Miniaturized high-efficiency power supply module

Abstract

The utility model relates to the technical field of power supply circuits, in particular to a miniaturized high-efficiency power supply module, which is characterized in that the input end of an input filter circuit is connected with an external power supply, and the output end of the input filter circuit is connected with one end of the primary side of a first transformer; the input end of the on-off control circuit is connected with the other end of the primary side of the first transformer, and the output end of the on-off control circuit is grounded; the input end of the output filter circuit is connected with one end of the first secondary side of the first transformer, and the output end of the output filter circuit is the output end of the miniaturized high-efficiency power supply module; one end of the output synchronous rectification circuit is connected with the other end of the first secondary side of the first transformer, and the other end of the output synchronous rectification circuit is connected with the grounding end of the output filter circuit; according to the utility model, the output synchronous rectification circuit is arranged to replace the traditional diode rectification, so that the energy waste can be effectively reduced, and the output efficiency of the power supply module is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of power supply circuit, especially to a kind of miniaturization high efficiency power module. BACKGROUND

[0002] In new energy industry, as the core part of electronic system, how to reduce power output loss, guarantee the output efficiency of power supply, is the focus of the whole new energy line.

[0003] For example, in Chinese patent CN202320834518.X, a low-cost isolating switch power supply circuit is provided, which includes a waveform generation circuit, an open-loop flyback topology circuit and an output voltage stabilizing circuit. The 3-pin and 4-pin of the comparator U1 are connected by a resistor R3, and the capacitor C4 is connected between the 3-pin and 4-pin. The power supply VCC1 is connected to the 1-pin of the comparator U1 after being divided by resistors R5 and R7, and the resistor R8 is connected between the 1-pin and 4-pin of the comparator. The capacitor C5 is used as the power decoupling capacitor of the comparator U1, and is connected to the power pin 5-pin of the comparator U1. The open-loop flyback topology circuit includes a switching tube Q1, a coupling inductor T1, an RCD absorption circuit and an output load circuit. The 4-pin of the comparator U1 is connected to the gate of the switching tube Q1 through the resistor R6, the source of the switching tube Q1 is grounded, and the drain is connected to the positive electrode of the diode D1 and the 1-pin of the coupling inductor. The negative electrode of the diode D1 is connected to one end of the resistor R1 and the capacitor C1, and the other end of the resistor R1 and the capacitor C1 is connected to the 2-pin of the coupling inductor after being short-circuited. The 3-pin of the coupling inductor is connected to the positive electrode of the diode D2, and the resistor R2 is connected to the negative electrode of the diode D2 at one end and to the 4-pin of the coupling inductor at the other end.

[0004] However, in the above technical solution, the output rectifier circuit is composed of diode D2 and resistor R2, and the output voltage is rectified by diode to prevent the output voltage from being too high. If the output current is large, the loss of the diode itself is very large. For example, the output of the power supply is DC12V / 5A, and the voltage drop of the Schottky diode is about 0.7V. Therefore, the loss of the diode is at least 0.7V*5A=3.5W, which also causes energy waste and reduces the output efficiency of the power supply. UTILITY MODEL CONTENTS

[0005] In view of the above problems, the utility model provides a miniaturization high efficiency power module, which aims to reduce the energy waste in the power output process and improve the output efficiency of the power supply.

[0006] In order to achieve the above invention purpose, the utility model adopts the following technical solutions:

[0007] The application provides a miniaturized high-efficiency power module, comprising an input filter circuit, a first transformer, an output filter circuit, a on-off control circuit and an output synchronous rectification circuit; wherein the input end of the input filter circuit is connected with an external power supply, the output end of the input filter circuit is connected with one end of the primary side of the first transformer; the input end of the on-off control circuit is connected with the other end of the primary side of the first transformer, and the output end of the on-off control circuit is grounded; the input end of the output filter circuit is connected with one end of the first secondary side of the first transformer, and the output end of the output filter circuit is the output end of the miniaturized high-efficiency power module; one end of the output synchronous rectification circuit is connected with the other end of the first secondary side of the first transformer, and the other end of the output synchronous rectification circuit is connected with the grounding end of the output filter circuit.

