signal is continuously enabled, so that the logic gate circuit 202B4 keeps outputting the discharge protection signal; when the voltage of the system terminal VM is greater than the discharge overcurrent threshold voltage, the voltage detection unit 209 will output the discharge overcurrent protection signal to the latch circuit 205 to unlock storage circuit 205 in the locked state, but the discharge overcurrent protection circuit 202B really enters the discharge overcurrent protection state, the discharge overcurrent protection unit 202B1 keeps outputting the first protection signal, the latch unit 202B3 continues to output the delayed arrival signal, and the logic gate circuit 202B4 It will keep outputting the discharge protection signal.

It is worth noting that, optionally, in the above-mentioned embodiments shown in FIG. 3B1 and FIG. 3B2 , the output terminal of the voltage detection circuit 209 can also be connected to the logic gate circuit 202B4, so that the discharge overcurrent protection circuit 202B outputs discharge protection signal but before the voltage of the system terminal VM is pulled high, the voltage detection circuit 209 can output the discharge overcurrent holding signal to the logic gate circuit 202B4, so that the logic gate circuit 202B4 directly outputs the discharge protection signal, so that the discharge overcurrent protection circuit 202B can maintain In the discharge overcurrent protection state, the control path and control duration are shortened, further ensuring the circuit stability of the battery protection circuit 20 when it is powered on.

Optionally, in another possible design of the present application, FIG. 3C is another schematic circuit structure diagram of the electronic device provided in the third embodiment of the present application. As shown in FIG. 3C, the first protection circuit 202 includes a discharge overcurrent protection unit 202B1, a delay protection circuit 202B2, a latch unit 202B3, a first logic gate circuit 202B4, and a second logic gate circuit 202B5. The battery protection circuit 20 also includes The fourth switch circuit 208 .

Wherein, the output terminal of the latch circuit 205 is connected with the first input terminal of the second logic gate circuit 202B5, and the output terminal of the discharge overcurrent protection unit 202B1 is connected with the delay protection circuit 202B2, the latch unit 202B3 and the first logic gate circuit respectively. The first input end of 202B4 is connected, and the delay protection circuit 202B2 is connected with the second input end of the first logic gate circuit 202B4 through the latch unit 202B3, and the output end of the first logic gate circuit 202B4 is connected with the second logic gate circuit 202B5 respectively. The second input terminal is connected to the latch circuit 205 , and the output terminal of the second logic gate circuit 202B5 is respectively connected to the control terminal of the fourth switch circuit 208 and the second input terminal of the first logic control circuit 203 .

When the first terminal of the first switch circuit 204 is connected to the power ground terminal GND, the second terminal of the fourth switch circuit 208 is connected to the power supply ground terminal GND, or, the first terminal of the first switch circuit 204 is connected to the power supply terminal VDD When the second terminal of the fourth switch circuit 208 is connected to the power supply terminal VDD;

When the second logic gate circuit 202B5 receives the protection trigger signal, the second logic gate circuit 202B5 outputs the discharge protection signal, the fourth switch circuit 208 is turned on, and the first logic control circuit 203 controls the first switch circuit 204 to keep off, The voltage of the system terminal VM increases, so that the discharge overcurrent protection unit 202B1 outputs the first protection signal, and the latch unit 202B3 enters the locked state through the delay protection circuit 202B2, and in the locked state, the latch unit 202B3 continues to output the delayed arrival signal , the latch is cleared until the output signal of the discharge overcurrent protection unit 202B1 changes. The first logic gate circuit 202B4 outputs the discharge overcurrent protection signal according to the first protection signal and the delayed arrival signal, the second logic gate circuit 202B5 continuously outputs the discharge protection signal, and the latch circuit 205 releases the locking state when receiving the discharge overcurrent protection signal .

In this possible design, if the first logic gate circuit 202B4 continues to output the discharge overcurrent protection signal, it can be considered that the first protection circuit enters and remains in the real discharge overcurrent protection state, and the latch circuit 205 can release the latch, so that The battery protection circuit 20 can exit the power-on protection stage and enter the normal working state when the voltage change of the system terminal VM meets the requirements.

In the embodiment of this application, the battery protection circuit can automatically enter the locked state when it is powered on, and exit the locked state when the voltage of the system terminal VM changes to less than or equal to the discharge overcurrent threshold voltage, thereby ensuring that the user can get the assembly Electronic equipment with the battery protection circuit can be used normally, improving user experience.

It can be understood that in the battery protection circuit 20, when the output terminal or input terminal of the circuit and/or unit is respectively connected to two or more terminals, the output terminal may be the same output terminal, or may be For different output terminals, the input terminals may be the same input terminal or different input terminals. One or more terminals may be set according to actual needs, which is not limited in this embodiment. For example, the output end of the discharge overcurrent protection circuit 202B can be the output end of the last stage circuit of the discharge overcurrent protection circuit 202B, and can also be the output end of the intermediate stage circuit of the discharge overcurrent protection circuit 202B. Different output ends are connected The post-stage circuit may be different, and details will not be described here.

Optionally, on the basis of the foregoing embodiments, the first protection circuit 202 may be implemented through different components.

In a possible design of the embodiment of the present application, FIG. 4A is a schematic circuit structure diagram of an electronic device provided in the fourth embodiment of the present application. This embodiment is an explanation of the first protection circuit 202 . As shown in FIG. 4A , in this embodiment, the first protection circuit 202 includes a discharge protection circuit 2021 , a delay protection circuit 2022 and a logic gate circuit 2023 .

Wherein, the first input end of the discharge protection circuit 2021 is connected to the second end of the latch circuit 205, and the output end of the discharge protection circuit 2021 is respectively connected to the first input end of the delay protection circuit 2022 and the logic gate circuit 2023, and the delay The timing protection circuit 2022 is also connected to the second terminal of the latch circuit 205 and the second input terminal of the logic gate circuit 2023 . When the latch circuit 205 outputs the protection trigger signal, the discharge protection circuit 2021 outputs the first protection signal, and the delay function of the delay protection circuit 2022 is shielded, that is, after the delay protection circuit 2022 receives the protection trigger signal, it proceeds After receiving the first protection signal, the delayed arrival signal will be output immediately without delay, and the delayed arrival signal will be maintained. Combined with the first protection signal and the delayed arrival signal, the logic gate circuit 2023 outputs a discharge protection signal.

In this embodiment, the output end of the latch circuit 205 is connected to the discharge protection circuit 2021 and the delay protection circuit 2022 at the same time, and the output end of the discharge protection circuit 2021 is connected to the delay protection circuit 2022 and the logic gate circuit 2023 at the same time, like this, When the latch circuit 205 outputs a protection trigger signal, on the one hand, the protection trigger signal can trigger the discharge protection circuit 2021 to be enabled to enter the discharge protection state or the input voltage of the discharge protection circuit 2021 is pulled down to enter the discharge protection state, so that the discharge The protection circuit 2021 outputs the first protection signal. On the other hand, the protection trigger signal can shield the delay function of the delay protection circuit 2022, so that the first protection signal does not need to be processed by the delay protection circuit 2022. Therefore , the time for the discharge protection signal to be transmitted to the logic gate circuit 2023 is shortened, and the delayed arrival signal output by the delay protection circuit 2022 (a signal that does not need to be delayed) and the first protection signal output by the discharge protection circuit 2021 work together to generate discharge The protection signal further ensures that the logic gate circuit 2023 can output the discharge protection signal in time, so that the first logic control circuit 203 can control the first switch circuit 204 to keep off and off in time. Since no delay is required, the power detection circuit 2021 When switching from outputting the first level signal to outputting the second level signal, there will be no problem that the first switch circuit is turned on.

