CN206211566U - A kind of charger detects protection circuit and charger - Google Patents

Abstract

The utility model provides a kind of charger and detects protection circuit and charger, including：Control module, voltage detection module and current detection module, the input of the voltage detection module are connected with the output port of charger, the voltage of the output port for detecting the charger；The input of the current detection module is connected with the output end of the voltage detection module, for detecting the electric current of the output port of the charger and exporting the electric current to the charging port, the output termination charging port of the current detection module;Test side of the control module respectively with the voltage detection module and the current detection module is connected, for according to the voltage and current output protection signal.Through the above way, a kind of charger detection protection circuit that the utility model is provided, makes charger be disconnected when electric current is excessive, and ensure that user can easily judge charger operation situation.

Description

A charger detection and protection circuit and charger

technical field

The utility model relates to a charger, in particular to a charger detection and protection circuit.

Background technique

At present, there are generally the following types of mobile phone chargers on the market: one is to convert AC 220VAC to DC 5VDC, and apply a step-down circuit to achieve an output voltage of 5V/1A; the other is to convert DC to DC, and apply a step-down circuit to achieve 5V/1A; It is through some 4.2V lithium battery application boost circuit to realize the output of 5V/1A, and the charger is connected to the mobile phone with a cable for charging. However, the quality of chargers on the market is uneven. Some inferior chargers may output a voltage higher than 5V or a current higher than 1A, causing damage to the mobile phone, and even endangering the personal safety of the user.

Utility model content

The purpose of the utility model is to provide a charger detection and protection circuit to ensure that the output voltage and current are within a safe range and ensure the safety of mobile phones and users.

In order to achieve the above object, the utility model provides a charger detection protection circuit, the charger detection protection circuit, including: a control module, a voltage detection module and a current detection module, the input terminal of the voltage detection module and the charger The output port is connected to detect the voltage of the output port of the charger; the input terminal of the current detection module is connected to the output terminal of the voltage detection module, which is used to detect the current of the output port of the charger and The current is output to the charging port, and the output terminal of the current detection module is connected to the charging port; the control module is respectively connected to the detection terminals of the voltage detection module and the current detection module, and is used for charging according to the voltage and current output protection signals.

According to the charger detection and protection circuit of the present invention, the control module is respectively connected with the voltage detection module for detecting the voltage of the output port of the charger and the current detection module for detecting the current of the output port of the charger, and according to the voltage detection module and The voltage and current detected by the current detection module output a protection signal to ensure that the voltage and current output by the charger are within a safe range, ensuring the safety of the mobile phone and the user.

Preferably, the charger detection and protection circuit further includes an indicating device connected to the control module, and the indicating device is used to prompt that the charger is working abnormally or normally according to the output protection signal.

Preferably, the indicating device is an LED light or a buzzer.

Preferably, the voltage detection module includes a first resistor and a second resistor connected in series, one end of the first resistor is connected to the output port of the charger, and the other end of the first resistor is connected to one end of the second resistor , the other end of the second resistor is connected to the input end of the current detection module, and the other end of the first resistor is a detection end connected to the control module.

Preferably, the current detection module includes an operational amplifier, a third resistor, a fourth resistor, a fifth resistor, and a sixth resistor, one end of the third resistor is the input terminal of the current detection module, connected to the second The other end of the resistance, the other end of the third resistance is the output end of the current detection module, one end of the fourth resistance is connected to the positive input end of the operational amplifier, and one end of the fifth resistance is connected At the negative input terminal of the operational amplifier, the sixth resistor is connected between the fifth resistor and the output terminal of the operational amplifier, and the other ends of the fourth resistor and the fifth resistor are respectively connected At both ends of the third resistor, the output terminal of the operational amplifier is connected to the control module.

Preferably, the charger detection and protection circuit further includes a protection module, the protection module is connected between the current detection module and the charging port, and connected to the control module, when the current detected by the current detection module When greater than a certain threshold, the control module controls the protection module to disconnect.

Preferably, the protection module includes a seventh resistor and a MOS transistor, the seventh resistor is connected between the gate and the source of the MOS transistor, and the source of the MOS transistor is connected to the output of the current detection module terminal, the drain of the MOS tube is connected to the output port of the charger, the gate of the MOS tube is connected to the control module, when the current detected by the current detection module is greater than a certain threshold, the control module Control the MOS tube to be disconnected. Preferably, the charger detection and protection circuit further includes a voltage stabilization circuit, the voltage stabilization circuit is connected between the output port of the charger and the control module, and is used to supply power to the control module, and the voltage stabilization circuit The voltage circuit includes a first capacitor, a second capacitor, a third capacitor, a fourth capacitor and a three-terminal voltage regulator, the input terminal of the three-terminal voltage regulator is connected to the output port of the charger, and the three-terminal voltage regulator The output terminal of the regulator is connected to the control module, the first capacitor and the second capacitor are connected in parallel between the input terminal and the ground terminal of the three-terminal voltage regulator, and the third capacitor and the first capacitor The four capacitors are connected in parallel between the output terminal of the three-terminal regulator and the ground terminal.

