CN115765453B

CN115765453B - Control circuit of zero-current switch resonance DC/DC power supply

Info

Publication number: CN115765453B
Application number: CN202310030132.8A
Authority: CN
Inventors: 边万平
Original assignee: Shaanxi Zhongke Tiandi Aviation Module Co ltd
Current assignee: Shaanxi Zhongke Tiandi Aviation Module Co ltd
Priority date: 2023-01-10
Filing date: 2023-01-10
Publication date: 2023-04-21
Anticipated expiration: 2043-01-10
Also published as: CN115765453A

Abstract

The invention discloses a control circuit of a zero-current switching resonance DC/DC power supply, which comprises a multifunctional controllable power supply circuit, a current mirror circuit, a large dynamic current adjusting circuit, a soft start circuit, a multivibrator circuit, a pulse frequency synchronization and prohibition circuit, an output pulse width adjusting circuit, a current mirror output voltage amplitude control circuit and an output current driving and dead time control circuit, wherein the current mirror circuit is connected with the control circuit; the multifunctional controllable power supply circuit is a power supply; the current mirror circuit and the large dynamic current adjusting circuit are connected with the soft start circuit, the multivibrator circuit, the pulse frequency synchronization and prohibition circuit and the current mirror output voltage amplitude control circuit; the multivibrator circuit and the pulse frequency synchronization and prohibition circuit are respectively connected with the output pulse width adjusting circuit, the current mirror output voltage amplitude control circuit, the output current driving and dead time control circuit. The invention can realize the adjustment of the switching frequency by the external feedback signal in a wider range, and has complete functions and low cost.

Description

Control circuit of zero-current switch resonance DC/DC power supply

Technical Field

The invention relates to the technical field of electronics, in particular to a control circuit of a zero-current switch resonance DC/DC power supply.

Background

With the continuous development of power electronics technology, the performance requirements on power technology are higher and higher, and the switch power supply is also developed towards miniaturization, high switching frequency, low switching loss, high efficiency, good EMI characteristics, fast dynamic response and the like. One major approach to achieving these performance improvements is to employ soft-switching resonance techniques and to increase the switching frequency of the switching power supply.

At present, the overseas zero-current switch resonance technology is adopted to realize the industrialization of the module power supply, mainly in the U.S. of VICOR company, and the VICOR company develops a self-used special control integrated circuit to carry out technology and patent protection, and because the control integrated circuit of the special zero-current switch technology is limited by technical patents, the technical difficulty of developing the power module of the zero-current switch type by other companies is great, and the following points are mainly found in the application:

firstly, the special voltage control oscillator integrated circuit which can realize the continuous adjustability of the frequency in a large dynamic range (0.05 kHz-1.2 MHz) and can be controlled synchronously externally is not capable of realizing the commercialized application of the power module of the zero-current switch resonance technology. The existing voltage frequency conversion control circuit has the problems that an input control signal is not suitable, the output dynamic range is insufficient, or external synchronous control and prohibition are not available, and the existing voltage frequency conversion control circuit cannot be applied to commercialization of a power module adopting a zero-current switch resonance technology and can only be used for function verification of partial functions.

The special control integrated circuit for realizing zero current detection and turning off the main power MOSFEET switching device in real time does not exist, because the zero current turning-off function is required to be realized in the full input voltage range, the switching-on pulse time is required to adapt to the specific current resonance time and is not a fixed value, the zero current detection and the real-time turning-off function cannot be realized, the zero current turning-off function in the full range cannot be realized, the product performance is reduced, and the advantages of the zero current switching resonance technology cannot be reflected.

The combined control circuit of a plurality of functional circuits capable of realizing the zero-current switching resonance technology does not comprise a power supply circuit capable of detecting input voltage and control signals, a circuit capable of realizing external synchronization and prohibition functions, an oscillating circuit capable of adjusting switching frequency through a feedback signal, a circuit capable of realizing zero-current detection and switching off a main power device in real time, and a circuit capable of realizing soft start of a power supply and dead time control of switching. And the control circuit is designed and developed according to the technical requirement of the zero-current switch resonance circuit, so that the technical requirement of zero-current switch resonance is realized, the input voltage range required by commercialization of the power module is wide, the external synchronization, the external prohibition, the external parallel application and the external output voltage adjustment are realized, and the control circuit has the functions of input under-voltage, output over-voltage, over-temperature protection and the like.