It can be understood that when the discharge protection circuit 2021 continues to output the first protection signal, the logic gate circuit 2023 continues to output the discharge protection signal until the protection signal of the discharge protection circuit 2021 changes. Wherein, the discharge protection signal may be the output signal of the first protection circuit 202 , which is a signal obtained by logically processing the first protection signal and the delayed arrival signal output by the delay protection circuit 2022 .

In another possible design of the embodiment of the present application, FIG. 4B is a schematic circuit structure diagram of another electronic device provided in the fourth embodiment of the present application. This embodiment is also an explanation of the specific implementation of the first protection circuit 202 . As shown in FIG. 4B , in this embodiment, the first protection circuit 202 includes a discharge protection circuit 2021 , a delay protection circuit 2022 and a logic gate circuit 2024 .

Wherein, the input terminal of the discharge protection circuit 2021 is connected with the power supply terminal VDD or the system terminal VM, and the output terminal of the discharge protection circuit 2021 is respectively connected with the input terminal of the delay protection circuit 2022 and the first input terminal of the logic gate circuit 2024, delay The output terminal of the time protection circuit 2022 is connected with the second input terminal of the logic gate circuit 2024, the third input terminal of the logic gate circuit 2024 is connected with the output terminal of the latch circuit 205, and the output terminal of the logic gate circuit 2024 is connected with the first logic control circuit. The circuit 203 is connected; when the latch circuit 205 outputs the protection trigger signal, the logic gate circuit 2024 outputs the discharge protection signal.

As an example, when the discharge protection circuit 2021 includes an over-discharge voltage protection unit, the input terminal of the discharge protection circuit 2021 is connected to the power supply terminal VDD, and the discharge protection state is the over-discharge voltage protection state. In this embodiment, during the normal discharge process of the battery protection circuit 20, the discharge protection circuit 2021 can judge the size of the battery voltage and the preset over-discharge detection voltage, if the battery voltage drops below the over-discharge detection voltage and the duration reaches the over-discharge If the voltage detection delay time is longer or longer, the over-discharge voltage protection unit will output an over-discharge voltage protection signal, so that the battery protection circuit 20 enters the over-discharge voltage protection state, and the first logic control circuit 203 controls the first switch circuit 204 to keep off. , the battery 10 stops discharging.

As another example, when the discharge protection circuit 2021 includes a discharge overcurrent protection unit, the input end of the discharge protection circuit 2021 is connected to the system terminal VM, and the discharge protection state is the discharge overcurrent protection state. When the battery protection circuit 20 is in a normal working state, the discharge protection circuit 2021 can determine the magnitude of the discharge current and the preset discharge current (actually, the voltage representing the discharge current (the voltage of the system terminal VM) and the discharge overcurrent threshold voltage), if the discharge When the current is equal to or higher than the preset discharge current and the duration reaches the discharge overcurrent detection delay time, the discharge overcurrent protection unit will output the first protection signal, and the logic gate circuit 2024 will output the discharge overcurrent protection signal, which can make the battery protection circuit 20 enter In the discharge overcurrent protection state, the first logic control circuit 204 controls the first switch circuit 204 to keep off, and the battery 10 stops discharging.

Therefore, in the embodiment of the present application, the input terminal of the discharge protection circuit 2021 is connected to the power supply terminal VDD or the system terminal VM. When the battery protection circuit 20 is powered on, under normal circumstances, the discharge protection circuit 2021 will not output First protection signal. However, referring to FIG. 4B , when the power detection circuit 201 outputs a first level signal, the first logic control circuit 203 electrically connected to the power detection circuit 201 will be triggered to control the first switch circuit 204 to turn off. When the power detection circuit 201 outputs the second signal, the latch circuit 205 will enter the lock state and keep outputting the protection trigger signal to the logic gate circuit 2024 in the lock state, so that the logic gate circuit 2024 directly outputs the discharge protection signal, which can also make the second A logic control circuit 203 controls the first switch circuit 204 to turn off when receiving the discharge protection signal. Therefore, when the battery protection circuit 20 is powered on, the battery protection circuit 20 will enter and remain in the discharge protection state to prevent the battery 10 from discharging.

In this possible design, the first protection circuit 202 includes a logic gate circuit 2024, so that when the latch circuit 205 outputs a protection trigger signal, the first protection circuit 202 can directly output the over-discharge protection signal without going through the discharge protection circuit 2021. The determination and the delay processing of the delay protection circuit 2022 lay the foundation for the battery protection circuit 20 to remain in the discharge protection state.

In another possible design of the embodiment of the present application, FIG. 4C is a schematic circuit structure diagram of another electronic device provided in the fourth embodiment of the present application. This embodiment is also an explanation of the specific implementation of the first protection circuit 202 . As shown in FIG. 4C, in this embodiment, the first protection circuit 202 includes a discharge protection circuit 2021, a zero-delay protection circuit 2022A, a first latch unit 2025A, a delay protection circuit 2022B, a second latch unit 2025B, The third logic gate circuit 2026A and the fourth logic gate circuit 2026B.

Wherein, the first input end of the discharge protection circuit 2021 is connected to the second end of the latch circuit 205, and the output end of the discharge protection circuit 2021 is respectively connected to the zero-delay protection circuit 2022A, the delay protection circuit 2022B, and the first latch unit 2025A. , the second latch unit 2025B and the third logic gate circuit 2026A are connected, the output end of the latch circuit 205 is also connected with the zero delay protection circuit 2022A and the delay protection circuit 2022B, and the zero delay protection circuit 2022A is also connected with the first lock The delay protection circuit 2022B is also connected to the second latch unit 2025B, the first latch unit 2025A and the second latch unit 2025B are both connected to the fourth logic gate circuit 2026B, and the fourth logic gate circuit 2026B is connected to the fourth logic gate circuit 2026B. The third logic gate circuit 2026A is connected, and the third logic gate circuit 2026A is connected with the first logic control unit 203 .

In this embodiment, when the latch circuit 205 outputs the protection trigger signal, the discharge protection circuit 2021 outputs the first protection signal, the zero-delay protection circuit 2022A is triggered to work, the delay protection circuit 2022B does not work, and the first latch The unit 2025A enters the locked state without delay. In the locked state, the first latch unit 2025A continues to output the first intermediate signal, and the fourth logic gate circuit 2026B receives the first intermediate signal and continues to output the delayed arrival signal. The timely arrival signal and the first protection signal work together to generate a discharge protection signal, that is, the third logic gate circuit 2026A outputs a discharge protection signal according to the delayed arrival signal and the first protection signal.

Thereafter, when the latch circuit 205 does not output a protection trigger signal (for example, after the latch circuit 205 described above is unlocked), the delay protection circuit 2022B works at this time, and the zero delay protection circuit 2022A does not work. When the discharge protection When the circuit 2021 outputs the first protection signal (for example, caused by the aforementioned first sleep signal and/or discharge overcurrent hold signal), since the first latch unit 2025A has latched and output the first intermediate signal, the fourth logic The gate circuit 2026B continues to output the delayed arrival signal, so that when the discharge protection circuit 2021 outputs the first protection signal, the first protection circuit 202 will immediately output the discharge protection signal.

In addition, in this embodiment, when the battery protection circuit 20 has been powered on and is in a normal working state, the delay protection circuit 2022B works at this time, and the zero delay protection circuit 2022A does not work. When the delay protection circuit 2022B continues to receive After the first protection signal and a delay time, the second latch unit 2025B is triggered to enter the locked state. In the locked state, the second latch unit 2025B continues to output the second intermediate signal, and the fourth logic gate circuit 2026B receives the first The second intermediate signal continuously outputs a delayed arrival signal.