[0008] Further, the input filter circuit comprises an inductor L1, one end of the inductor L1 is connected with the external power supply and a grounding capacitor C3 respectively, and the other end of the inductor L1 is connected with one end of the primary side of the first transformer, a grounding capacitor C4 and a grounding capacitor C5 respectively.

[0009] Further, the output filter circuit comprises an inductor L2, one end of the inductor L2 is connected with one end of the first secondary side of the first transformer and a grounding capacitor C6 respectively, and the other end of the inductor L2 is connected with a grounding capacitor C7 and serves as the output end of the miniaturized high-efficiency power module.

[0010] Further, the on-off control circuit comprises an N-type MOS tube Q2, the D pole of the N-type MOS tube Q2 is connected with the other end of the primary side of the first transformer, and the S pole of the N-type MOS tube Q2 is grounded; the G pole of the N-type MOS tube Q2 is connected with a grounding resistor R6 and serves as the control signal input end of the on-off control circuit.

[0011] Further, the output synchronous rectification circuit comprises an N-type MOS tube Q3 and a synchronous rectification chip U2; wherein the D pole of the N-type MOS tube Q3 is connected with the other end of the first secondary side of the first transformer, the S pole of the N-type MOS tube Q3 is connected with the grounding end of the output filter circuit; the VG pin of the synchronous rectification chip U2 is connected with one end of a resistor R11, the other end of the resistor R11 is connected with the G pole of the N-type MOS tube Q3 and one end of a resistor R9 respectively; the VCC pin of the synchronous rectification chip U2 is connected with the other end of the resistor R9 through a capacitor C11, the VCC pin of the synchronous rectification chip U2 is connected with the other end of the resistor R9 through the capacitor C11; the VD pin of the synchronous rectification chip U2 is connected with the D pole of the N-type MOS tube Q3 and is used for detecting voltage; the HVIN pin of the synchronous rectification chip U2 is connected with one end of a resistor R15 and a grounding capacitor C14 respectively, the other end of the resistor R15 is connected with the input end of the output filter circuit; the VSS pin of the synchronous rectification chip U2 is grounded, and the SET pin of the synchronous rectification chip U2 is connected with a grounding resistor R16.

[0012] Further, the power module further comprises: a current sampling circuit, an input end of the current sampling circuit being connected between the input filter circuit and the primary side of the first transformer; an active clamping circuit, one end of the active clamping circuit being connected between the primary side of the first transformer and the on-off control circuit, and the other end being grounded; a driving circuit, an input end of the driving circuit being connected to an output end of the current sampling circuit, and an output end of the driving circuit being connected to an input end of the on-off control circuit and an input end of the active clamping circuit; and an output feedback circuit, for collecting voltage data of the output filter circuit, converting the voltage data into a current signal, and sending the current signal to the driving circuit.

[0013] Further, the current sampling circuit comprises: a second transformer, a primary side of the second transformer being connected between the input filter circuit and the primary side of the first transformer; one end of a secondary side of the second transformer being connected to a positive electrode of a diode D3 and a grounding resistor R3 respectively, and the other end of the secondary side of the second transformer being grounded; and a negative electrode of the diode D3 being connected to a grounding resistor R5 and a grounding resistor R8 respectively, and serving as an output end of the current sampling circuit.

