CN201243220Y - Simple charging circuit for mobile phone battery through hand generator - Google Patents

Abstract

The utility model relates to a simple charging circuit for charging a mobile phone battery by a hand dynamo, in particular to a circuit for directly charging and protecting batteries by a controllable hand dynamo. The charging circuit saves a plurality of auxiliary elements, lowers cost and greatly reduces the volume; the circuit realizes the monitoring to the battery electric quantity and the battery charging and protects the damages of the battery caused by over charging, thus simply and widely solving the problem that the equipment is emergently charged under the condition that various kinds of hand electronic equipment do not have power supply with lower cost.

Description

A simple charging circuit for charging mobile phone batteries through a hand-cranked generator

technical field

The utility model relates to a simple charging circuit for charging a mobile phone battery through a hand-operated generator, more specifically, relates to a circuit which can control the hand-operated generator to directly charge the battery and protect the battery.

Background technique

At present, there are many chargers on the market for charging mobile phone batteries with hand-cranked generators, which can be used for emergency charging when there is no power supply. The alternating current generated by the hand motor is rectified and filtered by the bridge, and after the voltage stabilization circuit stabilizes, a small current is sent to the charging circuit of the device and then sent to the battery for charging. In this charging method, the current will have a certain loss, and only about 60% of the battery reaches the battery, which cannot avoid the power consumption problem, indirectly prolonging the use time of the charger and reducing the life of the charger; at the same time, the current of the hand generator itself is unstable. It is easy to cause overcharge damage to the battery.

Utility model content

The technical problem to be solved by the utility model is to reduce the loss caused by charging the battery through the charging circuit of the mobile phone, and the problems such as overcharging damage to the battery caused by direct charging of the battery. In view of the above problems, the utility model provides a simple charging circuit for charging the battery of a mobile phone through a hand-operated generator, more specifically, relates to a circuit that can control the hand-operated generator to directly charge the battery and protect the battery.

The technical solution adopted by the utility model to solve the technical problem is to provide a simple charging circuit for charging the battery of a mobile phone through a hand-operated generator. The charging circuit includes a voltage divider circuit connected to the battery in the mobile phone, a control circuit connected to the voltage divider output end of the voltage divider circuit, and a control circuit connected between the rectification filter circuit and the battery and controlled by the control circuit. broken switching circuit.

In the simple charging circuit for charging the battery of a mobile phone through a hand-operated generator described in the utility model, the alternating current generated by the hand-operated generator is bridge-type rectified and filtered through the rectifier and filter circuit, and after the voltage stabilization circuit stabilizes, a small current is sent to To the charging circuit, the charging circuit judges and controls whether the battery is charged or not.

In the charging circuit described in the utility model, it includes a control circuit composed of Q2, Q3, R2, and R5, and judges whether to charge the battery according to the voltage state of the battery, and is controlled by Q1 (P channel MOSFET) and R1. Unit, to perform the final operation on whether to charge or not; the voltage divider circuit composed of R3 and R4 divides the voltage of the circuit to change the output voltage, the current input terminal of the hand generator (VCHR_IN), and the output terminal of the mobile phone charging current ( VBAT). The above circuit control and process are: when the battery voltage is low, the voltage of V _a is also low, Q2 is turned off, Q3 is turned on, V _gs of MOSFET Q1 = V _R1 , Q1 is turned on, and the battery starts charging. As the battery voltage continues to increase, V _a gradually increases. When V _a reaches 0.7V, Q2 is turned on, Q3 is turned off, V _gs =0, Q1 is turned off, and the battery stops charging.

The utility model solves the problem of current loss through the circuit of the mobile phone. At the same time, the circuit is provided with a protection device to timely shut off the charging circuit after the battery is fully charged, so as to avoid overcharging damage to the battery. The invention directly charges the battery through a hand generator, and when the voltage reaches 4.15V, the generator will stop supplying power to the battery without affecting the battery.

Description of drawings

In the attached picture:

Fig. 1 is a schematic diagram of the charging circuit of the present invention.

Detailed ways

The utility model relates to a simple charging circuit for charging the battery of a mobile phone through a hand-operated generator, more specifically, a circuit that can control the hand-operated generator to directly charge the battery and protect the battery. The charging circuit is a circuit that controls the hand generator to directly charge the battery.

As shown in Figure 1, the control circuit is composed of Q2, Q3, R2, and R5. According to the voltage state of the battery, it is judged whether to charge the battery. The controlled unit is composed of Q1 (P-channel MOSFET) and R1. Do the final execution operation; the voltage divider circuit composed of R3 and R4 divides the voltage of the circuit to change the output voltage; when the battery voltage is low, the voltage of V _a is also low, Q2 in the control circuit is cut off, Q3 is turned on, V _gs of MOSFET Q1 in the switching circuit = V _R1 , Q1 is turned on, and starts to charge the battery; as the battery voltage continues to rise, V _a also gradually increases, and when V _a reaches 0.7V, it is composed of R3 and R4 The voltage divider circuit in the control circuit changes the output voltage so that Q2 in the control circuit is turned on and Q3 is turned off, so V _gs of the switch circuit = 0, Q1 is turned off, and charging of the battery is stopped. C1 acts as a filter, and diode D1 prevents battery current from flowing backward. In the whole charging circuit, the control circuit, switch circuit and voltage divider circuit can adjust the resistance value of each resistor according to different batteries, and control the charging current so that the battery will not be overcharged and damaged during charging.

By integrating a hand generator, a rectifier filter circuit and a charging circuit that can control whether to charge the battery according to the battery voltage, the battery can be directly charged in an emergency when the battery of the mobile phone is dead and there is no power to charge; by using In the utility model, this type of charger uses fewer components, has small volume, low power consumption, low cost and high efficiency, and is applicable to various hand-held electronic devices.

Claims (3)

1. A simple charging circuit for charging the battery of a mobile phone by a hand generator, characterized in that the charging circuit includes: a voltage divider circuit connected to the battery in the handheld electronic device, and a voltage divider circuit connected with the voltage divider circuit The control circuit connected to the output end of the voltage division, and the switch circuit connected between the rectification filter circuit and the battery and controlled by the control circuit. 2. The simple charging circuit for charging the battery of a mobile phone by a hand generator according to claim 1, wherein the voltage dividing circuit includes resistors R3 and R4 connected in series between the positive pole and the negative pole of the battery; Include resistance R2, R3, switch tube Q2, Q3 in the described control circuit, its connection relationship is that the collector of Q2 is connected to R5 and then connected to the current output terminal (VBAT), the emitter is connected to the negative pole of the power supply, and the base is connected to R3, Between R4; the collector of Q3 is connected to the base of R1 and Q1 in the switch circuit, the emitter is connected to R2 and then connected to the negative pole of the power supply, and the base is connected between Q2 and R5; the switch circuit includes Resistor R1, field effect transistor Q1, the connection relationship is that Q1 and R1 are connected in parallel, the switch terminal S of Q1 is connected to the current input terminal (VCHR_IN), the other switch terminal D of Q1 is connected to the current output terminal (VBAT), the base of Q1 pole is connected to the collector of Q3. 3. The simple charging circuit for charging the battery of a mobile phone through a hand generator according to claim 2, characterized in that the charging circuit also includes a capacitor C1, a diode D1, the positive pole of the capacitor C1 and the current input terminal (VCHR_IN) Connection, the negative pole is connected to the negative pole of the battery; the negative pole of the diode is connected to the current input terminal (VCHR_IN), and the positive pole is connected to the switch terminal S of Q1.

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