Low-power-consumption anti-surge current control circuit

Abstract

The utility model relates to the technical field of switching power supplies, and discloses a low-power-consumption anti-surge current control circuit, which comprises an alternating current power supply circuit, a rectification filter circuit, a transformation circuit, an anti-surge circuit, an output circuit and a pulse circuit, the rectification filter circuit is also connected with the transformation circuit. The output end of the transformation circuit is connected with the output circuit, the pulse circuit and the anti-surge circuit. The anti-surge circuit comprises a silicon controlled rectifier Q2, a resistor R13 and a resistor R14, the alternating current power supply circuit comprises a resistor FR1, the resistor FR1 is connected to a zero line of an alternating current power supply in series, the silicon controlled rectifier Q2 is connected with the resistor FR1 in parallel, a control electrode of the silicon controlled rectifier Q2 is connected with the power supply output ends of the resistor R13 and the resistor R14 in series, and the input ends of the resistor R13 and the resistor R14 in series are connected with the voltage transformation circuit. The switching power supply circuit realizes a low-power-consumption anti-surge switching power supply.

Description

Technical Field

[0001] The utility model relates to the technical field of switch power supplies, in particular to a low-power consumption surge current protection control circuit. Background Art

[0002] A switching power supply, also known as an exchange power supply or a switching converter, is a high-frequency power conversion device and a type of power supply. Its function is to convert a voltage level into the voltage or current required by the user through different forms of architecture. The input of a switching power supply is mostly AC power (such as mains) or DC power, and the output is mostly a device that requires DC power, such as a personal computer, and the switching power supply performs the voltage and current conversion between the two.

[0003] At present, in the commonly used switching power supply, the input surge current suppression measure is to connect a negative temperature coefficient thermistor in series between the neutral line and the rectifier bridge. The resistance of the negative temperature coefficient thermistor will decrease as the temperature rises. When the switching power supply is turned on, the thermistor is at room temperature and has a relatively high resistance, which can effectively limit the input surge current; after the power supply is started, the resistance of the thermistor decreases as the body temperature rises, which can reduce the power loss during the normal operation of the switching power supply. However, if the input power supply is suddenly cut off during operation, and the power supply is restarted before the temperature of the thermistor drops, the resistance of the thermistor is in a low state at this time, and the input surge current cannot be effectively suppressed, and the surge current will exceed the specification. In addition, although the resistance of the thermistor will decrease as the temperature rises, there will still be a certain resistance, which will cause the efficiency of the switching power supply to decrease; in addition, the output voltage and current of the existing switching power supply are unstable, which affects the power supply requirements of subsequent circuit components.

[0004] Therefore, in view of the above problems, the existing switching power supply method needs to be further improved. Utility Model Content

[0005] The purpose of the utility model is to overcome the problems of surge phenomenon, high power consumption and unstable output voltage and current of the existing switching power supply. Through the rational design of the switching power supply circuit, the surge current control circuit composed of AC power supply circuit, rectifier filter circuit, transformer circuit, surge protection circuit, output circuit and pulse circuit can be used to effectively suppress the surge phenomenon of the switching power supply, reduce power consumption and stabilize the output voltage and current.

[0006] The technical solution of the utility model is as follows:

[0007] A low-power surge current control circuit, the surge current control circuit comprising: an AC power supply circuit, a rectifier and filter circuit, a transformer circuit, a surge protection circuit, an output circuit and a pulse circuit, the power input end of the AC power supply circuit is connected to an external AC power supply, the power output end of the AC power supply circuit is connected to the input end of the rectifier and filter circuit, the output end of the rectifier and filter circuit is connected to the input end of the transformer circuit, and the output end of the transformer circuit is respectively connected to the input end of the output circuit, the input end of the pulse circuit and the input end of the surge protection circuit;

[0008] Among them, the surge protection circuit includes a thyristor Q2, a resistor R13 and a resistor R14, the AC power supply circuit includes a resistor FR1, the resistor FR1 is connected in series to the neutral line of the AC power supply, the thyristor Q2 is connected in parallel with the resistor FR1, and the first anode of the thyristor Q2 is connected to the power input end, the second anode of the thyristor Q2 is connected to the neutral line, the control electrode of the thyristor Q2 is connected to the power output end of the series resistor R13 and the resistor R14, and the power input end of the series resistor R13 and the resistor R14 is connected to the output end of the transformer circuit.