[0014] Further, the driving circuit comprises: a master chip U3, a driving chip U1 and a VCC power supply circuit; wherein a VIN pin of the master chip U3 is connected with an external power supply, a CS pin of the master chip U3 is respectively connected with a ground capacitor C19, one end of a resistor R25 and one end of a resistor R24; the other end of the resistor R25 is connected with an output end of a current sampling circuit; the other end of the resistor R24 is connected with one end of a resistor R20; the other end of the resistor R20 is connected with the external power supply; a COMP pin of the master chip U3 is respectively connected with an output end of an output feedback circuit and one end of a resistor R30, the other end of the resistor R30 is connected with a ground capacitor C20; a RT pin of the master chip U3 is connected with a ground resistor R23, a SS pin of the master chip U3 is connected with a ground capacitor C18; a GND pin and an EB pin of the master chip U3 are grounded; an OUT pin of the master chip U3 is respectively connected with one end of a resistor R7, a negative electrode of a diode D4, a positive electrode of a diode D5, one end of a resistor R13 and a ground resistor R14; a UV pin of the master chip U3 is respectively connected with a ground resistor R19, a ground capacitor C15 and one end of a resistor R18, the other end of the resistor R18 is connected with the external power supply through a resistor R17; a VCC pin of the master chip U3 is respectively connected with a ground capacitor C16 and an output end of the VCC power supply circuit; an INA pin of the driving chip U1 is respectively connected with the other end of the resistor R7, a positive electrode of the diode D4 and a ground capacitor C10; an INB pin of the driving chip U1 is respectively connected with the other end of the resistor R13, a negative electrode of the diode D5 and a ground capacitor C12; a GND pin of the driving chip U1 is grounded; an OUTA pin of the driving chip U1 is connected with one end of a resistor R10, the other end of the resistor R10 is connected with a control signal input end of a on-off control circuit; an OUTB pin of the driving chip U1 is connected with one end of a capacitor C13, the other end of the capacitor C13 is respectively connected with a control signal input end of an active clamping circuit and a positive electrode of a diode D6, a negative electrode of the diode D6 is grounded; a VDD pin of the driving chip U1 is connected with an output end of the VCC power supply circuit; wherein the VCC power supply circuit comprises: a diode D1, a positive electrode of the diode D1 is connected with one end of a second secondary side of a first transformer, a negative electrode of the diode D1 is connected with one end of a resistor R1, the other end of the resistor R1 is respectively connected with one end of a capacitor C1, one end of a resistor R2 and a C pole of an NPN type triode Q1; an E pole of the NPN type triode Q1 is connected with a ground capacitor C2 and serves as an output end of the VCC power supply circuit; a B pole of the NPN type triode Q1 is respectively connected with the other end of the resistor R2 and a negative electrode of a voltage stabilizing diode D2; the other end of the second secondary side of the first transformer is respectively connected with the other end of the capacitor C1, a positive electrode of the voltage stabilizing diode D2 and grounded.

[0015] Further, the output feedback circuit comprises: a voltage reference diode Q5, a positive electrode of the voltage reference diode Q5 is connected with one end of a resistor R27, a positive electrode of a diode D7 and ground respectively, a reference end of the voltage reference diode Q5 is connected with one end of a resistor R21, one end of a resistor R22, one end of a capacitor C17 and the other end of the resistor R27 respectively; the other end of the resistor R21 and the other end of the resistor R22 are used as an input end of the output feedback circuit and are connected with an output end of the output filter circuit; a negative electrode of the voltage reference diode Q5 is connected with a negative electrode of the diode D7, one end of a resistor R26 and a negative electrode of a light emitting source of a photo-coupler P1 respectively; the other end of the resistor R26 is connected with the other end of the capacitor C17; one end of a resistor R28 connected with a positive electrode of the light emitting source of the photo-coupler P1, the other end of the resistor R28 is used as another input end of the output feedback circuit and is connected with an input end of the output filter circuit; a positive electrode of a light receiver of the photo-coupler P1 is connected with a COMP pin of the main control chip U3, and a negative electrode of the light receiver is grounded.

[0016] Further, the active clamp circuit comprises: an N-type MOS tube Q4, a D pole of the N-type MOS tube Q4 is connected with one end of a capacitor C9, the other end of the capacitor C9 is connected between one end of a primary side of the first transformer and the on-off control circuit, a S pole of the N-type MOS tube Q4 is grounded, and a G pole of the N-type MOS tube Q4 is connected with a grounding resistor R12 and used as a control signal input end of the active clamp circuit.

[0017] The utility model discloses a beneficial effect is:

[0018] In the utility model, through setting up output synchronous rectification circuit to replace traditional diode rectification, can effectively reduce the waste of energy, promote the output efficiency of power module,

[0019] Still set up active clamp circuit to replace traditional RCD absorption circuit, can make the loss of peak voltage of power module reduce 0.3-0.5W, can reduce the loss of power module, further promote output efficiency. ACCURACY OF DRAWINGS

[0020] Figure 1 The whole circuit structure schematic diagram of power module provided in the embodiment of the application. DETAILED DESCRIPTION

[0021] In order to better understand the above technical scheme, the above technical scheme will be explained in detail in the following in conjunction with the drawings of the specification and specific implementation.