In yet another possible design of the embodiment of the present application, FIG. 4D is a schematic circuit structure diagram of another electronic device provided in the fourth embodiment of the present application. The difference between Fig. 4D and Fig. 4C is that in the first protection circuit 202 shown in Fig. 4C, the zero-delay protection circuit 2022A and the delay protection circuit 2022B are equipped with latch units respectively, while in the first protection circuit 202 shown in Fig. 4D In the circuit 202 , the zero-delay protection circuit 2022A and the delay protection circuit 2022B share the latch unit 2025 .

Specifically, as shown in FIG. 4D, in this embodiment, the first protection circuit 202 includes a discharge protection circuit 2021, a zero-delay protection circuit 2022A, a delay protection circuit 2022B, a latch unit 2025, and a third logic gate circuit 2026A. .

Wherein, the first input terminal of the discharge protection circuit 2021 is connected with the second terminal of the latch circuit 205, and the output terminal of the discharge protection circuit 2021 is connected with the zero delay protection circuit 2022A, the delay protection circuit 2022B, the latch unit 2025, the second terminal respectively. Three logic gate circuits 2026A are connected, and the output end of the latch circuit 205 is also connected with the zero delay protection circuit 2022A and the delay protection circuit 2022B, and the zero delay protection circuit 2022A and the delay protection circuit 2022B are all connected with the latch unit 2025, The latch unit 2025 is connected to the third logic gate circuit 2026A, and the third logic gate circuit 2026A is connected to the first logic control circuit 203 .

In this embodiment, when the latch circuit 205 outputs the protection trigger signal, the discharge protection circuit 2021 outputs the first protection signal, the zero-delay protection circuit 2022A is triggered to work, the delay protection circuit 2022B does not work, and the latch unit 2025 The zero-delay protection circuit 2022A immediately enters the locked state. In the locked state, the latch unit 2025 continues to output the delayed arrival signal, and the third logic gate circuit 2026A outputs the discharge protection signal according to the delayed arrival signal and the first protection signal. The first logic control circuit 203 controls the first switch circuit 204 to keep off.

Similar to the description of FIG. 4C, thereafter, when the latch circuit 205 does not output a protection trigger signal, the zero-delay protection circuit 2022A does not work, and the delay protection circuit 2022B works. When the discharge protection circuit 2021 outputs the first protection signal (such as the previous When the first dormancy signal and/or the discharge over-current hold signal are mentioned), since the latch unit 2025 has latched the output delay arrival signal, when the discharge protection circuit 2021 outputs the first protection signal, the third logic gate The circuit 2026A will immediately output the discharge protection signal.

In addition, in this embodiment, when the battery protection circuit 20 has been powered on and is in a normal working state, the delay protection circuit 2022B works at this time, and the zero delay protection circuit 2022A does not work. When the delay protection circuit 2022B continues to receive After the first protection signal and the delay time, the latch unit 2025 is triggered to enter the locked state, and in the locked state, the latch unit 2025 will continue to output the delayed arrival signal.

In addition, in the situation of FIG. 4C and FIG. 4D, since the first latch unit 2025A/second latch unit 2025B/latching unit 2025 is connected to the output terminal of the discharge protection circuit 2021, the first latch unit 2025A/second latch unit 2025A/second The release of the latch state of the latch unit 2025B/latch unit 2025 is: when the battery protection circuit 20 recovers from the discharge protection state to the normal operating state, the protection signal output by the discharge protection circuit 2021 changes (for example, stop outputting the first A protection signal), the latch state of the first latch unit 2025A/second latch unit 2025B is released, the first intermediate signal/second intermediate signal is cleared, and correspondingly, the latch state of the latch unit 2025 is released , the delayed arrival signal is cleared.

In a possible design of the embodiment of the present application, FIG. 5A is a schematic circuit structure diagram of an electronic device provided in the fifth embodiment of the present application. FIG. 5B is a schematic diagram of another circuit structure of the electronic device provided by the fifth embodiment of the present application. This embodiment mainly explains the structure of the power detection circuit 201 in the battery protection circuit 20 . As shown in FIG. 5A and FIG. 5B , the power detection circuit 201 includes a charging circuit 2011 and a threshold detection unit 2012 . Wherein, the first end of the charging circuit 2011 is connected to the power supply terminal VDD, the second end of the charging circuit 2011 is connected to the power grounding terminal GND, the third end of the charging circuit 2011 is connected to the input end of the threshold detection unit 2012, and the threshold detection unit The output terminal of 2012 is respectively connected with the first input terminal of the first protection circuit 202 and the first input terminal of the first logic control circuit 203 .

In this embodiment, the threshold detection unit 2012 outputs a first level signal when its input voltage meets the first condition, and the output signal changes from the first level signal to the second level signal when its input voltage meets the second condition. Correspondingly, the above-mentioned second signal is a second level signal or an edge signal from a first level signal to a second level signal.

Optionally, in the embodiment of the present application, the threshold detection unit 2012 can detect the magnitude of its input voltage in real time, and determine the output signal according to the magnitude of the input voltage. Exemplarily, when the battery protection circuit 20 is initially powered on, the first circuit 2011 is charged, and in the first stage of the first circuit 2011 being charged, the input voltage of the threshold detection unit 2012 satisfies the first condition. At this time, The threshold detection unit 2012 outputs the first level signal, and as the first circuit 2011 is charged, the input voltage of the threshold detection unit 2012 satisfies the second condition, and the first circuit 2011 enters the second stage of being charged, that is, the threshold detection unit 2012 When the input voltage reaches the first voltage threshold, the signal output by the threshold detection unit 2012 changes from the first level signal to the second level signal.

Optionally, as shown in FIG. 5A and FIG. 5B , the first circuit 2011 may include a first charging element 2011A and a first capacitor C1, wherein the first charging element 2011A may be a resistor, a depletion switch, a current source or capacitance. In practical application, when the positions of the first charging element 2011A and the first capacitor C1 are different, the variation trend of the input voltage of the threshold detection unit 2012 is different, which will be explained below with reference to FIG. 5A and FIG. 5B .

As an example, as shown in FIG. 5A, the first end of the first charging element 2011A is connected to the power supply terminal VDD, the second end of the first charging element 2011A is connected to the first end of the first capacitor C1, and, A connection point between a charging element 2011A and the first capacitor C1 is connected to the input terminal of the threshold detection unit 2012, and the second terminal of the first capacitor C1 is connected to the power ground terminal GND.

In the embodiment of the present application, the first charging element 2011A is connected between the power supply terminal VDD and the first capacitor C1. When the battery protection circuit 20 is powered on, the battery 10 can pass the power supply terminal VDD, the first charging element 2011A charges the first capacitor C1, so that the input voltage of the threshold detection unit 2012 increases. That is, the first charging element 2011A can be turned on when there is a voltage difference across the first charging element 2011A, so that the first capacitor C1 is charged. Therefore, in this example, the threshold detection unit 2012 outputs a first-level signal when its input voltage is less than the first voltage threshold, and the output signal changes from the first-level signal to the second-level signal when its input voltage reaches the first voltage threshold. two-level signal.

As another example, as shown in FIG. 5B , the first end of the first capacitor C1 is connected to the power supply terminal VDD, the second end of the first capacitor C1 is connected to the first end of the first charging element 2011A, and, A connection point between a capacitor C1 and the first charging element 2011A is connected to the input end of the threshold detection unit 2012, and the second end of the first charging element 2011A is connected to the power ground terminal GND.