[0009] Furthermore, the AC power supply circuit also includes a fuse F1, a varistor VDR1, a capacitor CX1, a resistor R1a, a resistor R1c, a resistor R1b, a resistor R1d and a mutual inductance LF1. One end of the fuse F1 is connected to the live wire, and the other end of the fuse F1 is connected in parallel to one end of the varistor VDR1, one end of the capacitor CX1, one end of the resistor R1a, one end of the resistor R1c and a "1" terminal of the mutual inductance LF1. One end of the resistor FR1 is connected in parallel to the neutral line, the other end of the varistor VDR1 and the second anode of the thyristor Q2. The other end of the resistor FR1 is connected in parallel to the other end of the capacitor CX1, the first anode of the thyristor Q2, the other end of the resistor R1b, the other end of the resistor R1d and the "2" terminal of the mutual inductance LF1. The other end of the resistor R1a and the other end of the resistor R1c are connected to one end of the resistor R1b and one end of the resistor R1d. The "3" terminal and the "4" terminal of the mutual inductance LF1 serve as the power output end of the AC power supply circuit.

[0010] Furthermore, the rectifier and filter circuit includes a bridge rectifier and filter circuit and an RC filter circuit, the input end of the bridge rectifier and filter circuit is connected to the power output end of the AC power supply circuit, the output end of the bridge rectifier and filter circuit is connected to the input end of the RC filter circuit, and the output end of the RC filter circuit is connected to the input end of the transformer circuit.

[0011] Furthermore, the bridge rectifier filter circuit includes a bridge DB1, a capacitor C1a and a capacitor C1b, the "2" terminal and the "3" terminal of the bridge DB1 are respectively connected to the power output end of the AC power supply circuit, the "4" terminal of the bridge DB1 is grounded, the "1" terminal of the bridge DB1 is connected in parallel to one end of the capacitor C1a, one end of the capacitor C1b and the input end of the RC filter circuit, and the other end of the capacitor C1a and the other end of the capacitor C1b are grounded.

[0012] Further, the RC filter circuit includes a resistor R4a, a resistor R4b, a resistor R4c, a resistor R4d, a resistor R5a, a resistor R5b, a resistor R5c and a capacitor C1a, one end of the resistor R4a, one end of the resistor R4b, one end of the resistor R4c, one end of the resistor R4d and one end of the capacitor C1a are connected to the output end of the bridge rectifier filter circuit and the input end of the transformer circuit, the other end of the resistor R4a, the other end of the resistor R4b, the other end of the resistor R4c, the other end of the resistor R4d and the other end of the capacitor C1a are connected to one end of the resistor R5a, one end of the resistor R5b and one end of the resistor R5c, and the other end of the resistor R5a, the other end of the resistor R5b and the other end of the resistor R5c are connected to the control end of the pulse circuit.

[0013] Furthermore, the transformer circuit includes a transformer TR1, wherein the "1" terminal and the "2" terminal of the transformer TR1 are respectively connected to the output end of the rectifier and filter circuit, the "3" terminal and the "4" terminal of the transformer TR1 are respectively connected to the input end of the output circuit, and the "5" terminal and the "6" terminal of the transformer TR1 are respectively connected to the input end of the pulse circuit.

[0014] Furthermore, the output circuit includes a DC output circuit and a voltage stabilizing circuit, the input end of the DC output circuit is connected to the output end of the voltage transformation circuit, and the output end of the DC output circuit is connected in parallel to the output port and the input end of the voltage stabilizing circuit.

[0015] Furthermore, the DC output circuit includes a diode D6, a resistor R19a, a resistor R19b, a resistor R19c, a resistor R26, a resistor R25, a capacitor C9, a capacitor CD4, a capacitor CD5, a capacitor C11, a voltage regulator DZ3 and an LED1, the positive electrode of the diode D6 and one end of the resistor R19a, one end of the resistor R19b and one end of the resistor R19c are connected to the positive terminal of the output end of the transformer circuit, and the other end of the resistor R19a, the other end of the resistor R19b and the other end of the resistor R19c are connected to the positive terminal of the output end of the transformer circuit. One end is connected to one end of capacitor C9, the cathode of the diode D6 and the other end of the capacitor C9 are connected to one end of the capacitor CD4, one end of the capacitor CD5, one end of the capacitor C11, the cathode of the voltage regulator DZ3, one end of the resistor R25 and one end of the resistor R26, the other end of the resistor R26 is connected to the anode of LED1, and the cathode of the output end of the transformer circuit is grounded together with the other end of the resistor R25, the other end of the capacitor CD4, the other end of the capacitor CD5, the other end of the capacitor C11, the anode of the voltage regulator DZ3 and the cathode of LED1.

