Power supply charger capable of automatically checking output voltage

Abstract

The utility model discloses a power supply charger capable of automatically checking output voltage. The internal circuit comprises a commercial power input and anti-lightning stroke circuit, a bridge type rectification filter circuit, a flyback converter circuit, a power transformer circuit, a secondary rectification circuit, an output voltage test circuit, an anti-reverse connection circuit, a flyback IC control circuit, an intelligent MCU verification circuit and a fan and voltage stabilization drive circuit. According to the power supply charger with the function of automatically checking the output voltage, the output voltage checking circuit is designed, and the output voltage is checked through an internal program of the intelligent MCU checking circuit, so that the voltage output of the power supply charger is ensured to be within a stable range; and by adopting the flyback conversion circuit and the flyback power transformer, the internal circuit of the charger has the advantage of simple topology.

Description

Technical Field

[0001] The utility model belongs to the technical field of power chargers, and in particular relates to a power charger with automatic output voltage verification. Background Art

[0002] Some electrical appliances have special requirements for the output of power chargers, such as power chargers used for physical therapy electrotherapy products. Existing power chargers generally do not calibrate the output voltage. If the internal circuit failure of the power charger causes unstable voltage output, the working state of the electrotherapy product will deviate from the normal working state, causing unexpected movements during patient treatment, such as muscle damage or nerve damage, and other bad treatment experiences. Therefore, it is necessary to design a power charger with automatic output voltage calibration. Utility Model Content

[0003] The utility model aims to solve the above problems and provide a power charger with automatic output voltage verification, which can automatically verify the output voltage of the power charger and ensure that the power charger is in a stable output range.

[0004] The utility model is realized by the following technical solutions:

[0005] A power charger with automatic output voltage verification, whose internal circuit includes a mains input and lightning protection circuit, a bridge rectifier filter circuit, a flyback converter circuit, a power transformer circuit, a secondary rectifier circuit, an output voltage verification circuit, an anti-reverse connection circuit, a flyback IC control circuit, an intelligent MCU verification circuit, and a fan and voltage stabilization drive circuit;

[0006] The output end of the mains input and lightning protection circuit is connected to the input end of the rectifier bridge BD1 of the bridge rectifier filter circuit, and the output end of the rectifier bridge BD1 is connected to a parallel circuit composed of filter capacitors C1 and C2. The positive electrode of the output end of the rectifier bridge BD1 of the bridge rectifier filter circuit is connected to the positive end of the primary first winding of the flyback power transformer T1 of the power transformer circuit, and the negative end of the primary first winding is connected to the flyback converter circuit containing the MOS tube Q1. The negative end of the primary first winding is connected to the drain of the MOS tube Q1, and the source of the MOS tube Q1 is connected through the resistor R1. 7 is connected to PGND; the gate of the MOS tube Q1 is connected to the flyback IC control circuit including the chip U1; the chip U1 model is OB5282, the PRT pin of the chip U1 is connected to PGND through the series-connected diode D1, resistor R2 and thermistor RT2, the CS pin is connected to the source of the MOS tube Q1 through the resistor R27, the GND pin is connected to PGND, the GATE pin is connected to the gate of the MOS tube Q1 through the resistors R6 and R7 in sequence, and the VDD pin is connected to the primary second winding of the flyback power transformer T1 of the power transformer circuit through the circuit To obtain the working voltage, the source of the MOS tube Q1 is connected to the positive output terminal of the rectifier bridge BD1 through the diode D2 and the resistors R8, R11, and R14; the two ends of the secondary first winding of the flyback power transformer T1 are connected to the output voltage detection circuit through the secondary rectifier circuit; the output voltage detection circuit includes a transistor Q8, the emitter of the transistor Q8 is connected to the positive output terminal V+ of the output voltage detection circuit through the resistor R58, and the collector of the transistor Q8 is grounded through the resistors R42 and R41 in sequence; the base of the transistor Q8 is connected to the positive output terminal V+ of the output voltage detection circuit through the resistor R4 7 is connected to the emitter of the transistor Q8, and is connected to the negative output terminal V- of the charger through a resistor R46; the connection point of the resistors R42 and R41 is connected to the sampling terminal ADC0 through a resistor R39, and the sampling terminal ADC0 is grounded through a capacitor C15; the anti-reverse connection circuit includes a thyristor Q5 for preventing current backflow, the control electrode of the thyristor Q5 is connected to the PA4 pin of the chip U2 of the intelligent MCU verification circuit through a resistor R45, the cathode of the thyristor Q5 is grounded through a resistor R43, and the anode of the thyristor Q5 is connected to the negative output terminal V- of the charger;