In the embodiment of the present application, the first charging element 2011A is connected between the first capacitor C1 and the power ground GND. Before the battery protection circuit 20 is powered on, the voltage between the two electrodes of the first capacitor C1 Equally, the voltage drop is 0, and the input voltage of the threshold detection unit 2012 is approximately equal to the voltage of the battery 10. When the battery protection circuit 20 is powered on, the battery 10 gradually charges the first capacitor C1, and the two electrodes on the first capacitor C1 The voltage drop between the slices is getting larger and larger, since the input voltage of the threshold detection unit 2012 is equal to the voltage of the battery 10 minus the voltage drop on the first capacitor C1, the input voltage of the threshold detection unit 2012 gradually decreases. Therefore, the threshold detection unit 2012 outputs the first level signal when its input voltage is greater than the first voltage threshold, and the output signal changes from the first level signal to the second when the input voltage drops to less than or equal to the first voltage threshold. level signal.

Optionally, in the embodiment of the present application, the first voltage threshold is the threshold voltage of the threshold detection unit 2012, which may be a set voltage value, and this embodiment does not limit the specific value of the first voltage threshold . Exemplarily, the first charging element 2011A can be implemented by a resistor, a depletion switch or a current source, and how to connect it is a conventional technique in the art, and details will not be repeated here. It can be understood that the first charging element 2011A can also be implemented by other elements, as long as it satisfies the above-mentioned electrical signal transmission principle, which is not limited in this embodiment.

Optionally, on the basis of the above embodiment shown in FIG. 5A , FIG. 5C is another schematic circuit structure diagram of the electronic device provided in the fifth embodiment of the present application. FIG. 5D is a schematic diagram of changes in the input voltage and output voltage of the threshold detection unit. This embodiment is a further description of the structure of the power detection circuit 201 based on the above embodiment shown in FIG. 5A . In this example, the first charging element 2011A is equivalent to a current source as an example for illustration. As shown in FIG. 5C , the power detection circuit 201 further includes a second switch unit M2, the first terminal of the second switch unit M2 is connected to the power supply terminal VDD, and the second terminal of the second switch unit M2 is connected to the threshold detection unit 2012 The input end of the second switch unit M2 is connected to the output end of the threshold detection unit 2012 .

In the embodiment of the present application, when the threshold detection unit 2012 outputs the first level signal, the second switch unit M2 is turned off, and when the threshold detection unit 2012 outputs the second level signal, the second switch unit M2 is turned on. is turned on, so that the voltage of the input terminal of the threshold detection unit 2012 is pulled up.

For example, please refer to FIG. 5C and FIG. 5D . In the embodiment of the present application, when the first charging element 2011A is used as the current source for illustration, when the battery protection circuit 20 is powered on, the first capacitor C1 gradually being charged, the voltage at the input end of the threshold detection unit 2012 gradually increases, that is, the input voltage of the threshold detection unit 2012 gradually increases, when the input voltage of the threshold detection unit 2012 is less than the first voltage threshold, the threshold detection unit 2012 outputs the first voltage A level signal, the first level signal acts on the control terminal of the second switch unit M2, so that the second switch unit M2 is turned off. As the charging progresses, when the input voltage of the threshold detection unit 2012 rises to the first voltage threshold, the signal output by the threshold detection unit 2012 changes from a first level signal to a second level signal, and the second level signal Acting on the control terminal of the second switch unit M2, so that the second switch unit M2 is turned on, and correspondingly, the input voltage of the threshold detection unit 2012 becomes the voltage of the power supply terminal VDD.

It can be understood that when the first charging element 2011A is a resistor, the variation trend of the input voltage of the threshold detection unit 2012 is different, and the slope of the curve can gradually decrease. The specific variation trend is related to the characteristics of the first charging element 2011A. In this embodiment It is not limited.

Optionally, in this embodiment of the present application, the threshold detection unit 2012 may be an inverter with a threshold, for example, a Schmitt trigger, and the second switch unit M2 may be a P-type MOS transistor. When the threshold detection unit 2012 outputs a second level signal, it can trigger the second switch unit M2 to turn on and conduct, so that the input voltage of the threshold detection unit 2012 suddenly changes to the voltage of the power supply terminal VDD, and remains unchanged. Correspondingly, the threshold The detection unit 2012 keeps outputting the second level signal unchanged.

In practical applications, when the voltage of the battery jumps, it may cause the output voltage of the threshold detection unit 2012 to jump, which may cause the circuit receiving the output signal of the threshold detection unit 2012 to be falsely triggered. For this problem, through A second switch unit M2 is added to keep the input voltage of the threshold detection unit 2012 consistent with the voltage of the power terminal of the threshold detection unit 2012 after the input voltage of the threshold detection unit 2012 satisfies the second condition. The problem that the change may cause the output voltage of the threshold detection unit 2012 to jump, reduces the risk of false triggering.

Optionally, for the case where the battery protection circuit 20 includes a latch circuit 205, by adding a second switch unit M2, the output stability of the latch circuit 205 can be guaranteed when the battery voltage jumps, avoiding the The output voltage jump of 2012 may cause the problem that the latch circuit 205 and/or the first logic control circuit 203 are repeatedly falsely triggered.

It can be understood that, on the basis of the embodiment shown in FIG. 5B , the power detection circuit 201 may also include a second switch unit, and its implementation principle and beneficial effects are similar, that is, when the battery protection circuit 20 is powered on, the threshold detection unit 2012 The input voltage of the threshold value detection unit 2012 gradually decreases from the voltage of the power supply, and when the input voltage of the threshold value detection unit 2012 drops to less than or equal to the first voltage threshold, the signal output by the threshold value detection unit 2012 changes from a first level signal to a second level signal , the second level signal acts on the control terminal of the second switch unit M2, so that the second switch unit M2 is turned on, and correspondingly, the input voltage of the threshold detection unit 2012 becomes the voltage of the power ground terminal GND. It can be understood that the slope of the variation curve of the input voltage of the threshold detection unit 2012 can be constant or variable, which is determined according to the properties of the first charging element 2011A, and will not be repeated here.

Optionally, in the battery protection circuit 20 provided in each embodiment of the present application, when the battery protection circuit 20 is powered on, the time required for the first protection circuit 202 to control the first switch circuit 204 to turn on is longer than the time required for the power detection circuit 201 to control the first switch circuit 204 to turn on. A time required for the switch circuit 204 to be turned off, that is, the second logic control unit 2032 preferentially outputs a low-level signal to the first input terminal of the first logic control unit 2031 to control the first switch circuit 204 to be turned off, and the third The logic control unit 2033 outputs a high-level signal to the first logic control unit 2031 relatively later to control the conduction of the first switch circuit 204 (when the power detection circuit outputs the first level signal).

In this embodiment, when the battery protection circuit is just powered on, the power detection circuit outputs a first level signal. At this time, the first logic control circuit will control the first switch circuit to turn off according to the first level signal. When the protection circuit is in a normal working state, the first logic control circuit will control the first switch circuit to be turned on. In order to ensure that the battery protection circuit remains in the cut-off state after being powered on, at this time, the first protection circuit controls the first switch circuit to be turned on The required time needs to be longer than the time required for the power detection circuit to control the first switch circuit to be turned off, so that the first switch circuit can be prevented from being turned on and then turned off, and the stability of the battery protection circuit can be improved.