[0022] REFERENCE Figure 1As shown, the embodiment of the application discloses a miniaturized high-efficiency power module, comprising: an input filter circuit, a first transformer, an output filter circuit, an on-off control circuit and an output synchronous rectification circuit; wherein the input end of the input filter circuit is connected with an external power supply, and the output end of the input filter circuit is connected with one end of the primary side of the first transformer; the input end of the on-off control circuit is connected with the other end of the primary side of the first transformer, and the output end of the on-off control circuit is grounded; the input end of the output filter circuit is connected with one end of the first secondary side of the first transformer, and the output end of the output filter circuit is the output end of the miniaturized high-efficiency power module; one end of the output synchronous rectification circuit is connected with the other end of the first secondary side of the first transformer, and the other end of the output synchronous rectification circuit is connected with the grounding end of the output filter circuit.

[0023] In the embodiment, the input filter circuit comprises: an inductor L1, one end of the inductor L1 is connected with the external power supply and a grounding capacitor C3 respectively; the other end of the inductor L1 is connected with one end of the primary side of the first transformer, a grounding capacitor C4 and a grounding capacitor C5 respectively.

[0024] In addition, the output filter circuit comprises: an inductor L2, one end of the inductor L2 is connected with one end of the first secondary side of the first transformer and a grounding capacitor C6 respectively; the other end of the inductor L2 is connected with a grounding capacitor C7 and serves as the output end of the miniaturized high-efficiency power module.

[0025] It is worth mentioning that, in the utility model, the input filter circuit and the output filter circuit are both π type filter circuits, and by arranging the input filter circuit and the output filter circuit, the unwanted harmonics in the current can be removed, the high-frequency noise and interference can be reduced, and the output efficiency of the whole power module can be ensured.

[0026] Specifically, the on-off control circuit comprises: an N-type MOS tube Q2, the D pole of the N-type MOS tube Q2 is connected with the other end of the primary side of the first transformer, and the S pole of the N-type MOS tube Q2 is grounded; the G pole of the N-type MOS tube Q2 is connected with a grounding resistor R6 and serves as the control signal input end of the on-off control circuit; in specific use, by transmitting the control signal to the G pole of the N-type MOS tube Q2, the on-off of the whole power module can be controlled, the response speed can be improved, and the output efficiency of the power module can be ensured.

[0027] Specifically, the output synchronous rectification circuit comprises an N-type MOS tube Q3 and a synchronous rectification chip U2; wherein one end of the D pole of the N-type MOS tube Q3 is connected to the other end of the first secondary side of the first transformer, and the S pole of the N-type MOS tube Q3 is connected to the ground end of the output filter circuit; one end of the VG pin of the synchronous rectification chip U2 is connected to one end of the resistor R11, and the other end of the resistor R11 is connected to the G pole of the N-type MOS tube Q3 and one end of the resistor R9 respectively; the VCC pin of the synchronous rectification chip U2 is connected to the other end of the resistor R9 through the capacitor C11, and the VCC pin of the synchronous rectification chip U2 is connected to the other end of the resistor R9 through the capacitor C11; the VD pin of the synchronous rectification chip U2 is connected to the D pole of the N-type MOS tube Q3 and used for detecting voltage; the HVIN pin of the synchronous rectification chip U2 is connected to one end of the resistor R15 and the ground capacitor C14 respectively, and the other end of the resistor R15 is connected to the input end of the output filter circuit; the VSS pin of the synchronous rectification chip U2 is grounded, and the SET pin of the synchronous rectification chip U2 is connected with the ground resistor R16.

[0028] With the output of the power module being DC 12V / 5A and the N-type MOS tube Q3 with an internal resistance of 10mΩ as an example, the loss is 5A*5A*10mΩ=0.25W; in the utility model, the N-type MOS tube Q3 is arranged in the output synchronous rectification circuit, the traditional diode rectification is replaced by the N-type MOS tube Q3, the waste of energy can be effectively reduced, and the output efficiency of the power module is improved.

[0029] It can be understood that the synchronous rectification chip U2 is a self-driven chip, by arranging the synchronous rectification chip U2, the D pole voltage of the N-type MOS tube Q3 and the output voltage of the output filter circuit can also be detected, a driving voltage is generated to open the N-type MOS tube Q3 and realize synchronous rectification.