Disclosure of Invention

The invention aims to provide a control circuit of a zero-current switching resonance DC/DC power supply, which solves the problem that no special control integrated circuit for the zero-current switching resonance technology exists at present.

In order to achieve the above purpose, the present invention provides the following technical solutions:

the control circuit of the zero-current switching resonance DC/DC power supply is characterized by comprising the following seven sub-circuits: the multi-functional controllable power supply circuit, the current mirror circuit and the large dynamic current adjusting circuit, the soft start circuit, the multivibrator circuit, the pulse frequency synchronizing and prohibiting circuit, the output pulse width adjusting circuit, the current mirror output voltage amplitude control circuit and the output current driving and dead time control circuit; the multifunctional controllable power supply circuit is used as a power supply and connected with other sub-circuits; the current mirror circuit and the large dynamic current adjusting circuit are connected with the soft start circuit, the multivibrator circuit, the pulse frequency synchronization and prohibition circuit and the current mirror output voltage amplitude control circuit; the multivibrator circuit and the pulse frequency synchronization and prohibition circuit are respectively connected with the output pulse width adjusting circuit, the current mirror output voltage amplitude control circuit, the output current driving and dead time control circuit.

Further, the multifunctional controllable power supply circuit comprises a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a controllable silicon device IC1, a reference source integrated circuit IC2, a reference source integrated circuit IC3, a reference source integrated circuit IC4, a diode D1, a diode D2, a triode Q1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5 and a capacitor C6; the emitter of the triode Q1 is simultaneously connected with one end of a resistor R8 and the anode of a diode D1, and the connected common end is used as a power input end Vic of a multifunctional controllable power supply circuit and is connected with the power input end of a control circuit of the zero-current switch resonance DC/DC power supply; the collector of the triode Q1 is simultaneously connected with the anode of the capacitor C4, one end of the resistor R11, the anode of the diode D2 and the input end of the reference source integrated circuit IC4, and the connected common end VDD is used as a node of the power supply output of the multifunctional controllable power supply circuit; the base electrode of the triode Q1 is simultaneously connected with the other end of the resistor R8 and one end of the resistor R9; the output end of the reference source integrated circuit IC4 is connected with one end of a capacitor C6, and the connected common end is used as a 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the resistor R11 is connected with one end of the capacitor C5, the 1 st pin and the 2 nd pin of the reference source integrated circuit IC3, and the connected common end is used as an electrical network port Vref1 of the multifunctional controllable power supply circuit to be provided for the current mirror output voltage amplitude control circuit; the 2 nd pin of the reference source integrated circuit IC2 is simultaneously connected with the other end of the resistor R9 and one end of the capacitor C3; the 1 st pin of the reference source integrated circuit IC2 is simultaneously connected with one end of a resistor R5, one end of a resistor R6, one end of a resistor R10 and the other end of a capacitor C3; the other end of the resistor R10 is connected with the cathode of the diode D2; the 3 rd pin of the reference source integrated circuit IC2 is connected with the other end of the resistor R6, one end of the resistor R3, one end of the resistor R1, one end of the capacitor C2, the other end of the capacitor C6, the other end of the capacitor C5, the negative electrode of the capacitor C4, the 2 nd pin of the silicon controlled device IC1, the 3 rd pin of the reference source integrated circuit IC3 and the grounding end of the reference source integrated circuit IC4, and the connected common end is used as a grounding common end of a multifunctional controllable power supply circuit and a control circuit of the zero-current switching resonance DC/DC power supply; the other end of the resistor R5 is connected with one end of the resistor R4; the cathode of the diode D1 is connected with one end of a resistor R7; the 1 st pin of the silicon controlled device IC1 is simultaneously connected with the other end of the resistor R4 and the other end of the resistor R7, and the connected common end is used as a voltage input Vi port of the multifunctional controllable power supply circuit; the 3 rd pin of the silicon controlled device IC1 is simultaneously connected with the other end of the capacitor C2, the other end of the resistor R3 and one end of the resistor R2; the other end of the resistor R2 is connected with the other end of the resistor R1 and the other end of the capacitor C1, and the connected common end is used as an input RT/OV port of the multifunctional controllable power supply circuit.