Optionally, in an embodiment of the present application, the circuits of the battery protection circuit 20 except the first switch circuit 204 are located on the same chip, and the first switch circuit 204 is located on another chip. The power supply terminal VDD is a power supply pin, the power ground terminal GND is a power ground pin, and the system terminal VM is a system pin. In this example, the two chips may or may not be packaged together, which may be determined according to actual requirements, and details will not be described here.

Optionally, in another embodiment of the present application, the battery protection circuit 20 is located on the same chip, the power supply terminal VDD is the power supply pin, the power ground terminal GND is the power ground pin, and the system terminal VM is the system pin.

Optionally, on the basis of the foregoing embodiments of the present application, FIG. 6A is a schematic circuit structure diagram of a battery protection circuit provided in the embodiment of the present application. FIG. 6B is a schematic diagram of another circuit structure of the battery protection circuit provided by the embodiment of the present application. It can be understood that the battery protection circuits shown in FIG. 6A and FIG. 6B may be compatible with the battery protection circuits provided in the above-mentioned embodiments.

As shown in FIG. 6A and FIG. 6B, the battery protection circuit 20 may include a power detection circuit 201, a latch circuit 205, an over-discharge voltage protection unit, an over-charge voltage protection unit, a charging over-current protection unit, a load short-circuit protection unit, a discharge An over-current protection unit, an over-temperature protection (Over Temperature Protection, OTP) unit, a logic control circuit, a first switch circuit 204 and the like.

Wherein, the logic control circuit may include at least one of a delay protection unit, a latch unit, and a logic control unit, each protection unit is connected to the logic control circuit, and when any protection unit outputs a protection signal, the logic control circuit can control the first A switch circuit is turned off and cut off.

In this embodiment, the logic control unit may have all or part of the functions of the first logic control circuit 203, the second logic control circuit 207, or the voltage detection circuit 209 in the above-mentioned embodiments, and may be implemented based on requirements in practical applications. corresponding function. In practical applications, the logic control unit may include one or more logic gates, one or more control components, etc., and the specific components included may be determined based on actual needs. The battery protection circuit 20 may also include other components, which may Corresponding functions are expanded according to actual needs, and details are not described here.

In this embodiment, in the first stage when the battery protection circuit 20 is powered on for the first time, when the power detection circuit 201 outputs a first level signal according to the detected input voltage, the logic control unit of the logic control circuit can control the first switch circuit 204 Turn off and cut off; in the second stage when the battery protection circuit 20 is powered on, when the power detection circuit 201 outputs the second signal according to the detected input voltage, the second signal can also directly act on the logic control circuit, so that the logic control circuit can also directly The first switch circuit 204 is controlled to be turned off, or the second signal can directly act on the latch circuit 205, so that the latch circuit 205 enters a locked state and outputs a protection trigger signal out.

As an example, as shown in FIG. 6A, the output terminal of the locking circuit 205 is connected to the over-discharge voltage protection unit and/or the logic control circuit, and the over-discharge voltage protection unit is connected to the power supply terminal VDD. When the latch circuit 205 outputs When the protection trigger signal is out, the over-discharge voltage protection unit can output the first protection signal. In the logic control circuit, after the first protection signal is processed by the delay protection unit and the latch unit, the latch unit outputs a delayed arrival signal. When the logic control unit determines that the battery protection circuit enters the discharge overvoltage protection state according to the first protection signal and the delayed arrival signal, it controls the first switch circuit 204 to be turned off.

It can be understood that after the battery protection circuit 20 enters the normal working state, the over-discharge voltage protection unit can output the first protection signal (over-discharge voltage protection signal) to the logic control circuit, after being processed by the delay protection unit, the latch unit, and the logic control unit, the logic control circuit can control the first switch circuit 204 to be turned off and cut off, so that the battery stops discharging, thereby realizing the protection of the battery Purpose of over-discharge voltage protection.

As another example, as shown in FIG. 6B, the output terminal of the latch circuit 205 is connected to the discharge overcurrent protection unit and/or the logic control circuit, and the discharge overcurrent protection unit is connected to the system terminal VM. When the latch circuit 205 outputs When the protection trigger signal is out, the discharge overcurrent protection unit can output the first protection signal. In the logic control circuit, after the first protection signal is processed by the delay protection unit and the latch unit, the latch unit outputs a delayed arrival signal. When the logic control unit determines that the battery protection circuit enters the discharge overcurrent protection state according to the first protection signal and the delayed arrival signal, it controls the first switch circuit 204 to be turned off.

It can be understood that after the battery protection circuit 20 enters the normal working state, the discharge overcurrent protection unit can output the first protection signal (discharge overcurrent protection signal) to the logic control circuit when detecting that the discharge current is higher than the preset discharge current, After being processed by the delay protection unit, the latch unit and the logic control unit, the logic control circuit can control the first switch circuit 204 to be turned off, so that the battery stops discharging, and the purpose of discharging overcurrent protection for the battery is achieved.

In addition, continue to refer to FIG. 6A and FIG. 6B, the overcharge voltage protection unit is connected to the power supply terminal VDD, and the overcharge voltage protection unit is used to output when it detects that the battery voltage is too high during charging. The overcharge voltage protection signal is sent to the logic control circuit to turn off the first switch circuit 204, so as to stop charging the battery and achieve the purpose of protecting the battery from overcharge voltage.

The charging overcurrent protection unit is connected to the system terminal VM, and the charging overcurrent protection unit is used to output a charging overcurrent protection signal when the charging current is detected to be too large during the battery charging process, so that the logic control circuit turns off the first switch circuit 204, to stop charging the battery to prevent permanent damage to the battery or safety problems caused by excessive charging current.

The load circuit protection unit is connected to the system terminal VM, and the load circuit protection unit is used to protect the battery when the voltage of the system terminal VM is detected to be higher than the short-circuit protection voltage threshold, for example, the logic control circuit will turn off the first switch circuit 204, to stop the battery from discharging.

In addition, during the charging and discharging process of the battery, the temperature protection unit outputs a temperature protection signal to the logic control circuit when it detects that the temperature of the battery protection circuit 20 exceeds the temperature threshold, so that the logic control circuit controls the first switch circuit 204 to turn off, In this way, the charging of the battery or the discharging of the battery is stopped, so as to prevent permanent damage to the battery or safety problems caused by excessive temperature during the charging and discharging process.

It can be understood that in practical applications, the battery protection circuit 20 may also include other components or circuits, for example, one or more resistors, an oscillator OSC, etc., to improve the safety of the battery during use.

Optionally, the embodiment of the present application further provides an electronic device.

Exemplarily, FIG. 7 is a schematic circuit structure diagram of an electronic device provided in the sixth embodiment of the present application. As shown in Figure 7, the electronic equipment may include:

battery 10;

charging device 30 and/or load 40;

According to the battery protection circuit 20 in the above embodiment shown in FIGS. 1A to 6 .

Wherein, the battery protection circuit 20 may include a power supply terminal VDD, a power ground terminal GND and a system terminal VM, such that the power supply terminal VDD and the power ground terminal GND are connected to the positive pole and the negative pole of the battery 10 correspondingly. The system terminal VM of the battery protection circuit 20 is connected to the charging device 30 and/or the load 40 , and the charging device 30 and/or the load 40 are also used to be connected to the positive pole or the negative pole of the battery 10 . The battery protection circuit 20 can be used to protect the battery 10, prevent the battery 10 from being permanently damaged during charging and discharging, and can also protect the battery protection circuit 20 and the load circuit connected to the battery protection circuit 20 when the battery protection circuit is powered on. Thereby ensuring the use safety of electronic equipment.

