Miniaturized wall-mounted 18W lithium battery power supply charger

Abstract

The utility model discloses a miniaturized wall-mounted 18W lithium battery power supply charger. An internal circuit of the charger comprises an AC input circuit, an EMI rectification filter circuit, a power conversion circuit, a rectification filter output circuit, a constant current lamp conversion circuit, a feedback voltage stabilizing circuit and a PWM master control IC circuit. According to the miniaturized wall-inserting type 18W lithium battery power supply charger, the PWM master control IC circuit, the constant-voltage-to-constant-current circuit and the feedback voltage stabilizing circuit are designed, so that the power supply charger has the functions of precise power control, constant-voltage and constant-current charging and color conversion of a charging indicating lamp, and is good in charging effect, energy-saving and environment-friendly; the whole circuit structure design is controlled by a control chip, peripheral circuits are few, the structure is compact, and the size miniaturization of the charger is facilitated.

Description

Technical Field

[0001] This utility model belongs to the field of power charger technology, specifically relating to a miniaturized wall-mounted 18W lithium battery power charger. Background Technology

[0002] Small household appliances and consumer electronics products generally use wall-mounted and desktop lithium battery chargers. Compared to desktop lithium battery chargers, wall-mounted chargers are smaller and have lower power. However, due to their miniaturization, existing wall-mounted chargers have relatively simple functions and internal structures, resulting in imprecise power control, poor energy efficiency, or the lack of constant current and constant voltage charging capabilities, leading to poor charging performance. Therefore, in the context of energy scarcity and the promotion of energy conservation and environmental protection, it is necessary to design wall-mounted lithium battery chargers that balance miniaturization, precise power control, and good charging performance. Utility Model Content

[0003] The purpose of this invention is to address the above-mentioned problems by providing a miniaturized 18W wall-mounted lithium battery charger, which achieves precise power control and good charging performance while maintaining a small size.

[0004] This utility model is achieved through the following technical solution:

[0005] A miniaturized 18W wall-mounted lithium battery charger includes an internal circuit comprising an AC input circuit, an EMI rectifier and filter circuit, a power conversion circuit, a rectifier and filter output circuit, a constant current indicator circuit, a feedback voltage regulator circuit, and a PWM main control IC circuit. The output of the AC input circuit is connected to the input of the rectifier bridge BD1 of the EMI rectifier and filter circuit. A filter circuit composed of filter capacitors C1 and C2 and inductors L1 and L2 is connected between the outputs of the rectifier bridge BD1. The positive terminal of the output of the EMI rectifier and filter circuit is connected to the positive terminal of the first primary winding of the power transformer T1 in the power conversion circuit. The negative terminal of the first primary winding is connected to the output control terminal of the PWM control chip U1 in the PWM main control IC circuit. The second primary winding of the power transformer T1 supplies power to the... The chip U1 provides the operating voltage; the output of the first winding of the secondary side of the power transformer T1 of the power conversion circuit is connected to the charging output interface of the charger after rectification and filtering by the rectifier and filter output circuit; the positive terminal of the second winding of the secondary side of the power transformer T1 of the power conversion circuit supplies power to the chip U2 of the constant current lamp switching circuit, and the chip U2 is a constant voltage and constant current dual-loop control chip with color conversion function of charging indicator LED1; the constant current lamp switching circuit is connected to the rectifier and filter output circuit to form the control loop input of the chip U2, the control output of the chip U2 is connected to the input terminal of the optocoupler PC1 of the feedback voltage regulator circuit, and the output terminal of the optocoupler PC1 is connected to the feedback input terminal of the PWM control chip U1 of the PWM main control IC circuit.

[0006] Furthermore, the AC input circuit is equipped with an overcurrent protection fuse F1 and a lightning protection varistor ZR1.

[0007] Furthermore, the PWM control chip U1 is model CJW3561DD.

[0008] Furthermore, the chip U2 is model number ME4312.

[0009] Furthermore, the charging indicator LED1 is a dual-channel indicator, which is connected to two different colored control pins of the chip U2.

[0010] The beneficial effects of this utility model are: 1. The miniaturized wall-mounted 18W lithium battery power charger of this utility model is designed with a PWM main control IC circuit, a constant current indicator circuit and a feedback voltage regulator circuit, which enables the power charger to have precise power control and constant voltage and constant current charging functions, as well as charging indicator light color changing function, resulting in good charging effect and energy saving and environmental protection; 2. The entire circuit structure design adopts control chip control, with fewer peripheral circuits and a compact structure, which is conducive to miniaturization of the charger. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the principle of this utility model.

[0012] Figure 2 This is the circuit schematic diagram of this utility model.

[0013] In the diagram, 1 is the AC input circuit, 2 is the EMI rectifier and filter circuit, 3 is the power conversion circuit, 4 is the rectifier and filter output circuit, 5 is the constant current lamp-turning circuit, 6 is the feedback voltage regulator circuit, and 7 is the PWM main control IC circuit. Detailed Implementation

[0014] The present invention will be further illustrated below with reference to specific examples and accompanying drawings.

[0015] like Figure 1 , Figure 2 As shown, a miniaturized wall-mounted 18W lithium battery power charger includes an internal circuit comprising an AC input circuit 1, an EMI rectifier and filter circuit 2, a power conversion circuit 3, a rectifier and filter output circuit 4, a constant current lamp-turning circuit 5, a feedback voltage regulator circuit 6, and a PWM main control IC circuit 7.