[0016] Furthermore, the voltage stabilizing circuit includes a resistor R20, a resistor R21, a resistor R22, a resistor R23, a resistor R24a, a resistor R24b, an optocoupler PC1A, a voltage regulator IC2 and a capacitor C10, one end of the resistor R20 is connected to the positive electrode of the DC power supply, the other end of the resistor R20 is connected in parallel to the positive electrode of the optocoupler PC1A and one end of the resistor R21, the negative electrode of the optocoupler PC1A and the other end of the resistor R21 are commonly connected to one end of the capacitor C10 and a "2" terminal of the voltage regulator IC2, one end of the resistor R23 is connected to the output port, the other end of the resistor R23 is connected in parallel to one end of the resistor R22, a "1" terminal of the voltage regulator IC2, one end of the resistor R24a and one end of the resistor R24b, the other end of the resistor R22 is connected to the other end of the capacitor C10, and the other end of the resistor R24a and the other end of the resistor R24b are commonly grounded with a "3" terminal of the voltage regulator IC2.

[0017] Furthermore, the pulse circuit includes a resistor R2a, a resistor R2b, a diode D2, a diode D3, an inductor L1, a capacitor CD2, a capacitor CD3, a resistor R7, a diode D4, an NMOS tube Q1, a capacitor C4b, a resistor R6a, a resistor R6b, a resistor R8, a capacitor C5, a resistor R10a, a resistor R9a, a resistor R9b, a resistor R9c, a resistor R9d, a capacitor C3, a capacitor CD3, a chip IC1, an inductor L2, a capacitor C6, an inductor L3, a voltage regulator tube DZ2 and an optocoupler PC1B, and the positive terminal of the output end of the transformer circuit is connected to one end of the inductor L1, and the inductor L1 The other end is connected to the positive electrode of the diode D2, the negative electrode of the diode D2 is connected in parallel to the positive electrode of the diode D3, one end of the capacitor CD2 and the input end of the surge protection circuit, the other end of the capacitor CD2 is grounded, the negative electrode of the diode D3 is connected in parallel to the series resistor R2a and one end of the resistor R2b, one end of the capacitor CD3 and the chip IC1 "5" terminal, the other end of the series resistor R2a and the resistor R2b is connected to the AC power supply circuit, the other end of the capacitor CD3 is grounded, the chip IC1 "1" terminal is grounded, the chip IC1 "2" terminal is connected to one end of the inductor L2, and the other end of the inductor L2 is connected in parallel to one end of the capacitor C6 , the optocoupler PC1B "4" terminal and the negative electrode of the voltage regulator tube DZ2, the optocoupler PC1B "3" terminal is connected to one end of the inductor L3, the positive electrode of the voltage regulator tube DZ2, the other end of the capacitor C6 and the other end of the inductor L3 are grounded, the chip IC1 "4" terminal is connected in parallel to one end of the resistor R10a and one end of the capacitor C3, the other end of the resistor R10a is connected in parallel to one end of the resistor R9a, one end of the resistor R9b, one end of the resistor R9c and one end of the resistor R9d, the other end of the capacitor C3, the other end of the resistor R9a, the other end of the resistor R9b, the other end of the resistor R9c and the other end of the resistor R9d are grounded, The "6" terminal of the chip IC1 is connected to one end of the resistor R6a, the other end of the resistor R6a is connected in parallel to one end of the resistor R6b and one end of the resistor R7, the other end of the resistor R7 is connected to the cathode of the diode D4, the other end of the resistor R6b is connected in parallel to one end of the capacitor C5, one end of the resistor R8, the anode of the diode D4 and the gate of the NMOS tube Q1, the other end of the capacitor C5 and the other end of the resistor R8 are grounded, the source of the NMOS tube Q1 is connected in parallel to one end of the capacitor C4b and the other end of the resistor R10a, and the other end of the capacitor C4b is connected in parallel to the drain of the NMOS tube Q1 and the input end of the transformer circuit.

[0018] Furthermore, the capacitor CD2, the capacitor CD3, the capacitor CD4, and the capacitor CD5 are all variable capacitors.

[0019] Furthermore, the chip IC1 is selected as model OB2281AMP.

[0020] Furthermore, the chip IC2 is selected as model TL431.