Further, the current mirror circuit and the large dynamic current adjusting circuit comprise a resistor R12, a resistor R13, a resistor R14, a resistor R15, a resistor R16, a triode Q2, a triode Q3, a triode Q4, a junction field effect transistor Q5, a capacitor C7, a capacitor C8 and a capacitor C9; the emitter of the triode Q2 is connected with the emitter of the triode Q3, and the public end of the connection is connected with an output node VDD of the multifunctional controllable power supply circuit; the base electrode of the triode Q2 is connected with the base electrode of the triode Q3, the collector electrode of the triode Q3 and the emitter electrode of the triode Q4; the collector of the triode Q2 is simultaneously connected with the base of the triode Q4, one end of a resistor R12, one end of a resistor R13 and one end of a capacitor C8; the other end of the resistor R12 is connected with one end of the resistor R14, one end of the capacitor C7, one end of the capacitor C9 and the 3 rd pin of the junction field effect transistor Q5, and the connected common end is used as an input port FB of the current mirror circuit and the large dynamic current regulating circuit and is used as a feedback signal input end of the control circuit of the zero current switching resonance DC/DC power supply; the 1 st pin of the junction field effect transistor Q5 is connected with the other end of the resistor R13; the 2 nd pin of the junction field effect transistor Q5 is connected with one end of a resistor R15, one end of a resistor R16 and the other end of a capacitor C9; the other end of the resistor R15 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the collector of the triode Q4 is connected with the other end of the capacitor C8, and the connected common end is used as a current output end Iin of the current mirror circuit and the large dynamic current regulating circuit; the other end of the capacitor C7 is connected with the other end of the resistor R14 and the other end of the resistor R16, and the common end of the connection is connected with the common ground end of the control circuit of the zero-current switching resonance DC/DC power supply.

Further, the soft start circuit comprises a resistor R17, a resistor R18, a triode Q6, a capacitor C10, a capacitor C11 and a capacitor C12; one end of the capacitor C10 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the capacitor C10 is connected with one end of the resistor R17 and one end of the resistor R18; the other end of the resistor R18 is connected with one end of the capacitor C11 and the base electrode of the triode Q6; the collector of the triode Q6 is connected with one end of a capacitor C12, and the public end of the connection is connected with a current mirror circuit and a current output end Iin of the large dynamic current regulating circuit; the other end of the resistor R17 is simultaneously connected with the other end of the capacitor C11, the emitter of the triode Q6 and the other end of the capacitor C12, and the common end of the connection is connected with the common ground end of the control circuit of the zero-current switching resonance DC/DC power supply.

Further, the multivibrator circuit and the pulse frequency synchronization and prohibition circuit comprise a resistor R19, a resistor R20, a resistor R21, a diode D3, a diode D4, a capacitor C13, a capacitor C14, a capacitor C15 and an integrated circuit IC5; one end of the resistor R19 is connected with the current mirror circuit and the current output end Iin of the large dynamic current adjusting circuit; the other end of the resistor R19 is connected with one end of the resistor R20 and the anode of the diode D3; the cathode of the diode D3 is connected with a synchronous port SYNC of a control circuit of the zero-current switching resonance DC/DC power supply; the other end of the resistor R20 is connected with the anode of the diode D4, one end of the capacitor C14 and the 2 nd pin of the integrated circuit IC5; the cathode of the diode D4 is connected with an output port Bout of a control circuit of the zero-current switching resonance DC/DC power supply; one end of the capacitor C13 is simultaneously connected with one end of the resistor R21, the 3 rd pin of the integrated circuit IC5 and the 16 th pin of the integrated circuit IC5, and the public end of the connection is connected with the 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the resistor R21 is connected with one end of the capacitor C15 and the 15 th pin of the integrated circuit IC5, and the connected common end is used as an RC network end to be connected with an output pulse width adjusting circuit; the other end of the capacitor C15 is connected with the other end of the capacitor C14, the other end of the capacitor C13, the 1 st pin of the integrated circuit IC5, the 8 th pin of the integrated circuit IC5 and the 14 th pin of the integrated circuit IC5, and the public end of the connection is connected with the public grounding end of the control circuit of the zero-current switch resonance DC/DC power supply; the 13 th pin of the integrated circuit IC5 is used as an output port Ao of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; the 4 th pin of the integrated circuit IC5 serves as the output port Bo of the multivibrator circuit and the pulse frequency synchronization and disable circuit.