[0007] The model of chip U2 of the intelligent MCU verification circuit is HT45F5Q-2A; the OPAE output end of chip U2 is also connected to the input part PC1A of the optocoupler PC1, and the output part PC1B of the optocoupler PC1 is connected to the feedback input FB end of chip U1; the secondary second winding of the flyback power transformer T1 of the power transformer circuit is connected to the fan and voltage stabilizing drive circuit, and the voltage stabilizing drive circuit of the fan and voltage stabilizing drive circuit provides the working voltage for chip U2, and the +5V output by the voltage stabilizing drive circuit is connected to the VDD pin of chip U2; the fan voltage input control of the fan and voltage stabilizing drive circuit is provided with a control signal by the PA7 pin of chip U2; the OPA1N pin of chip U2 is connected to the positive output end of the charger through resistor R50.

[0008] Furthermore, the AC input and lightning protection circuit is provided with a fuse F1 for overcurrent protection, a varistor ZR1 for lightning protection, and a thermistor RT1 for overtemperature protection.

[0009] Furthermore, the chip U2 of the intelligent MCU verification circuit is also connected to a power device or ambient temperature over-temperature protection and detection circuit, and the over-temperature protection and detection circuit includes thermistors RT3 and RT4. The detection signal terminals NTC3 and NTC4 derived from the thermistors RT3 and RT4 are respectively connected to the PB1 input pin and PB2 input pin of the chip U2.

[0010] Furthermore, the intelligent MCU verification circuit is also connected to the LED charging indicator light LED1, and the LED1 is a dual-way indicator light, one way is connected between the PA3 pin of the chip U2 and the +5V of the fan and the voltage-stabilizing drive circuit, and the other way is connected between the PA2 pin of the chip U2 and the +5V of the fan and the voltage-stabilizing drive circuit.

[0011] The beneficial effects of the utility model are: 1. The power charger with automatic output voltage verification of the utility model is designed with an output voltage verification circuit, and verifies the output voltage through the internal program of the intelligent MCU verification circuit, thereby ensuring that the voltage output of the power charger is within a stable range; 2. The use of a flyback conversion circuit and a flyback power transformer makes the internal circuit of the charger have the advantage of simple topology. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a principle block diagram of the utility model.

[0013] Figure 2 This is a circuit schematic diagram of the utility model.

[0014] In the figure, 1. AC power input and anti-lightning circuit, 2. Bridge rectifier filter circuit, 3. Flyback converter circuit, 4. Power transformer circuit, 5. Secondary rectifier circuit, 6. Output voltage detection circuit, 7. Anti-reverse connection circuit, 8. Flyback IC control circuit, 9. Intelligent MCU verification circuit, 10. Fan and voltage stabilization drive circuit. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with specific examples and accompanying drawings.

[0016] like Figure 1 , Figure 2 As shown, a power charger with automatic output voltage verification, whose internal circuit includes a mains input and lightning protection circuit 1, a bridge rectifier filter circuit 2, a flyback converter circuit 3, a power transformer circuit 4, a secondary rectifier circuit 5, an output voltage verification circuit 6, an anti-reverse connection circuit 7, a flyback IC control circuit 8, an intelligent MCU verification circuit 9 and a fan and voltage stabilization drive circuit 10;