[0021] Beneficial Effects

[0022] The utility model can realize a low-power and surge-proof switching power supply by rationally designing the switching power supply circuit, adopting an AC power supply circuit, a rectifier filter circuit, a voltage transformer circuit, a surge protection circuit, an output circuit and a pulse circuit, wherein a fixed resistance resistor is used to replace the thermistor, and the resistor is connected in parallel with a bidirectional thyristor. When the switching power supply is turned on, the thyristor Q2 is cut off and does not conduct, and the current flows through the resistor FR1, and FR1 plays a role in suppressing the input surge current. When the switching power supply starts to work, at this time, there will be a current passing through the resistors R13 and R14 to give a trigger signal to the trigger pole of the thyristor Q2, so that the thyristor is turned on. After the thyristor is turned on, the input current will flow through the thyristor, and the current flowing through the resistor is extremely low, and the resistor is almost in a state of disconnection, which greatly reduces the power loss of the switching power supply; there are also transformers and pre-order rectification, subsequent voltage stabilization circuits, chip feedback signal processing, etc. that cooperate with it, which can realize a more stable output voltage to ensure the normal power supply of the subsequent electronic circuits and extend the service life of electronic components. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The utility model is a structural schematic diagram of a low-power consumption surge current protection control circuit.

[0024] Figure 2 The utility model is a schematic diagram of the principle of a low-power consumption surge current protection control circuit.

[0025] Figure numbers: 01, AC power supply circuit; 02, rectifier and filter circuit; 03, transformer circuit; 04, pulse circuit; 05, surge protection circuit; 06, output circuit. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] See also Figure 1-Figure 2As shown, the utility model provides a low-power anti-surge current control circuit, which includes: an AC power supply circuit 01, a rectifier and filter circuit 02, a transformer circuit 03, an anti-surge circuit 05, an output circuit 06 and a pulse circuit 04, wherein the power input end of the AC power supply circuit 01 is connected to an external AC power supply, the power output end of the AC power supply circuit 01 is connected to the input end of the rectifier and filter circuit 02, the output end of the rectifier and filter circuit 02 is connected to the input end of the transformer circuit, and the output end of the transformer circuit is respectively connected to the input end of the output circuit 06, the input end of the pulse circuit 04 and the input end of the anti-surge circuit 05;

[0028] Among them, the rectifier and filter circuit 02 includes a bridge rectifier and filter circuit 02 and an RC filter circuit, the input end of the bridge rectifier and filter circuit 02 is connected to the power output end of the AC power supply circuit 01, the output end of the bridge rectifier and filter circuit 02 is connected to the input end of the RC filter circuit, and the output end of the RC filter circuit is connected to the input end of the transformer circuit; the output circuit 06 includes a DC output circuit 06 and a voltage stabilizing circuit, the input end of the DC output circuit 06 is connected to the output end of the transformer circuit, and the output end of the DC output circuit 06 is connected in parallel to the output port and the input end of the voltage stabilizing circuit;

[0029] Wherein, the surge protection circuit 05 includes a thyristor Q2, a resistor R13 and a resistor R14, and the AC power supply circuit 01 includes a resistor FR1, the resistor FR1 is connected in series to the neutral line of the AC power supply, the thyristor Q2 is connected in parallel with the resistor FR1, and the first anode of the thyristor Q2 is connected to the power input end, the second anode of the thyristor Q2 is connected to the neutral line, the control electrode of the thyristor Q2 is connected to the power output end of the series resistor R13 and the resistor R14, and the power input end of the series resistor R13 and the resistor R14 is connected to the output end of the transformer circuit;

[0030] Specifically, the surge protection circuit 05 includes a thyristor Q2, a resistor R13 and a resistor R14, the AC power supply circuit 01 includes a resistor FR1, the AC power supply circuit 01 also includes a fuse F1, a varistor VDR1, a capacitor CX1, a resistor R1a, a resistor R1c, a resistor R1b, a resistor R1d and a mutual inductance LF1, the bridge rectifier filter circuit 02 includes a bridge DB1, a capacitor C1a and a capacitor C1b, the RC filter circuit includes a resistor R4a, a resistor R4b, a resistor R4c, a resistor R4d, a resistor R5a, a resistor R5b, a resistor R5c and a capacitor C1a, the transformer circuit 03 includes a transformer TR1, and the DC output circuit 06 includes a diode D6, a resistor R19a, a resistor R19b, a resistor R19c, a resistor R26, a resistor R25, a capacitor C9, Capacitor CD4, capacitor CD5, capacitor C11, voltage regulator DZ3 and LED1, the voltage regulator circuit includes resistor R20, resistor R21, resistor R22, resistor R23, resistor R24a, resistor R24b, optocoupler PC1A, voltage regulator IC2 and capacitor C10, pulse circuit 04 includes resistor R2a, resistor R2b, diode D2, diode D3, inductor L1, capacitor CD2, capacitor CD3, resistor R7, diode D4, NMOS tube Q1, capacitor C4b, resistor R6a, resistor R6b, resistor R8, capacitor C5, resistor R10a, resistor R9a, resistor R9b, resistor R9c, resistor R9d, capacitor C3, capacitor CD3, chip IC1, inductor L2, capacitor C6, inductor L3, voltage regulator DZ2 and optocoupler PC1B;