[0030] Specifically, the power module further comprises: a current sampling circuit, an input end of the current sampling circuit being connected between the input filter circuit and the primary side of the first transformer; an active clamping circuit, one end of the active clamping circuit being connected between the primary side of the first transformer and the on-off control circuit, and the other end being grounded; a driving circuit, an input end of the driving circuit being connected to an output end of the current sampling circuit, and an output end of the driving circuit being connected to an input end of the on-off control circuit and an input end of the active clamping circuit; and an output feedback circuit, used for collecting voltage data of the output filter circuit and converting the voltage data into a current signal, and sending the current signal to the driving circuit.

[0031] Specifically, the current sampling circuit comprises: a second transformer, a primary side of the second transformer being connected between the input filter circuit and the primary side of the first transformer; one end of a secondary side of the second transformer being connected to the positive pole of the diode D3 and the ground resistor R3 respectively, and the other end of the secondary side of the second transformer being grounded; and the negative pole of the diode D3 being connected to the ground resistor R5 and the ground resistor R8 respectively and serving as an output end of the current sampling circuit.

[0032] In the embodiment, the current real-time change of the input filter circuit output is obtained by the second transformer and converted into a current signal input into the driving circuit.

[0033] Specifically, the driving circuit comprises a master control chip U3, a driving chip U1 and a VCC power supply circuit; wherein the VIN pin of the master control chip U3 is connected with an external power supply, the CS pin of the master control chip U3 is respectively connected with one end of a grounding capacitor C19, one end of a resistor R25 and one end of a resistor R24; the other end of the resistor R25 is connected with an output end of a current sampling circuit; the other end of the resistor R24 is connected with one end of a resistor R20; the other end of the resistor R20 is connected with an external power supply; the COMP pin of the master control chip U3 is respectively connected with an output end of an output feedback circuit and one end of a resistor R30, the other end of the resistor R30 is connected with a grounding capacitor C20; the RT pin of the master control chip U3 is connected with a grounding resistor R23, the SS pin of the master control chip U3 is connected with a grounding capacitor C18; the GND pin and the EB pin of the master control chip U3 are grounded; the OUT pin of the master control chip U3 is respectively connected with one end of a resistor R7, a negative electrode of a diode D4, a positive electrode of a diode D5, one end of a resistor R13 and a grounding resistor R14; the UV pin of the master control chip U3 is respectively connected with a grounding resistor R19, a grounding capacitor C15 and one end of a resistor R18, the other end of the resistor R18 is connected with an external power supply through a resistor R17; the VCC pin of the master control chip U3 is respectively connected with a grounding capacitor C16 and an output end of the VCC power supply circuit.

[0034] Specifically, the INA pin of the driving chip U1 is respectively connected with the other end of the resistor R7, a positive electrode of the diode D4 and a grounding capacitor C10; the INB pin of the driving chip U1 is respectively connected with the other end of the resistor R13, a negative electrode of the diode D5 and a grounding capacitor C12; the GND pin of the driving chip U1 is grounded; the OUTA pin of the driving chip U1 is connected with one end of a resistor R10, the other end of the resistor R10 is connected with a control signal input end of a on-off control circuit; the OUTB pin of the driving chip U1 is connected with one end of a capacitor C13, the other end of the capacitor C13 is respectively connected with a control signal input end of an active clamping circuit and a positive electrode of a diode D6, a negative electrode of the diode D6 is grounded; the VDD pin of the driving chip U1 is connected with an output end of the VCC power supply circuit.

[0035] The VCC power supply circuit comprises a diode D1, one end of a second secondary side of a first transformer is connected to the anode of the diode D1, one end of a resistor R1 is connected to the cathode of the diode D1, the other end of the resistor R1 is connected to one end of a capacitor C1, one end of a resistor R2 and the C terminal of an NPN triode Q1 respectively; the E terminal of the NPN triode Q1 is connected to a grounding capacitor C2 and serves as an output terminal of the VCC power supply circuit; the B terminal of the NPN triode Q1 is connected to the other end of the resistor R2 and the cathode of a voltage stabilizing diode D2 respectively; the other end of the second secondary side of the first transformer is connected to the other end of the capacitor C1, the anode of the voltage stabilizing diode D2 and the ground.