The utility model also provides a charger, including the above-mentioned charger detection and protection circuit.

Description of drawings

The above-mentioned and/or additional aspects and advantages of the utility model will become apparent and easy to understand from the following description of the embodiments in conjunction with the accompanying drawings, wherein:

Figure 1 is a schematic diagram of the charging port connection;

Fig. 2 is a control schematic diagram of a charger detection and protection circuit according to an embodiment of the present invention;

FIG. 3 is a circuit diagram of a charger detection and protection circuit according to an embodiment of the present invention.

detailed description

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are only used to explain the present invention, and cannot be construed as limiting the present invention.

The following disclosure provides many different embodiments or examples for realizing different structures of the present invention. To simplify the disclosure of the present invention, components and arrangements of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the utility model. Furthermore, the present invention may repeat reference numerals and/or letters in different instances. This repetition is for the purpose of simplicity and clarity and does not in itself indicate a relationship between the various embodiments and/or arrangements discussed.

In the description of the present utility model, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", "connection" and "connection" should be understood in a broad sense, for example, it can be a mechanical connection or an electrical connection , may also be the internal communication of two elements, may be directly connected, or may be indirectly connected through an intermediary, and those of ordinary skill in the art can understand the specific meanings of the above terms according to specific situations.

These and other aspects of embodiments of the present invention will become apparent with reference to the following description and drawings. In these descriptions and drawings, some specific implementations of the embodiments of the present invention are specifically disclosed to represent some ways of implementing the principles of the embodiments of the present invention, but it should be understood that the embodiments of the present invention The range is not limited by this. On the contrary, the embodiments of the present invention include all changes, modifications and equivalents falling within the spirit and scope of the appended claims.

In the following, a mobile phone is taken as an example to describe a charger detection and protection circuit according to an embodiment of the present invention.

As shown in Figure 1, the output port 10 of the charger is connected to the charging port 12 of the mobile phone through a charger detection protection circuit 11. Before the charger charges the mobile phone, the voltage and current of the output port 10 of the charger are not known. Next, the charger detection and protection circuit 11 first detects the output port 10 of the charger, and when the charger detection and protection circuit 11 indicates that the voltage and current are within a safe range, the charger can charge the mobile phone; when the charger detection and protection circuit 11 When the indicated voltage and/or current is not within the safe range, the charger cannot charge the mobile phone.

Fig. 2 is a schematic diagram of a charger detection and protection circuit 11 according to an embodiment of the present invention, including: a control module 101, a voltage detection module 103 and a current detection module 104, the input terminal of the voltage detection module 103 and the output of the charger The port 10 is connected to detect the voltage of the output port 10 of the charger; the input end of the current detection module 104 is connected to the output end of the voltage detection module 103, and is used to detect the output port 10 of the charger and output the current to the charging port 12, the output terminal of the current detection module 104 is connected to the charging port 12; the control module 101 is connected with the voltage detection module 103 and the current detection module 104 respectively The detection terminal is connected to output a protection signal according to the voltage and current.

The charger detection and protection circuit according to an embodiment of the present utility model connects the control module with the voltage detection module and the current detection module respectively, and outputs a protection signal according to the voltage and current detected by the voltage detection module and the current detection module , to ensure that the voltage and current output by the charger are within a safe range, ensuring the safety of mobile phones and users.

In this embodiment, the control module 101 is a single-chip microcomputer U1, as shown by 101 in FIG. 3 , including RC1 port, RC2 port, RC5 port, RA3 port, RA4 port, VDD port and VSS port.

As shown in FIG. 3 , the voltage detection module 103 in this embodiment includes a first resistor R1 and a second resistor R2 connected in series. One end of the first resistor R1 is connected to the output port 10 of the charger, the other end of the first resistor R1 is connected to one end of the second resistor R2, and the other end of the second resistor R2 is connected to the input end of the current detection module 104 , the other end of the first resistor R1 is a detection terminal connected to the RA3 port of the single-chip microcomputer U1. The voltage of the output port 10 of the charger passes through the first resistor R1, and then is input to the single-chip microcomputer U1 through the port RA3, and the single-chip microcomputer U1 collects the voltage of the output port of the charger through the port RA3.