[0031] Among them, one end of the fuse F1 is connected to the live wire, and the other end of the fuse F1 is connected in parallel to one end of the varistor VDR1, one end of the capacitor CX1, one end of the resistor R1a, one end of the resistor R1c and the mutual inductance LF1 "1" terminal, one end of the resistor FR1 is connected in parallel to the neutral line, the other end of the varistor VDR1 and the second anode of the thyristor Q2, the other end of the resistor FR1 is connected in parallel to the other end of the capacitor CX1, the first anode of the thyristor Q2, the other end of the resistor R1b, the other end of the resistor R1d and the mutual inductance LF1 "2" terminal, the other end of the resistor R1a and the other end of the resistor R1c are connected in parallel to one end of the resistor R1b and one end of the resistor R1d, and the mutual inductance LF1 " The "3" terminal and the "4" terminal serve as the power output terminal of the AC power supply circuit 01; the "2" terminal of the bridge DB1 is connected to the "3" terminal of the mutual inductance LF1, the "3" terminal of the bridge DB1 is connected to the "4" terminal of the mutual inductance LF1, the "4" terminal of the bridge DB1 is grounded, the "1" terminal of the bridge DB1 is connected in parallel to one end of the capacitor C1a, one end of the capacitor C1b and the "1" terminal of the transformer TR1 of the RC filter circuit, and the other end of the capacitor C1a and the other end of the capacitor C1b are grounded; one end of the resistor R4a, one end of the resistor R4b, one end of the resistor R4c, one end of the resistor R4d and one end of the capacitor C1a are connected to the "1" terminal of the transformer TR1, The other end of resistor R4a, the other end of resistor R4b, the other end of resistor R4c, the other end of resistor R4d and the other end of capacitor C1a are connected to one end of resistor R5a, one end of resistor R5b and one end of resistor R5c, and the other end of resistor R5a, the other end of resistor R5b and the other end of resistor R5c are connected to the cathode of diode D1; the "2" terminal of transformer TR1 is connected to the anode of diode D1, the "3" terminal of transformer TR1 is connected to the anode of voltage regulator D6, the "4" terminal of transformer TR1 is grounded, the "5" terminal of transformer TR1 is connected to one end of inductor L1, and the "6" terminal of transformer TR1 is grounded; the anode of diode D6 is connected to resistor R19 One end of a, one end of resistor R19b and one end of resistor R19c are connected to terminal "3" of transformer TR1, the other end of resistor R19a, the other end of resistor R19b and the other end of resistor R19c are connected to one end of capacitor C9, the cathode of diode D6 and the other end of capacitor C9 are connected to one end of capacitor CD4, one end of capacitor CD5, one end of capacitor C11, the cathode of voltage regulator DZ3, one end of resistor R25 and one end of resistor R26, the other end of resistor R26 is connected to the anode of LED1, the other end of resistor R25, the other end of capacitor CD4, the other end of capacitor CD5, the other end of capacitor C11, the anode of voltage regulator DZ3 and the cathode of LED1 are grounded;One end of the resistor R20 is connected to the positive electrode of the DC power supply (+12V), the other end of the resistor R20 is connected in parallel to the positive electrode of the optocoupler PC1A and one end of the resistor R21, the negative electrode of the optocoupler PC1A and the other end of the resistor R21 are connected to one end of the capacitor C10 and the "2" terminal of the voltage regulator IC2, one end of the resistor R23 is connected to the output port, the other end of the resistor R23 is connected in parallel to one end of the resistor R22, the "1" terminal of the voltage regulator IC2, one end of the resistor R24a and one end of the resistor R24b, the other end of the resistor R22 is connected to the other end of the capacitor C10, the other end of the resistor R24a and the other end of the resistor R24b are connected to the voltage regulator IC2. The "3" terminal of C2 is grounded; the other end of the inductor L1 is connected to the positive electrode of the diode D2, the negative electrode of the diode D2 is connected in parallel to the positive electrode of the diode D3, one end of the capacitor CD2 and the other end of the resistor R14, the other end of the capacitor CD2 is grounded, the negative electrode of the diode D3 is connected in parallel to the series resistor R2a and one end of the resistor R2b, one end of the capacitor CD3 and the "5" terminal of the chip IC1, the other end of the series resistor R2a and the resistor R2b is connected to the other end of the resistor R1a, the other end of the capacitor CD3 is grounded, the "1" terminal of the chip IC1 is grounded, the "2" terminal of the chip IC1 is connected to one end of the inductor L2, the other end of the inductor L2 is grounded. The first terminal is connected in parallel to one end of capacitor C6, the "4" terminal of optocoupler PC1B and the negative electrode of voltage regulator DZ2, the "3" terminal of optocoupler PC1B is connected to one end of inductor L3, the positive electrode of voltage regulator DZ2, the other end of capacitor C6 and the other end of inductor L3 are grounded, the "4" terminal of chip IC1 is connected in parallel to one end of resistor R10a and one end of capacitor C3, the other end of resistor R10a is connected in parallel to one end of resistor R9a, one end of resistor R9b, one end of resistor R9c and one end of resistor R9d, the other end of capacitor C3, the other end of resistor R9a, the other end of resistor R9b, the other end of resistor R9c and the other end of resistor R9d One end is grounded, the chip IC1 "6" terminal is connected to one end of the resistor R6a, the other end of the resistor R6a is connected in parallel to one end of the resistor R6b and one end of the resistor R7, the other end of the resistor R7 is connected to the cathode of the diode D4, the other end of the resistor R6b is connected in parallel to one end of the capacitor C5, one end of the resistor R8, the anode of the diode D4 and the gate of the NMOS tube Q1, the other end of the capacitor C5 and the other end of the resistor R8 are grounded, the source of the NMOS tube Q1 is connected in parallel to one end of the capacitor C4b and the other end of the resistor R10a, and the other end of the capacitor C4b is connected in parallel to the drain of the NMOS tube Q1 and the "2" terminal of the transformer TR1. ;