[0016] The AC input circuit 1 is equipped with an overcurrent protection fuse F1 and a lightning protection varistor ZR1. The output terminal of the AC input circuit 1 is connected to the input terminal of the rectifier bridge BD1 of the EMI rectifier filter circuit 2. The output terminals of the rectifier bridge BD1 are connected to a filter circuit composed of filter capacitors C1 and C2 and inductors L1 and L2. The positive terminal of the output terminal of the EMI rectifier filter circuit 2 is connected to the positive terminal of the primary winding T1A of the power transformer T1 of the power conversion circuit 3. The negative terminal of the primary winding T1A is connected to the output control terminal of the PWM control chip U1 of the PWM main control IC circuit 7. The chip U1 is model CJW3561DD. The primary winding T1B of the power transformer T1 provides the operating voltage to the chip U1. The positive terminal of the primary winding T1B is connected to the VDD pin of the chip U1 through diode D2, resistor R10, and resistor R11. The output of the first winding of the secondary side of the power transformer T1 in the power conversion circuit 3 is connected to the rectifier and filter output circuit 4. After rectification and filtering, it is connected to the charging output interface of the charger. Diode D3, capacitor C6 and resistor R14, and capacitor C7 constitute the rectifier and filter circuit. Common mode inductor NF1 and resistor R28 constitute the final stage filter circuit. The positive terminal of the second winding of the secondary side of the power transformer T1 in the power conversion circuit 3 supplies power to the chip U2 of the constant current lamp-turning circuit 5, and is connected to the VCC pin of the chip U2. The chip U2 is a constant voltage and constant current dual-loop control chip with a charging indicator LED1 color conversion function, and the model of the chip U2 is ME4312. The constant current lamp-turning circuit 5 is connected to the rectifier and filter output circuit 4 to form the control loop input of the chip U2. One path of the VSENSE pin of the chip U2 is grounded through resistors R23 and R27 in sequence, and the other path is connected to the positive terminal of the rectifier and filter output circuit 4 through capacitor C11, resistor R19, and R18 in sequence. The common terminal of capacitor C11 and resistor R19 is grounded. Pin 3 of the chip U2 is grounded, and the control output VOUT of the chip U2 is connected to the feedback stabilizer. One input terminal of the optocoupler PC1A in the voltage circuit 6 is connected to the other input terminal of the optocoupler PC1A, which is grounded through resistor R15 and capacitor C8. The output terminal PC1B of the optocoupler PC1 is connected to the feedback input terminal FB of the PWM control chip U1 in the PWM main control IC circuit 7. One path of the VCTRL pin of the chip U2 is connected to the positive terminal of the rectifier filter output circuit 4 through resistor R18, and the other path is connected to the common terminal of the control output VOUT pin of the chip U2 and the input terminal of the optocoupler PC1A through resistor R17 and capacitor C9. The charging indicator LED1 is a dual indicator light, which is connected to pins 1 and 8 of the chip U2 respectively, corresponding to the red and green control pins respectively. The ICTRL pin of the chip U2 is grounded through a parallel circuit composed of resistor R21 and capacitor C10.

[0017] The above embodiments are merely preferred embodiments of the present utility model and are only used to explain the present utility model, not to limit the present utility model. Any changes, substitutions, combinations, simplifications, modifications, etc., made by those skilled in the art without departing from the spirit and principle of the present utility model shall be considered equivalent substitutions and shall be included within the protection scope of the present utility model.

Claims

1. A miniaturized wall-mounted 18W lithium battery charger, characterized in that: Its internal circuitry includes an AC input circuit, an EMI rectifier and filter circuit, a power conversion circuit, a rectifier and filter output circuit, a constant current lamp-turning circuit, a feedback voltage regulator circuit, and a PWM main control IC circuit. The output terminal of the AC input circuit is connected to the input terminal of the rectifier bridge BD1 of the EMI rectifier and filter circuit. A filter circuit composed of filter capacitors C1 and C2 and inductors L1 and L2 is connected between the output terminals of the rectifier bridge BD1. The positive terminal of the output terminal of the EMI rectifier and filter circuit is connected to the positive terminal of the first winding of the primary side of the power transformer T1 in the power conversion circuit. The negative terminal of the first winding of the primary side is connected to the output control terminal of the PWM control chip U1 in the PWM main control IC circuit. The second winding of the primary side of the power transformer T1 provides operating power to the chip U1. Voltage; the output of the first winding of the secondary side of the power transformer T1 in the power conversion circuit is connected to the charging output interface of the charger after rectification and filtering by the rectifier and filter output circuit; the positive terminal of the second winding of the secondary side of the power transformer T1 in the power conversion circuit supplies power to the chip U2 of the constant current lamp switching circuit. The chip U2 is a constant voltage and constant current dual-loop control chip with color conversion function of charging indicator LED1; the constant current lamp switching circuit is connected to the rectifier and filter output circuit to form the control loop input of chip U2, the control output of chip U2 is connected to the input terminal of the optocoupler PC1 of the feedback voltage regulator circuit, and the output terminal of the optocoupler PC1 is connected to the feedback input terminal of the PWM control chip U1 of the PWM main control IC circuit.

2. The miniaturized wall-mounted 18W lithium battery power charger according to claim 1, characterized in that: The AC input circuit is equipped with an overcurrent protection fuse F1 and a lightning protection varistor ZR1.

3. The miniaturized wall-mounted 18W lithium battery power charger according to claim 1, characterized in that: The PWM control chip U1 is model CJW3561DD.

4. The miniaturized wall-mounted 18W lithium battery power charger according to claim 1, characterized in that: The chip U2 is model ME4312.

5. The miniaturized wall-mounted 18W lithium battery power charger according to claim 1, characterized in that: The charging indicator LED1 is a dual-channel indicator, which is connected to two different colored control pins of chip U2.

Images