In the embodiment of the present application, the electronic device is, for example, a rechargeable electronic device such as a Bluetooth headset, a mobile phone, a tablet computer, and an electronic cigarette.

In a possible design of the present application, the battery 10 can be a rechargeable battery, and the capacity of the rechargeable battery can be 100mAh-2000mAh, for example, 100mAh, 200mAh, 300mAh, 400mAh, 500mAh, 600mAh, 700mAh, 800mAh, 900mAh, 1000mAh, 1100mAh, 1200mAh, 1300mAh, 1400mAh, 1500mAh, 1600mAh, 1700mAh, 1800mAh, 1900mAh, 2000mAh, etc. As an example, rechargeable batteries have a capacity of 300mAh-800mAh. Optionally, in the electronic cigarette product, the capacity of the rechargeable battery can be 300-500mAH.

In another possible design of the present application, the battery 10 can be a rechargeable battery, and the capacity of the rechargeable battery can be 10mAH-80mAH, for example, 10mAH, 20mAH, 30mAH, 40mAH, 50mAH, 60mAH, 70mAH, 80mAH, which A battery of this capacity is smaller in size. As an example, the capacity of the rechargeable battery is 20mAH-40mAH. At this time, the battery volume is smaller and can be conveniently configured in small electronic products, such as wireless bluetooth earphones.

Optionally, the number of batteries 10 can be one or multiple. When there are multiple batteries, multiple batteries can be connected in parallel, in series, or mixed in series and parallel. It can be set according to actual needs. This embodiment is not correct. It defines.

Optionally, in a possible design of the present application, as shown in FIG. 7, a second resistor R2 and a second capacitor C2 are also provided between the battery 10 and the battery protection circuit Capacitor C2 is provided for filtering. In addition, in other embodiments of the present application, referring to the above-mentioned FIGS. 1A to 6 , the second resistor R2 and/or the second capacitor C2 may not be provided between the battery and the battery protection circuit 20 . In addition, in other embodiments of the present application, other circuits or electronic components may be provided between the battery and the battery protection circuit 20 , which may be determined according to actual needs, and are not limited in this embodiment.

The electronic device provided by the embodiment of the present application can ensure that when the battery protection circuit is powered on, the first The switch circuit enters and remains in the cut-off state, so that when the battery protection circuit with the load circuit is connected to the battery, there will be no problem that the battery frequently powers on and off the battery protection circuit and the load circuit due to unstable battery voltage. The problem that the electronic equipment may fail is reduced, and the service life of the electronic equipment is improved.

Other embodiments of the application will be readily apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any modification, use or adaptation of the application, these modifications, uses or adaptations follow the general principles of the application and include common knowledge or conventional technical means in the technical field not disclosed in the application . The specification and examples are to be considered exemplary only, with a true scope and spirit of the application indicated by the following claims.

It should be understood that the present application is not limited to the precise constructions which have been described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the application is limited only by the appended claims.

Claims (17)