As shown in FIG. 3 , in this embodiment, the current detection module 104 includes: an operational amplifier U3, a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6. One end of the third resistor R3 is The input end of the current detection module 104 is connected to the other end of the second resistor R2, the other end of the third resistor R3 is the output end of the current detection module 104, and one end of the fourth resistor R4 is connected to The positive input terminal of the operational amplifier U3, one end of the fifth resistor R5 is connected to the negative input terminal of the operational amplifier U3, and the sixth resistor R6 is connected between the fifth resistor R5 and the operational amplifier Between the output terminals of U3, the other ends of the fourth resistor R4 and the fifth resistor R5 are respectively connected to the two ends of the third resistor R3, and the output terminal of the operational amplifier is connected to the RA4 port of the single-chip microcomputer U1 . The single-chip microcomputer U1 collects the current of the output port of the charger through the RA4 port.

As a preferred implementation of this embodiment, the charger detection and protection circuit 11 further includes: a voltage stabilizing circuit 100, the voltage stabilizing circuit 100 is connected between the output port 10 of the charger and the VDD port of the single-chip microcomputer U1 Between them, it is used to supply power to the microcontroller U1. Specifically, the voltage stabilizing circuit 100 is shown as 100 in FIG. 3 , including: a first capacitor C1, a second capacitor C2, a three-terminal regulator U2, a third capacitor C3, and a fourth capacitor C4. The first The capacitor C1 and the second capacitor C2 are connected in parallel between the input terminal of the three-terminal voltage regulator U2 and the ground, and the third capacitor C3 and the fourth capacitor C4 are connected in parallel to the three-terminal voltage regulator Between the output terminal of U2 and the ground terminal, the input terminal of the three-terminal voltage regulator U2 is connected to the output port 10 of the charger, and the output terminal of the three-terminal voltage regulator U2 is connected to the VDD port of the single-chip microcomputer U1. The output voltage of the charger output port 10 flows in from the input terminal of the charging detection protection circuit 11, flows to the three-terminal regulator U2 after being filtered by the first capacitor C1 and the second capacitor C2, and is output from the three-terminal regulator U2 and passes through the third The third capacitor C3 and the fourth capacitor C4 filter, and output a stable voltage for the operation of the single-chip microcomputer U1.

As another preferred implementation of this embodiment, the charger detection and protection circuit 11 further includes: an indicating device 102, and the indicating device 102 is an LED light or a buzzer. Specifically, the indicating device 102 is shown as 102 in FIG. 3 , and includes: an eighth resistor R8, a ninth resistor R9, a green light L1, and a red light L2. The eighth resistor R8 is connected between the RC1 port of the single-chip microcomputer U1 and the green light L1. Between, the ninth resistor R9 is connected between the RC2 port of the single-chip microcomputer U1 and the red light L2, and the indication mode of the indicator device 102 is: L1 lights up green, L2 off means it can be charged; L1 off, L2 lights up red means Can not be charged.

As yet another preferred implementation of this embodiment, the charger detection protection circuit 11 further includes: a protection module 105, the protection module 105 is respectively connected to the control module 101 and the current detection module 104, when the When the current detected by the current detection module 104 is greater than a certain threshold, the control module 101 controls the protection module 105 to disconnect. Specifically, the protection module 105, as shown by 105 in FIG. 3 , includes a seventh resistor R7 and a MOS transistor T1, the seventh resistor R7 is connected between the gate and the source of the NMOS transistor T1, and the The source of the MOS transistor T1 is connected to the output terminal of the current detection module 104, the gate of the MOS transistor T1 is connected to the RC5 port of the single-chip microcomputer U1, and the drain of the MOS transistor T1 is connected to the charging port of the mobile phone. When the current detected by the current detection module 104 is less than or equal to a certain threshold, the RC5 port of the single-chip microcomputer outputs a high level, and the NMOS transistor T1 is turned on; otherwise, the RC5 port of the single-chip microcomputer outputs a low level, and the NMOS transistor T1 does not conduction.

The working principle of the charger detection and protection circuit 11 in this embodiment will be described below with reference to FIG. 3 .

First connect the charger to the mains, and the charger detection and protection circuit 11 performs voltage detection on the output port 10 of the charger. When the single-chip microcomputer U1 detects that the voltage is not within the safe range, then the RC2 port of the single-chip microcomputer U1 outputs a low level, the L1 light is off, and the L2 light is red. At this time, the mobile phone cannot be charged; when the single-chip microcomputer U1 detects If the voltage is within the safe range, then the RC1 port of the single-chip microcomputer U1 outputs a low level, the green light of L1 is on, and the light of L2 is off. At this time, the charging port 12 of the mobile phone can be connected to the charger detection protection circuit 11 for charging current detection.