[0032] Among them, capacitor CD2, capacitor CD3, capacitor CD4, and capacitor CD5 are all variable capacitors, chip IC1 is model OB2281AMP, and chip IC2 is model TL431.

[0033] The specific implementation method of the utility model is as follows: a fixed resistance resistor is used to replace the thermistor, and a bidirectional thyristor is connected in parallel to the resistor. When the switching power supply is turned on, the thyristor Q2 is cut off and does not conduct, and the current flows through the resistor FR1, which plays a role in suppressing the input surge current. When the switching power supply starts to work, a current will pass through the resistors R13 and R14 to give a trigger signal to the trigger pole of the thyristor Q2, so that the thyristor is turned on. After the thyristor is turned on, the input current will flow through the thyristor, and the current flowing through the resistor is extremely low, and the resistor is almost in a short-circuit state, which greatly reduces the power loss of the switching power supply.

[0034] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low power consumption surge current control circuit, characterized in that: The surge current protection control circuit comprises: an AC power supply circuit, a rectifier and filter circuit, a transformer circuit, a surge protection circuit, an output circuit and a pulse circuit, wherein the power input end of the AC power supply circuit is connected to an external AC power supply, the power output end of the AC power supply circuit is connected to the input end of the rectifier and filter circuit, the output end of the rectifier and filter circuit is connected to the input end of the transformer circuit, and the output end of the transformer circuit is respectively connected to the input end of the output circuit, the input end of the pulse circuit and the input end of the surge protection circuit; Among them, the surge protection circuit includes a thyristor Q2, a resistor R13 and a resistor R14, the AC power supply circuit includes a resistor FR1, the resistor FR1 is connected in series to the neutral line of the AC power supply, the thyristor Q2 is connected in parallel with the resistor FR1, and the first anode of the thyristor Q2 is connected to the power input end, the second anode of the thyristor Q2 is connected to the neutral line, the control electrode of the thyristor Q2 is connected to the power output end of the series resistor R13 and the resistor R14, and the power input end of the series resistor R13 and the resistor R14 is connected to the output end of the transformer circuit.