1. A battery protection circuit, characterized in that it comprises: a power detection circuit, a first protection circuit, a first logic control circuit and a first switch circuit; The battery protection circuit includes a power supply terminal, a power ground terminal and a system terminal; the power supply terminal is connected to the first terminal of the power detection circuit, and the second terminal of the power detection circuit is connected to the power ground terminal , the output end of the power detection circuit is respectively connected to the first input end of the first protection circuit and the first input end of the first logic control circuit, and the output end of the first protection circuit is connected to the first input end of the first protection circuit. The second input terminal of a logic control circuit is connected, the output terminal of the first logic control circuit is connected to the control terminal of the first switch circuit, and the first terminal of the first switch circuit is connected to the ground terminal of the power supply or The power supply terminal is connected, and the second terminal of the first switch circuit is connected to the system terminal; The first logic control circuit is used to control the first switch circuit to turn off when the power detection circuit outputs a first level signal, and when the power detection circuit outputs a second signal, the first protection circuit Outputting a discharge protection signal, the battery protection circuit enters a discharge protection state, and when the battery protection circuit is in the discharge protection state, the first logic control circuit controls the first switch circuit to keep off. 2. The battery protection circuit according to claim 1, wherein the battery protection circuit further comprises a latch circuit; The first end of the latch circuit is connected to the output end of the power detection circuit, and the second end of the latch circuit is connected to the first protection circuit; The latch circuit enters a locked state when the power detection circuit outputs a second signal, and the latch circuit keeps outputting a protection trigger signal in the locked state, and the protection trigger signal is used to make the first protection circuit output discharge protection signal. 3. The battery protection circuit according to claim 2, wherein the first protection circuit comprises an over-discharge voltage protection circuit, the input terminal of the over-discharge voltage protection circuit is connected to the power supply terminal, and the The battery protection circuit also includes a third switch circuit and a second logic control circuit; The control terminal of the third switch circuit and the first input terminal of the second logic control circuit are both connected to the over-discharge voltage protection circuit, and the first terminal of the third switch circuit is connected to the second logic control circuit. The second input terminals of the circuit are all connected to the system terminal, and the output terminals of the second logic control circuit are respectively connected to the over-discharge voltage protection circuit and the latch circuit; When the first terminal of the first switch circuit is connected to the ground terminal of the power supply, the second terminal of the third switch circuit is connected to the power supply terminal, or, the first terminal of the first switch circuit is connected to the ground terminal of the power supply. When the power supply end is connected, the second end of the third switch circuit is connected to the power ground end; When the over-discharge voltage protection circuit outputs a discharge protection signal, the third switch circuit is turned on, the second logic control circuit outputs a first dormancy signal, and the over-discharge voltage protection circuit receives the first dormancy signal Continuously output the discharge protection signal, and the latch circuit releases the locked state when receiving the first dormancy signal. 4. The battery protection circuit according to claim 3, wherein the over-discharge voltage protection circuit comprises an over-discharge voltage protection unit, a delay protection circuit, a latch unit and a logic gate circuit; The output terminal of the latch circuit is connected to the first input terminal of the logic gate circuit, and the output terminal of the over-discharge voltage protection unit is connected to the delay protection circuit, the latch unit and the logic gate respectively. The second input end of the circuit is connected, the delay protection circuit is connected with the third input end of the logic gate circuit through the latch unit, and the output end of the logic gate circuit is respectively connected with the second logic control circuit The first input terminal of the said third switch circuit is connected with the second input terminal of the said first logic control circuit, and the output terminal of said second logic control circuit is respectively connected with said latch circuit, said The over-discharge voltage protection unit is connected to the delay protection circuit; wherein, when the logic gate circuit receives a protection trigger signal, the logic gate circuit outputs a discharge protection signal, the third switch circuit is turned on, and the The first logic control circuit controls the first switch circuit to keep off, the voltage of the system terminal is pulled up, and the second logic control circuit outputs a first sleep signal according to the discharge protection signal and the voltage signal of the system terminal, The first sleep signal is used to enable the discharge overvoltage protection function of the overdischarge voltage protection unit, shield the delay function of the delay protection circuit, and release the lock state of the latch circuit; or The output terminals of the latch circuit are respectively connected to the over-discharge voltage protection unit and the delay protection circuit, and the output terminals of the over-discharge voltage protection unit are respectively connected to the delay protection circuit and the latch unit connected to the first input terminal of the logic gate circuit, the delay protection circuit is connected to the second input terminal of the logic gate circuit through the latch unit, and the output terminals of the logic gate circuit are respectively connected to the The first input end of the second logic control circuit, the control end of the third switch circuit and the second input end of the first logic control circuit are connected, and the output ends of the second logic control circuit are respectively connected to the lock The storage circuit is connected to the over-discharge voltage protection unit; wherein, when the over-discharge voltage protection unit receives a protection trigger signal, the over-discharge voltage protection unit outputs the first protection signal, and the delay of the delay protection circuit The time function is shielded, the latch unit enters the locked state via the delay protection circuit, and in the locked state, the latch unit continues to output the delayed arrival signal, and the logic gate circuit according to the first protection signal and the delay When the arrival signal outputs a discharge protection signal, the third switch circuit is turned on and turned on, the first logic control circuit controls the first switch circuit to keep off, the voltage of the system terminal is pulled up, and the second logic control circuit Outputting a first dormancy signal according to the discharge protection signal and the voltage signal of the system terminal, the first dormancy signal is used to enable the discharge overvoltage protection function of the over-discharge voltage protection unit and release the latch circuit locked state. 5. The battery protection circuit according to claim 2, wherein the first protection circuit comprises a discharge overcurrent protection circuit, the input terminal of the discharge overcurrent protection circuit is connected to the system terminal, and the battery The protection circuit also includes a fourth switch circuit and a voltage detection circuit; The control terminal of the fourth switch circuit and the first input terminal of the voltage detection circuit are both connected to the discharge overcurrent protection circuit, and the first terminal of the fourth switch circuit is connected to the second input terminal of the voltage detection circuit. The input ends are all connected to the system end, and the output ends of the voltage detection circuit are respectively connected to the discharge overcurrent protection circuit and the latch circuit; When the first terminal of the first switch circuit is connected to the ground terminal of the power supply, the second terminal of the fourth switch circuit is connected to the ground terminal of the power supply, or, the first terminal of the first switch circuit is connected to the ground terminal of the power supply. When the power supply terminal is connected, the second terminal of the fourth switch circuit is connected to the power supply terminal; When the discharge overcurrent protection circuit outputs a discharge protection signal, the fourth switch circuit is turned on, and the voltage detection circuit outputs a discharge overcurrent hold when the discharge overcurrent protection circuit does not enter the discharge overcurrent protection state signal, the discharge overcurrent holding signal is used to make the discharge overcurrent protection circuit continuously output the discharge protection signal, and the voltage detection circuit outputs the discharge overcurrent protection signal when the discharge overcurrent protection circuit enters the discharge overcurrent protection state signal, and when the latch circuit receives the discharge overcurrent protection signal, the lock state is released. 6. The battery protection circuit according to claim 5, wherein the discharge overcurrent protection circuit comprises a discharge overcurrent protection unit, a delay protection circuit, a latch unit and a logic gate circuit; The output terminal of the latch circuit is connected to the first input terminal of the logic gate circuit, and the output terminal of the discharge overcurrent protection unit is connected to the delay protection circuit, the latch unit and the logic gate respectively. The second input end of the circuit is connected, the delay protection circuit is connected to the third input end of the logic gate circuit through the latch unit, and the output end of the logic gate circuit is respectively connected to the third input end of the voltage detection circuit. An input terminal, the control terminal of the fourth switch circuit, and the second input terminal of the first logic control circuit are connected, and the output terminal of the voltage detection circuit is connected to the latch circuit and the discharge overcurrent protection circuit respectively. The unit is connected to the delay protection circuit; wherein, when the logic gate circuit receives a protection trigger signal, the logic gate circuit outputs a discharge protection signal, the fourth switch circuit is turned on, and the first logic gate circuit The control circuit controls the first switch circuit to keep off, the voltage at the system terminal rises, and when the voltage at the system terminal is less than or equal to the discharge overcurrent threshold voltage, the discharge overcurrent protection unit does not enter the discharge overcurrent protection state, The voltage detection circuit outputs a discharge overcurrent protection signal. When the voltage at the system terminal is greater than the discharge overcurrent threshold voltage, the discharge overcurrent protection unit enters a discharge overcurrent protection state, and the voltage detection circuit outputs a discharge overcurrent protection signal. signal, wherein the discharge overcurrent hold signal is used to enable the discharge overcurrent protection function of the discharge overcurrent protection unit and shield the delay function of the delay protection circuit, and the latch unit passes through the delay When the protection circuit enters the locked state and continuously outputs the delayed arrival signal in the locked state, the logic gate circuit keeps outputting the discharge protection signal, and the discharge overcurrent protection signal is used to release the locked state of the latch circuit and clear the lock live; or The output terminals of the latch circuit are respectively connected to the discharge overcurrent protection unit and the delay protection circuit, and the output terminals of the discharge overcurrent protection unit are respectively connected to the delay protection circuit, the latch unit and the delay protection circuit. The first input terminal of the logic gate circuit is connected, the delay protection circuit is connected with the second input terminal of the logic gate circuit through the latch unit, and the output terminal of the logic gate circuit is connected with the voltage detection circuit respectively. The first input terminal of the circuit, the control terminal of the fourth switch circuit and the second input terminal of the first logic control circuit are connected; wherein, when the discharge overcurrent protection unit receives a protection trigger signal, the The discharge overcurrent protection unit outputs a first protection signal, the delay function of the delay protection circuit is shielded, and the latch unit enters a locked state through the delay protection circuit, and in the locked state, the latch unit The delayed arrival signal is continuously output, the logic gate circuit outputs a discharge protection signal according to the first protection signal and the delayed arrival signal, the fourth switch circuit is turned on, and the first logic control circuit controls the first switch circuit to maintain turn off, the voltage at the system end increases, and when the voltage at the system end is less than or equal to the discharge overcurrent threshold voltage, the voltage detection circuit outputs a discharge overcurrent hold signal, and the voltage at the system end is greater than the discharge overcurrent threshold voltage, the voltage detection circuit outputs a discharge overcurrent protection signal, wherein the discharge overcurrent hold signal is used to enable the discharge overcurrent protection function of the discharge overcurrent protection unit, and the discharge overcurrent protection signal is used for The locking state of the latch circuit is released and the latch is cleared. 