[0017] The mains input and lightning protection circuit 1 is provided with an overcurrent protection fuse F1, an anti-lightning varistor ZR1 and an over-temperature protection thermistor RT1. The output end of the mains input and lightning protection circuit 1 is connected to the input end of the rectifier bridge BD1 of the bridge rectifier filter circuit 2, and a parallel circuit composed of filter capacitors C1 and C2 is connected between the output ends of the rectifier bridge BD1. The positive pole of the output end of the rectifier bridge BD1 of the bridge rectifier filter circuit 2 is connected to the positive end of the primary first winding of the flyback power transformer T1 of the power transformer circuit 4, and the negative end of the primary first winding is connected to the flyback converter circuit 3 containing the MOS tube Q1, and the negative end of the primary first winding is connected to the drain of the MOS tube Q1, and the source of the MOS tube Q1 is connected to PGND through the resistor R17. The gate of the MOS tube Q1 is connected to the flyback IC control circuit 8 including the chip U1; the chip U1 model is OB5282, the 1st pin (PRT pin) of the chip U1 is connected to PGND through the series-connected diode D1, resistor R2 and thermistor RT2, the 3rd pin (CS pin) is connected to the source of the MOS tube Q1 through the resistor R27, the 4th pin (GND pin) is connected to the PGND, the 5th pin (GATE pin) is connected to the gate of the MOS tube Q1 through the resistors R6 and R7 in sequence, and the 6th pin (VDD pin) is connected to the primary side of the flyback power transformer T1 of the power transformer circuit 4 through the circuit. The winding obtains the working voltage, the source of the MOS tube Q1 is connected to the positive output terminal of the rectifier bridge BD1 through the diode D2 and the resistors R8, R11, and R14; the two ends of the secondary first winding of the flyback power transformer T1 are connected to the output voltage detection circuit 6 through the secondary rectifier circuit 5; the output voltage detection circuit 6 includes a transistor Q8, the emitter of the transistor Q8 is connected to the positive output terminal V+ of the output voltage detection circuit 6 through the resistor R58, and the collector of the transistor Q8 is connected to the ground (GND) through the resistors R42 and R41 in turn; the base of the transistor Q8 is connected to the positive output terminal V+ of the output voltage detection circuit 6 through the resistor R4 7 is connected to the emitter of the transistor Q8, and is connected to the negative output terminal V- of the charger through a resistor R46; the connection point of the resistors R42 and R41 is connected to the sampling terminal ADC0 through a resistor R39, and the sampling terminal ADC0 is grounded (GND) through a capacitor C15; the anti-reverse connection circuit 7 includes a thyristor Q5 for preventing current backflow, the control electrode of the thyristor Q5 is connected to the PA4 pin of the chip U2 of the intelligent MCU verification circuit 9 through a resistor R45, the cathode of the thyristor Q5 is grounded (GND) through a resistor R43, and the anode of the thyristor Q5 is connected to the negative output terminal V- of the charger;

[0018] The model of the chip U2 of the intelligent MCU verification circuit 9 is HT45F5Q-2A; the OPAE output end of the chip U2 is also connected to the input part PC1A of the optocoupler PC1, and the output part PC1B of the optocoupler PC1 is connected to the feedback input FB end (pin 2) of the chip U1; the secondary second winding of the flyback power transformer T1 of the power transformer circuit 4 is connected to the fan and voltage stabilizing drive circuit 10, and the voltage stabilizing drive circuit of the fan and voltage stabilizing drive circuit 10 provides the working voltage for the chip U2, and the +5V output by the voltage stabilizing drive circuit is connected to the VDD pin of the chip U2. The fan voltage input control of the fan and voltage stabilizing drive circuit 10 provides a control signal by the PA7 pin of the chip U2. The OPA1N pin of the chip U2 is connected to the positive output end of the charger through the resistor R50.

[0019] The chip U2 of the intelligent MCU verification circuit 9 is also connected to a power device or ambient temperature over-temperature protection and detection circuit, and the over-temperature protection and detection circuit includes thermistors RT3 and RT4. The detection signal terminals NTC3 and NTC4 derived from the thermistors RT3 and RT4 are respectively connected to the PB1 input pin and PB2 input pin of the chip U2.

[0020] The intelligent MCU verification circuit 9 is also connected to the LED charging indicator light LED1, and the LED1 is a dual-way indicator light, one way is connected between the PA3 pin of the chip U2 and the +5V of the fan and the voltage-stabilizing drive circuit 10, and the other way is connected between the PA2 pin of the chip U2 and the +5V of the fan and the voltage-stabilizing drive circuit 10.

[0021] Y capacitors, YC1 and YC2, are connected in series between the PGND and GND.

[0022] The above embodiments are only preferred implementation modes of the present invention and are only used to explain the present invention rather than to limit the present invention. Any changes, substitutions, combinations, simplifications, modifications, etc. made by those skilled in the art without departing from the spirit and principles of the present invention shall be considered as equivalent replacement modes and shall be included in the protection scope of the present invention.