2. A low power consumption surge current protection control circuit according to claim 1, characterized in that: The AC power supply circuit also includes a fuse F1, a varistor VDR1, a capacitor CX1, a resistor R1a, a resistor R1c, a resistor R1b, a resistor R1d and a mutual inductance LF1. One end of the fuse F1 is connected to the live wire, and the other end of the fuse F1 is connected in parallel to one end of the varistor VDR1, one end of the capacitor CX1, one end of the resistor R1a, one end of the resistor R1c and a "1" terminal of the mutual inductance LF1. One end of the resistor FR1 is connected in parallel to the neutral line, the other end of the varistor VDR1 and the second anode of the thyristor Q2. The other end of the resistor FR1 is connected in parallel to the other end of the capacitor CX1, the first anode of the thyristor Q2, the other end of the resistor R1b, the other end of the resistor R1d and the "2" terminal of the mutual inductance LF1. The other ends of the resistor R1a and the other ends of the resistor R1c are connected to one end of the resistor R1b and one end of the resistor R1d. The "3" terminal and "4" terminal of the mutual inductance LF1 serve as the power output end of the AC power supply circuit.

3. A low power consumption surge current protection control circuit according to claim 1, characterized in that: The rectifier and filter circuit includes a bridge rectifier and filter circuit and an RC filter circuit. The input end of the bridge rectifier and filter circuit is connected to the power output end of the AC power supply circuit, the output end of the bridge rectifier and filter circuit is connected to the input end of the RC filter circuit, and the output end of the RC filter circuit is connected to the input end of the transformer circuit.

4. A low power consumption surge current protection control circuit according to claim 3, characterized in that: The bridge rectifier filter circuit includes a bridge DB1, a capacitor C1a and a capacitor C1b, the "2" terminal and the "3" terminal of the bridge DB1 are respectively connected to the power output end of the AC power supply circuit, the "4" terminal of the bridge DB1 is grounded, the "1" terminal of the bridge DB1 is connected in parallel to one end of the capacitor C1a, one end of the capacitor C1b and the input end of the RC filter circuit, and the other end of the capacitor C1a and the other end of the capacitor C1b are grounded.

5. A low power consumption surge current protection control circuit according to claim 3, characterized in that: The RC filter circuit includes a resistor R4a, a resistor R4b, a resistor R4c, a resistor R4d, a resistor R5a, a resistor R5b, a resistor R5c and a capacitor C1a. One end of the resistor R4a, one end of the resistor R4b, one end of the resistor R4c, one end of the resistor R4d and one end of the capacitor C1a are connected to the output end of the bridge rectifier filter circuit and the input end of the transformer circuit. The other ends of the resistor R4a, the other end of the resistor R4b, the other end of the resistor R4c, the other end of the resistor R4d and the other end of the capacitor C1a are connected to one end of the resistor R5a, one end of the resistor R5b and one end of the resistor R5c. The other ends of the resistor R5a, the other end of the resistor R5b and the other end of the resistor R5c are connected to the control end of the pulse circuit.

6. A low power consumption surge current protection control circuit according to claim 1, characterized in that: The transformer circuit includes a transformer TR1, wherein the "1" terminal and the "2" terminal of the transformer TR1 are respectively connected to the output end of the rectifier and filter circuit, the "3" terminal and the "4" terminal of the transformer TR1 are respectively connected to the input end of the output circuit, and the "5" terminal and the "6" terminal of the transformer TR1 are respectively connected to the input end of the pulse circuit.

7. A low power consumption surge current protection control circuit according to claim 1, characterized in that: The output circuit includes a DC output circuit and a voltage stabilizing circuit. The input end of the DC output circuit is connected to the output end of the voltage conversion circuit. The output end of the DC output circuit is connected in parallel to an output port and the input end of the voltage stabilizing circuit.

8. A low power consumption surge current protection control circuit according to claim 7, characterized in that: The DC output circuit includes a diode D6, a resistor R19a, a resistor R19b, a resistor R19c, a resistor R26, a resistor R25, a capacitor C9, a capacitor CD4, a capacitor CD5, a capacitor C11, a voltage regulator DZ3 and an LED1. The positive electrode of the diode D6 and one end of the resistor R19a, one end of the resistor R19b and one end of the resistor R19c are connected to the positive terminal of the output end of the transformer circuit. The other end of the resistor R19a, the other end of the resistor R19b and the other end of the resistor R19c are connected to the positive terminal of the output end of the transformer circuit. One end of the capacitor C9 is connected in common, the cathode of the diode D6 and the other end of the capacitor C9 are connected in common to one end of the capacitor CD4, one end of the capacitor CD5, one end of the capacitor C11, the cathode of the voltage regulator DZ3, one end of the resistor R25 and one end of the resistor R26, the other end of the resistor R26 is connected to the anode of LED1, and the cathode end of the output end of the transformer circuit is grounded together with the other end of the resistor R25, the other end of the capacitor CD4, the other end of the capacitor CD5, the other end of the capacitor C11, the anode of the voltage regulator DZ3 and the cathode of LED1.