7. The battery protection circuit according to claim 2, wherein the first protection circuit comprises a discharge overcurrent protection unit, a delay protection circuit, a latch unit, a first logic gate circuit and a second logic gate circuit , the battery protection circuit further includes a fourth switch circuit; The output terminal of the latch circuit is connected to the first input terminal of the second logic gate circuit, the input terminal of the discharge overcurrent protection unit is connected to the system terminal, and the output terminal of the discharge overcurrent protection unit respectively connected to the delay protection circuit, the latch unit and the first input end of the second logic gate circuit, the delay protection circuit through the latch unit and the first logic gate circuit The second input terminal is connected, the output terminal of the first logic gate circuit is connected with the second input terminal of the second logic gate circuit and the latch circuit respectively, and the output terminal of the second logic gate circuit is connected with the latch circuit. The control end of the fourth switch circuit is connected; When the first terminal of the first switch circuit is connected to the ground terminal of the power supply, the second terminal of the fourth switch circuit is connected to the ground terminal of the power supply, or, the first terminal of the first switch circuit is connected to the ground terminal of the power supply. When the power supply terminal is connected, the second terminal of the fourth switch circuit is connected to the power supply terminal; When the second logic gate circuit receives a protection trigger signal, the second logic gate circuit outputs a discharge protection signal, the fourth switch circuit is turned on, and the first logic control circuit controls the first switch circuit to maintain turn off, the voltage of the system terminal rises, so that the discharge overcurrent protection unit outputs the first protection signal, and the latch unit enters the locked state through the delay protection circuit, and in the locked state, the latch The unit continuously outputs the delayed arrival signal, the first logic gate circuit outputs the discharge overcurrent protection signal according to the first protection signal and the delayed arrival signal, and the second logic gate circuit continuously outputs the discharge protection signal, so When the above-mentioned latch circuit receives the discharge overcurrent protection signal, the latch state is released. 8. The battery protection circuit according to claim 2, wherein the first protection circuit comprises a discharge protection circuit, a delay protection circuit and a logic gate circuit; The first input end of the discharge protection circuit is connected to the second end of the latch circuit, and the output end of the discharge protection circuit is respectively connected to the delay protection circuit and the first input end of the logic gate circuit , the delay protection circuit is also connected to the second end of the latch circuit and the second input end of the logic gate circuit; When the latch circuit outputs a protection trigger signal, the discharge protection circuit outputs a first protection signal, and the delay function of the delay protection circuit is shielded, and the logic gate circuit outputs a discharge protection signal. 9. The battery protection circuit according to claim 2, wherein the first protection circuit comprises a discharge protection circuit, a delay protection circuit and a logic gate circuit; The input end of the discharge protection circuit is connected to the power supply end or the system end, and the output end of the discharge protection circuit is respectively connected to the input end of the delay protection circuit and the first input of the logic gate circuit. terminal connection, the output terminal of the delay protection circuit is connected with the second input terminal of the logic gate circuit, the third input terminal of the logic gate circuit is connected with the output terminal of the latch circuit, and the logic gate circuit The output terminal of the circuit is connected with the first logic control circuit; When the latch circuit outputs a protection trigger signal, the logic gate circuit outputs a discharge protection signal. 10. The battery protection circuit according to claim 2, wherein the first protection circuit comprises a discharge protection circuit, a zero-delay protection circuit, a delay protection circuit, a first latch unit, and a second latch unit , the third logic gate circuit and the fourth logic gate circuit; The first input end of the discharge protection circuit is connected to the second end of the latch circuit, and the output end of the discharge protection circuit is respectively connected to the zero-delay protection circuit, the delay protection circuit, the second A latch unit, the second latch unit, and the third logic gate circuit are connected, and the output end of the latch circuit is also connected with the zero-delay protection circuit and the delay protection circuit, and the The zero-delay protection circuit is connected to the first latch unit, the delay protection circuit is connected to the second latch unit, and both the first latch unit and the second latch unit are connected to the A fourth logic gate circuit is connected, the fourth logic gate circuit is connected to the third logic gate circuit, and the third logic gate circuit is connected to the first logic control circuit; When the latch circuit outputs a protection trigger signal, the discharge protection circuit outputs a first protection signal, the zero-delay protection circuit is triggered to work, the delay protection circuit does not work, and the first latch The unit enters the locked state without delay, and in the locked state, the first latch unit continues to output the first intermediate signal, the fourth logic gate circuit receives the first intermediate signal and continues to output the delayed arrival signal, and the first latch unit continues to output the delayed arrival signal. Three logic gate circuits output a discharge protection signal according to the delayed arrival signal and the first protection signal; or The first protection circuit includes a discharge protection circuit, a zero-delay protection circuit, a delay protection circuit, a latch unit and a third logic gate circuit; The first input end of the discharge protection circuit is connected to the second end of the latch circuit, and the output end of the discharge protection circuit is respectively connected to the zero-delay protection circuit, the delay protection circuit, the lock unit, the third logic gate circuit, the output terminal of the latch circuit is also connected with the zero delay protection circuit, the delay protection circuit, the zero delay protection circuit and the delay protection circuit The circuit is also connected to the latch unit, the latch unit is connected to the third logic gate circuit, and the third logic gate circuit is connected to the first logic control circuit; When the latch circuit outputs a protection trigger signal, the discharge protection circuit outputs a first protection signal, the zero-delay protection circuit is triggered to work, the delay protection circuit does not work, and the latch unit passes The zero-delay protection circuit enters a locked state, and in the locked state, the latch unit continues to output the delayed arrival signal, and the third logic gate circuit outputs the delayed arrival signal according to the delayed arrival signal and the first protection signal discharge protection signal. 11. The battery protection circuit according to any one of claims 1 to 10, wherein the power detection circuit comprises a charging circuit and a threshold detection unit; The first terminal of the charging circuit is connected to the power supply terminal, the second terminal of the charging circuit is connected to the ground terminal of the power supply, and the third terminal of the charging circuit is connected to the input terminal of the threshold detection unit , the output end of the threshold detection unit is respectively connected to the first input end of the first protection circuit and the first input end of the first logic control circuit; The threshold detection unit outputs a first level signal when its input voltage satisfies a first condition, and the output signal changes from the first level signal to a second level signal when its input voltage meets a second condition, so The second signal is the second level signal or an edge signal from the first level signal to the second level signal. 12. The battery protection circuit according to claim 11, wherein the charging circuit comprises a first charging element and a first capacitor; The first end of the first charging element is connected to the power supply end, the second end of the first charging element is connected to the first end of the first capacitor, and the first charging element and the The connection point of the first capacitor is connected to the input terminal of the threshold detection unit, and the second terminal of the first capacitor is connected to the ground terminal of the power supply; Wherein, the first charging element is a resistor, a depletion switch, a capacitor or a current source; The threshold detection unit outputs a first level signal when its input voltage is less than a first voltage threshold, and the output signal changes from the first level signal to a second level signal when its input voltage reaches the first voltage threshold . 13. The battery protection circuit according to claim 11, wherein the charging circuit comprises a first capacitor and a first charging element; The first end of the first capacitor is connected to the power supply end, the second end of the first capacitor is connected to the first end of the first charging element, and the first capacitor and the first A connection point of a charging element is connected to the input end of the threshold detection unit, and a second end of the first charging element is connected to the ground end of the power supply; Wherein, the first charging element is a resistor, a depletion switch, a current source or a capacitor; The threshold detection unit outputs a first level signal when its input voltage is greater than a first voltage threshold, and the output signal changes from the first level signal to a second level signal when its input voltage drops to less than or equal to the first voltage threshold. two-level signal. 14. The battery protection circuit according to claim 11, wherein the power detection circuit further comprises a second switch unit, the first terminal of the second switch unit is connected to the power supply terminal, and the first The second terminal of the second switch unit is connected to the input terminal of the threshold detection unit, and the control terminal of the second switch unit is connected to the output terminal of the threshold detection unit; When the threshold detection unit outputs a first level signal, the second switch unit is turned off, and when the threshold detection unit outputs a second level signal, the second switch unit is turned on. 15. The battery protection circuit according to any one of claims 1 to 10, wherein when power is turned on, the time required for the first protection circuit to control the conduction of the first switch circuit is longer than the time required for the power detection A circuit controls the time required for the first switching circuit to be turned off. 16. The battery protection circuit according to any one of claims 1 to 10, wherein the circuits other than the first switch circuit of the battery protection circuit are located on the same chip, and the first switch circuit is located on another chip. On one chip, the power supply terminal is a power supply pin, the power ground terminal is a power ground pin, and the system terminal is a system pin; or, The battery protection circuit is located on the same chip, the power supply terminal is a power supply pin, the power ground terminal is a power ground pin, and the system terminal is a system pin. 17. An electronic device, characterized in that it comprises: Battery; charging device and/or load; The battery protection circuit according to any one of claims 1 to 16; The power supply end and the power ground end of the battery protection circuit are correspondingly connected to the positive pole and the negative pole of the battery, the system end of the battery protection circuit is connected to the charging device and/or the load, and the charging device and/or the The load is also used to connect to the positive or negative pole of the battery.