[0036] In the embodiment, the VCC power supply circuit is arranged to provide stable current for the started master control chip U3 and the driving chip U1, thereby ensuring the stable operation of the master control chip U3 and the driving chip U1.

[0037] Specifically, the output feedback circuit comprises a voltage reference diode Q5, the anode of the voltage reference diode Q5 is connected to one end of a resistor R27, the anode of a diode D7 and the ground respectively, the reference terminal of the voltage reference diode Q5 is connected to one end of a resistor R21, one end of a resistor R22, one end of a capacitor C17 and the other end of the resistor R27 respectively; the other end of the resistor R21 and the other end of the resistor R22 serve as one input terminal of the output feedback circuit and are connected to the output terminal of the output filter circuit; the cathode of the voltage reference diode Q5 is connected to the cathode of the diode D7, one end of a resistor R26 and the negative electrode of the light emitting source of a photo-coupler P1 respectively; the other end of the resistor R26 is connected to the other end of the capacitor C17; one end of a resistor R28 is connected to the positive electrode of the light emitting source of the photo-coupler P1, the other end of the resistor R28 serves as the other input terminal of the output feedback circuit and is connected to the input terminal of the output filter circuit; the positive electrode of the light receiver of the photo-coupler P1 is connected to the COMP pin of the master control chip U3, and the negative electrode of the light receiver of the photo-coupler P1 is grounded.

[0038] In the embodiment, the positive electrode and the negative electrode of the light emitting source of the photo-coupler P1 are connected to the input terminal and the output terminal of the output filter circuit, the voltage between the two terminals of the output filter circuit is converted into a current signal by the light receiver of the photo-coupler P1 and is transmitted to the master control chip U3; the master control chip U3 is a PWM chip, the master control chip U3 transmits a start-stop signal to the driving chip U1, the driving force of the master control chip U3 is improved by the driving chip U1, and the on-off control of the on-off control circuit and the active clamp circuit is realized.

[0039] It is worth mentioning that the duty cycle of the master control chip U3 can be controlled by the voltage reference diode Q5 and the photo-coupler P1 to realize the stability of the output of the power supply module.

[0040] Preferably, the RT pin of the master chip U3 is connected with a grounding resistor R23, and by setting the grounding resistor R23, a higher frequency can be obtained, and the overall efficiency of the power module is improved.

[0041] Specifically, the active clamp circuit comprises an N-type MOS tube Q4, one end of the D pole of the N-type MOS tube Q4 is connected with one end of the capacitor C9, the other end of the capacitor C9 is connected between one end of the primary side of the first transformer and the on-off control circuit, the S pole of the N-type MOS tube Q4 is grounded, and the G pole of the N-type MOS tube Q4 is connected with the grounding resistor R12 and serves as a control signal input end of the active clamp circuit.

[0042] In the embodiment, the active clamp circuit is arranged to replace the traditional RCD absorption circuit, the N-type MOS tube Q4 is arranged to reduce the peak voltage of the power device (the peak voltage is reduced by 30-50%), the loss of the peak voltage is reduced by 0.3-0.5 W, the loss of the power module can be reduced, and the output efficiency is further improved.

[0043] It is worth mentioning that the various circuit devices of the power module can adopt the SMD device, the integration degree is high, the product miniaturization can be realized, the overall volume of the power module is reduced under the premise of ensuring the quality.

[0044] Those skilled in the art will understand that, although the preferred embodiments of the present application have been described, those skilled in the art can make further changes and modifications to the embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application. Obviously, those skilled in the art can make various modifications and changes to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and changes of the present application fall within the scope of the claims of the present application, the present application also intends to include these modifications and changes.