Claims

1. A power charger with automatic output voltage verification, Features: Its internal circuit includes AC input and lightning protection circuit, bridge rectifier filter circuit, flyback converter circuit, power transformer circuit, secondary rectifier circuit, output voltage test circuit, anti-reverse connection circuit, flyback IC control circuit, intelligent MCU test circuit and fan and voltage stabilization drive circuit; The output end of the mains input and lightning protection circuit is connected to the input end of the rectifier bridge BD1 of the bridge rectifier filter circuit, and the output end of the rectifier bridge BD1 is connected to a parallel circuit composed of filter capacitors C1 and C2. The positive electrode of the output end of the rectifier bridge BD1 of the bridge rectifier filter circuit is connected to the positive end of the primary first winding of the flyback power transformer T1 of the power transformer circuit, and the negative end of the primary first winding is connected to the flyback converter circuit containing the MOS tube Q1. The negative end of the primary first winding is connected to the drain of the MOS tube Q1, and the source of the MOS tube Q1 is connected through the resistor R1. 7 is connected to PGND; the gate of the MOS tube Q1 is connected to the flyback IC control circuit including the chip U1; the chip U1 model is OB5282, the PRT pin of the chip U1 is connected to PGND through the series-connected diode D1, resistor R2 and thermistor RT2, the CS pin is connected to the source of the MOS tube Q1 through the resistor R27, the GND pin is connected to PGND, the GATE pin is connected to the gate of the MOS tube Q1 through the resistors R6 and R7 in sequence, and the VDD pin is connected to the primary second winding of the flyback power transformer T1 of the power transformer circuit through the circuit To obtain the working voltage, the source of the MOS tube Q1 is connected to the positive output terminal of the rectifier bridge BD1 through the diode D2 and the resistors R8, R11, and R14; the two ends of the secondary first winding of the flyback power transformer T1 are connected to the output voltage detection circuit through the secondary rectifier circuit; the output voltage detection circuit includes a transistor Q8, the emitter of the transistor Q8 is connected to the positive output terminal V+ of the output voltage detection circuit through the resistor R58, and the collector of the transistor Q8 is grounded through the resistors R42 and R41 in sequence; the base of the transistor Q8 is connected to the positive output terminal V+ of the output voltage detection circuit through the resistor R4 7 is connected to the emitter of the transistor Q8, and is connected to the negative output terminal V- of the charger through a resistor R46; the connection point of the resistors R42 and R41 is connected to the sampling terminal ADC0 through a resistor R39, and the sampling terminal ADC0 is grounded through a capacitor C15; the anti-reverse connection circuit includes a thyristor Q5 for preventing current backflow, the control electrode of the thyristor Q5 is connected to the PA4 pin of the chip U2 of the intelligent MCU verification circuit through a resistor R45, the cathode of the thyristor Q5 is grounded through a resistor R43, and the anode of the thyristor Q5 is connected to the negative output terminal V- of the charger; The model of chip U2 of the intelligent MCU verification circuit is HT45F5Q-2A; the OPAE output end of chip U2 is also connected to the input part PC1A of the optocoupler PC1, and the output part PC1B of the optocoupler PC1 is connected to the feedback input FB end of chip U1; the secondary second winding of the flyback power transformer T1 of the power transformer circuit is connected to the fan and voltage stabilizing drive circuit, and the voltage stabilizing drive circuit of the fan and voltage stabilizing drive circuit provides the working voltage for chip U2, and the +5V output by the voltage stabilizing drive circuit is connected to the VDD pin of chip U2; the fan voltage input control of the fan and voltage stabilizing drive circuit is provided with a control signal by the PA7 pin of chip U2; the OPA1N pin of chip U2 is connected to the positive output end of the charger through resistor R50.

2. The power charger with automatic output voltage verification according to claim 1, Features: The mains input and lightning protection circuit is provided with a fuse F1 for overcurrent protection, a varistor ZR1 for lightning protection, and a thermistor RT1 for overtemperature protection.

3. The power charger with automatic output voltage verification according to claim 1, Features: The chip U2 of the intelligent MCU verification circuit is also connected to a power device or ambient temperature over-temperature protection and detection circuit, and the over-temperature protection and detection circuit includes thermistors RT3 and RT4. The detection signal terminals NTC3 and NTC4 derived from the thermistors RT3 and RT4 are respectively connected to the PB1 input pin and PB2 input pin of the chip U2.

4. The power charger with automatic output voltage verification according to claim 1, Features: The intelligent MCU verification circuit is also connected to the LED charging indicator LED1, and the LED1 is a dual-way indicator light, one way is connected between the PA3 pin of the chip U2 and the +5V of the fan and the voltage-stabilizing drive circuit, and the other way is connected between the PA2 pin of the chip U2 and the +5V of the fan and the voltage-stabilizing drive circuit.

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