9. The low power consumption surge current protection control circuit according to claim 7, characterized in that: The voltage stabilizing circuit includes a resistor R20, a resistor R21, a resistor R22, a resistor R23, a resistor R24a, a resistor R24b, an optocoupler PC1A, a voltage regulator IC2 and a capacitor C10, one end of the resistor R20 is connected to the positive electrode of the DC power supply, the other end of the resistor R20 is connected in parallel to the positive electrode of the optocoupler PC1A and one end of the resistor R21, the negative electrode of the optocoupler PC1A and the other end of the resistor R21 are commonly connected to one end of the capacitor C10 and the "2" terminal of the voltage regulator IC2, one end of the resistor R23 is connected to the output port, the other end of the resistor R23 is connected in parallel to one end of the resistor R22, the "1" terminal of the voltage regulator IC2, one end of the resistor R24a and one end of the resistor R24b, the other end of the resistor R22 is connected to the other end of the capacitor C10, the other end of the resistor R24a and the other end of the resistor R24b are commonly grounded with the "3" terminal of the voltage regulator IC2.

10. The low power consumption surge current protection control circuit according to claim 1, characterized in that: The pulse circuit includes a resistor R2a, a resistor R2b, a diode D2, a diode D3, an inductor L1, a capacitor CD2, a capacitor CD3, a resistor R7, a diode D4, an NMOS tube Q1, a capacitor C4b, a resistor R6a, a resistor R6b, a resistor R8, a capacitor C5, a resistor R10a, a resistor R9a, a resistor R9b, a resistor R9c, a resistor R9d, a capacitor C3, a capacitor CD3, a chip IC1, an inductor L2, a capacitor C6, an inductor L3, a voltage regulator tube DZ2 and an optical coupler PC1B. The positive terminal of the output end of the voltage transformer circuit is connected to one end of the inductor L1, and the other end of the inductor L1 is connected to The anode of the diode D2 is connected to the anode of the diode D3, one end of the capacitor CD2 and the input end of the surge protection circuit in parallel, the other end of the capacitor CD2 is grounded, the cathode of the diode D3 is connected in parallel to the series resistor R2a and one end of the resistor R2b, one end of the capacitor CD3 and the "5" terminal of the chip IC1, the other end of the series resistor R2a and the resistor R2b is connected to the AC power supply circuit, the other end of the capacitor CD3 is grounded, the "1" terminal of the chip IC1 is grounded, the "2" terminal of the chip IC1 is connected to one end of the inductor L2, the other end of the inductor L2 is connected in parallel to one end of the capacitor C6, the light The optical coupler PC1B "4" terminal is connected to the negative electrode of the voltage regulator tube DZ2, the optical coupler PC1B "3" terminal is connected to one end of the inductor L3, the positive electrode of the voltage regulator tube DZ2, the other end of the capacitor C6 and the other end of the inductor L3 are grounded, the chip IC1 "4" terminal is connected in parallel to one end of the resistor R10a and one end of the capacitor C3, the other end of the resistor R10a is connected in parallel to one end of the resistor R9a, one end of the resistor R9b, one end of the resistor R9c and one end of the resistor R9d, the other end of the capacitor C3, the other end of the resistor R9a, the other end of the resistor R9b, the other end of the resistor R9c and the other end of the resistor R9d are grounded, and the The "6" terminal of the chip IC1 is connected to one end of the resistor R6a, the other end of the resistor R6a is connected in parallel to one end of the resistor R6b and one end of the resistor R7, the other end of the resistor R7 is connected to the cathode of the diode D4, the other end of the resistor R6b is connected in parallel to one end of the capacitor C5, one end of the resistor R8, the anode of the diode D4 and the gate of the NMOS tube Q1, the other end of the capacitor C5 and the other end of the resistor R8 are grounded, the source of the NMOS tube Q1 is connected in parallel to one end of the capacitor C4b and the other end of the resistor R10a, and the other end of the capacitor C4b is connected in parallel to the drain of the NMOS tube Q1 and the input end of the voltage conversion circuit.

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