Claims

1. A miniaturized high efficiency power module characterized by, The application relates to a small-sized high-efficiency power supply module. The small-sized high-efficiency power supply module comprises an input filter circuit, a first transformer, an output filter circuit, an on-off control circuit and an output synchronous rectification circuit. The input end of the input filter circuit is connected with an external power supply, and the output end of the input filter circuit is connected with one end of the primary side of the first transformer. The input end of the output filter circuit is connected with one end of the first secondary side of the first transformer, and the output end of the output filter circuit is the output end of the small-sized high-efficiency power supply module. One end of the output synchronous rectification circuit is connected with the other end of the first secondary side of the first transformer, and the other end of the output synchronous rectification circuit is connected with the grounding end of the output filter circuit. The input filter circuit comprises an inductor L1, one end of the inductor L1 is connected with the external power supply and a grounding capacitor C3 respectively, and the other end of the inductor L1 is connected with one end of the primary side of the first transformer, a grounding capacitor C4 and a grounding capacitor C5 respectively.

2. The miniaturized high efficiency power module of claim 1, wherein, The output filter circuit comprises an inductor L2, one end of the inductor L2 is connected with one end of the first secondary side of the first transformer and a grounding capacitor C6 respectively, and the other end of the inductor L2 is connected with a grounding capacitor C7 and serves as the output end of the small-sized high-efficiency power supply module.

3. The miniaturized high efficiency power module of claim 1, wherein, The on-off control circuit comprises an N-type MOS tube Q2, the D pole of the N-type MOS tube Q2 is connected with the other end of the primary side of the first transformer, the S pole of the N-type MOS tube Q2 is grounded, and the G pole of the N-type MOS tube Q2 is connected with a grounding resistor R6 and serves as the control signal input end of the on-off control circuit. The output synchronous rectification circuit comprises an N-type MOS tube Q3 and a synchronous rectification chip U2.

4. The miniaturized high efficiency power module of claim 1, wherein, The D pole of the N-type MOS tube Q3 is connected with the other end of the first secondary side of the first transformer, and the S pole of the N-type MOS tube Q3 is connected with the grounding end of the output filter circuit.

5. The miniaturized high efficiency power module of claim 1, wherein, The VG pin of the synchronous rectification chip U2 is connected with one end of a resistor R11, the other end of the resistor R11 is connected with the G pole of the N-type MOS tube Q3 and one end of a resistor R9 respectively, the VCC pin of the synchronous rectification chip U2 is connected with the other end of the resistor R9 through a capacitor C11, and the VD pin of the synchronous rectification chip U2 is connected with the D pole of the N-type MOS tube Q3 and used for detecting voltage. The HVIN pin of the synchronous rectification chip U2 is connected with one end of a resistor R15 and a grounding capacitor C14 respectively, and the other end of the resistor R15 is connected with the input end of the output filter circuit. The VSS pin of the synchronous rectification chip U2 is grounded, and the SET pin of the synchronous rectification chip U2 is connected with a grounding resistor R16. The small-sized high-efficiency power supply module further comprises a current sampling circuit, an active clamp circuit and a driving circuit. The input end of the current sampling circuit is connected between the input filter circuit and the primary side of the first transformer. One end of the active clamp circuit is connected between the on-off control circuit and the primary side of the first transformer, and the other end of the active clamp circuit is grounded.

6. The miniaturized high efficiency power module of claim 1, wherein, The input end of the driving circuit is connected with the output end of the current sampling circuit, the output end of the driving circuit is connected with the input end of the on-off control circuit and the input end of the active clamp circuit. ​ ​ ​ An output feedback circuit is configured to collect voltage data of the output filter circuit and convert the voltage data into a current signal, and send the current signal to the driving circuit.

7. The miniaturized high efficiency power module of claim 6, wherein, The current sampling circuit comprises: The second transformer has a primary winding connected between the input filter circuit and the primary winding of the first transformer; One end of the secondary winding of the second transformer is connected to the anode of diode D3 and a grounding resistor R3, and the other end of the secondary winding of the second transformer is grounded; the cathode of diode D3 is connected to a grounding resistor R5 and a grounding resistor R8, and serves as an output terminal of the current sampling circuit.