If the single-chip microcomputer U1 detects that the charging current is within the safe range, the RC5 port of the single-chip microcomputer U1 outputs a high level, the MOS tube is turned on, the RC1 port outputs a low level, the green light of L1 is on, and the light of L2 is off, indicating that it can Charging; if the single-chip microcomputer U1 detects that the charging current is not within the safe range, the RC5 port of the single-chip microcomputer U1 outputs a low level, the MOS tube is disconnected, the RC2 port outputs a low level, the L1 light is off, and the L2 light is red The light indicates that charging is not possible, and the charging port 12 of the mobile phone is disconnected from the charger detection protection circuit 11.

The utility model also provides a charger, which includes the above-mentioned charger detection and protection circuit 11 .

In the charger according to an embodiment of the present invention, the control module is respectively connected to the voltage detection module and the current detection module, and according to the voltage and current detected by the voltage detection module and the current detection module, the output protection signal to ensure that the voltage and current output by the charger are within a safe range, ensuring the safety of mobile phones and users.

The above is only an embodiment of the utility model, and does not limit the patent scope of the utility model. Any equivalent structure or equivalent process conversion made by using the content of the specification of the utility model, or directly or indirectly used in other related technologies Fields are all included in the scope of patent protection of the utility model in the same way.

In the description of this specification, descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structures, materials or features are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, those skilled in the art can understand that various changes and modifications can be made to these embodiments without departing from the principle and spirit of the present invention , replacements and modifications, the scope of the present utility model is defined by the appended claims and their equivalents.

Claims (9)

1. a kind of charger detects protection circuit, it is characterised in that include：Control module, voltage detection module and current detecting Module, the input of the voltage detection module is connected with the output port of charger, the output for detecting the charger The voltage of port；The input of the current detection module is connected with the output end of the voltage detection module, for detecting State the electric current of the output port of charger and export the electric current to charging port, the output termination of the current detection module Charging port;Test side of the control module respectively with the voltage detection module and the current detection module is connected, and uses According to the voltage and current output protection signal.

2. charger according to claim 1 detects protection circuit, it is characterised in that also including connecting with the control module The instruction device for connecing, the instruction device is for the charger operation exception according to the output protection signal prompt or just Often.

3. charger according to claim 2 detection protection circuit, it is characterised in that the instruction device be LED or Buzzer.

4. charger according to claim 1 detects protection circuit, it is characterised in that the voltage detection module includes string Connection first resistor and second resistance, the output port of a termination charger of the first resistor, the first resistor One end of another termination second resistance, the input of another termination current detection module of the second resistance, institute The other end of first resistor is stated for test side, is connected with the control module.

5. charger according to claim 4 detects protection circuit, it is characterised in that the current detection module includes fortune Amplifier, 3rd resistor, the 4th resistance, the 5th resistance, the 6th resistance are calculated, one end of the 3rd resistor is the current detecting The input of module, connects the other end of the second resistance, and the other end of the 3rd resistor is the current detection module Output end a, end of the 4th resistance is connected on the positive input of the operational amplifier, a termination of the 5th resistance In the negative input of the operational amplifier, the 6th resistance is connected on the defeated of the 5th resistance and the operational amplifier Go out between end, the other end of the 4th resistance and the 5th resistance is connected on the two ends of the 3rd resistor, the fortune respectively The output end for calculating amplifier connects the control module.

6. charger according to claim 1 detects protection circuit, it is characterised in that also including protection module, the guarantor Shield module is connected between the current detection module and charging port, and is connected with the control module, when the current detecting When the electric current that module is detected is more than certain threshold value, the control module controls the protection module to disconnect.

7. charger according to claim 6 detects protection circuit, it is characterised in that the protection module includes the 7th electricity Resistance and metal-oxide-semiconductor, the 7th resistance are connected between the grid of the metal-oxide-semiconductor and source electrode, and the source electrode of the metal-oxide-semiconductor connects the electric current The output end of detection module, the drain electrode of the metal-oxide-semiconductor connects the output end that the charger detects protection circuit, the metal-oxide-semiconductor Grid connects the control module, when the electric current that the current detection module is detected is more than certain threshold value, the control module The metal-oxide-semiconductor is controlled to disconnect.

8. charger according to claim 1 detects protection circuit, it is characterised in that also including mu balanced circuit, described steady Volt circuit is connected between the output port of the charger and the control module, for being powered for the control module, institute Stating mu balanced circuit includes the first electric capacity, the second electric capacity, the 3rd electric capacity, the 4th electric capacity and three terminal regulator, the three terminal regulator The input termination charger output port, the output of the three terminal regulator terminates the control module, described first Electric capacity and second electric capacity are connected between the input of the three terminal regulator and ground terminal in parallel, the 3rd electric capacity and institute The 4th electric capacity is stated to be connected in parallel between the output end of the three terminal regulator and ground terminal.

9. a kind of charger, it is characterised in that detect protection circuit including any described charger of claim 1-8.