8. The miniaturized high efficiency power module of claim 6, wherein, The driving circuit comprises a main control chip U3, a driving chip U1 and a VCC power supply circuit; The VIN pin of the main control chip U3 is connected to an external power supply, the CS pin of the main control chip U3 is connected to a grounding capacitor C19, one end of a resistor R25 and one end of a resistor R24; the other end of the resistor R25 is connected to the output terminal of the current sampling circuit; the other end of the resistor R24 is connected to one end of a resistor R20; the other end of the resistor R20 is connected to the external power supply; The COMP pin of the main control chip U3 is connected to the output terminal of the output feedback circuit and one end of a resistor R30, and the other end of the resistor R30 is connected to a grounding capacitor C20; The RT pin of the main control chip U3 is connected to a grounding resistor R23, and the SS pin of the main control chip U3 is connected to a grounding capacitor C18; the GND pin and the EB pin of the main control chip U3 are grounded; the OUT pin of the main control chip U3 is connected to one end of a resistor R7, the cathode of a diode D4, the anode of a diode D5, one end of a resistor R13 and a grounding resistor R14; The UV pin of the main control chip U3 is connected to a grounding resistor R19, a grounding capacitor C15 and one end of a resistor R18, and the other end of the resistor R18 is connected to an external power supply through a resistor R17; The VCC pin of the main control chip U3 is connected to a grounding capacitor C16 and the output terminal of the VCC power supply circuit; The INA pin of the driving chip U1 is connected to the other end of the resistor R7, the anode of the diode D4 and a grounding capacitor C10; The INB pin of the driving chip U1 is connected to the other end of the resistor R13, the cathode of the diode D5 and a grounding capacitor C12; The GND pin of the driving chip U1 is grounded; The OUTA pin of the driving chip U1 is connected to one end of a resistor R10, and the other end of the resistor R10 is connected to a control signal input terminal of the on-off control circuit; The OUTB pin of the driving chip U1 is connected to one end of a capacitor C13, and the other end of the capacitor C13 is connected to a control signal input terminal of the active clamping circuit and the anode of a diode D6, and the cathode of the diode D6 is grounded; The VDD pin of the driving chip U1 is connected to the output terminal of the VCC power supply circuit; The VCC power supply circuit comprises: The anode of a diode D1 is connected to one end of the second secondary winding of the first transformer, the cathode of the diode D1 is connected to one end of a resistor R1, and the other end of the resistor R1 is connected to one end of a capacitor C1, one end of a resistor R2 and the C terminal of an NPN triode Q1; The E terminal of the NPN triode Q1 is connected to a grounding capacitor C2 and serves as an output terminal of the VCC power supply circuit. The B pole of the NPN type triode Q1 is connected with the other end of the resistance R2 and the negative pole of the voltage stabilizing diode D2 respectively; The other end of the second secondary side of the first transformer is connected with the other end of the capacitor C1, the positive pole of the voltage stabilizing diode D2 and the ground respectively.

9. The miniaturized high efficiency power module of claim 8, wherein, The output feedback circuit comprises: The positive pole of the voltage reference diode Q5 is connected with the one end of the resistance R27, the positive pole of the diode D7 and the ground respectively, and the reference end of the voltage reference diode Q5 is connected with the one end of the resistance R21, the one end of the resistance R22, the one end of the capacitor C17 and the other end of the resistance R27 respectively; the other end of the resistance R21 and the other end of the resistance R22 are taken as one input end of the output feedback circuit and are connected with the output end of the output filter circuit; The negative pole of the voltage reference diode Q5 is connected with the negative pole of the diode D7, the one end of the resistance R26 and the negative pole of the light emitting source of the photo-coupler P1 respectively; the other end of the resistance R26 is connected with the other end of the capacitor C17; The positive pole of the light emitting source of the photo-coupler P1 is connected with the one end of the resistance R28, and the other end of the resistance R28 is taken as the other input end of the output feedback circuit and is connected with the input end of the output filter circuit; The positive pole of the light receiver of the photo-coupler P1 is connected with the COMP pin of the main control chip U3, and the negative pole of the light receiver of the photo-coupler P1 is grounded.

10. The miniaturized high efficiency power module of claim 6, wherein, The active clamp circuit comprises: the N type MOS tube Q4, the D pole of the N type MOS tube Q4 is connected with the one end of the capacitor C9, the other end of the capacitor C9 is connected between the one end of the primary side of the first transformer and the on-off control circuit, the S pole of the N type MOS tube Q4 is grounded, and the G pole of the N type MOS tube Q4 is connected with the grounding resistance R12 and taken as the control signal input end of the active clamp circuit respectively.

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