Further, the output pulse width adjusting circuit comprises a resistor R22, a resistor R23, a diode D5, a diode D6, a diode D7, a diode D8, a capacitor C16 and a capacitor C17; one end of the resistor R23 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the resistor R23 is connected with one end of the resistor R22, one end of the capacitor C16 and the cathode of the diode D6; the anode of the diode D6 is connected with the other end of the resistor R22, the anode of the diode D5, the anode of the diode D7, the cathode of the diode D8 and one end of the capacitor C17; the cathode of the diode D5 is connected with the RC network end of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; the cathode of the diode D7 is connected with an output port Aout of the dead time control circuit; the other end of the capacitor C17 is connected with an input port GD of a control circuit of the zero-current switching resonance DC/DC power supply; the other end of the capacitor C16 is connected with the anode of the diode D8, and the common terminal of the connection is connected with the common ground terminal of the control circuit of the zero-current switching resonance DC/DC power supply.

Further, the current mirror output voltage amplitude control circuit comprises a resistor R24, a resistor R25, a resistor R26, a diode D9, a capacitor C18, a capacitor C19 and a triode Q7; one end of the resistor R24 is connected with the current mirror circuit and the current output end Iin of the large dynamic current adjusting circuit; the other end of the resistor R24 is connected with one end of the capacitor C18 and the collector electrode of the triode Q7; the other end of the capacitor C18 is connected with one end of a resistor R25 and the base electrode of a triode Q7; the other end of the resistor R25 is connected with one end of the capacitor C19, one end of the resistor R26 and the cathode of the diode D9; the other end of the capacitor C19 is connected with a common ground end of a control circuit of the zero-current switching resonance DC/DC power supply; the anode of the diode D9 is connected with the emitter of the triode Q7, and the public end of the connection is connected with an electrical network port Vref1 of the multifunctional controllable power supply circuit; the other end of the resistor R26 is connected to the output port Ao of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit.

Further, the output current driving and dead time control circuit comprises a resistor R27, a resistor R28, a diode D10, a diode D11, a capacitor C20, a capacitor C21 and an integrated circuit IC6; one end of the resistor R27 is connected with the cathode of the diode D10, and the public end of the connection is connected with the output port Ao of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; one end of the resistor R28 is connected with the cathode of the diode D11, and the public end of the connection is connected with the output port Bo of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; the other end of the resistor R28 is connected with the anode of the diode D11, one end of the capacitor C21 and the 4 th pin of the integrated circuit IC6; the other end of the resistor R27 is connected with the anode of the diode D10, one end of the capacitor C20 and the 2 nd pin of the integrated circuit IC6; the other end of the capacitor C20 is connected with the other end of the capacitor C21 and the 3 rd pin of the integrated circuit IC6, and the public end of the connection is connected with the public grounding end of the control circuit of the zero-current switching resonance DC/DC power supply; the 5 th pin of the integrated circuit IC6 is connected with the output port Bout end of the control circuit of the zero-current switching resonance DC/DC power supply; the 7 th pin of the integrated circuit IC6 is connected with the output port Aout end of the control circuit of the zero current switch resonance DC/DC power supply; the 6 th pin of the integrated circuit IC6 is connected with the power input end Vic of the multifunctional controllable power supply circuit;

pins

1 and 8 of the integrated circuit IC6 are not electrically connected.

Compared with the prior art, the invention has the following technical effects:

1. the voltage of the Vi port is detected by the IC2 in the multifunctional controllable power supply circuit, so that the input voltage programmable undervoltage protection function can be set, and the output voltage overvoltage protection, overtemperature protection and other functions can also be set.

2. The result that the input end of the current mirror circuit can be controlled by the voltage stabilizing feedback signal Vfb with small range change is realized through the application of the junction field effect transistor Q5 in the current mirror circuit and the large dynamic current adjusting circuit and the setting of the grid bias voltage of the junction field effect transistor Q5.

3. The soft start control function of the control circuit of the zero-current switch resonance DC/DC power supply can be realized through the arrangement of the capacitor C10 and the resistor R18 in the soft start circuit.

4. In the multivibrator circuit and the pulse frequency synchronization and prohibition circuit, the integrated circuit IC5 and its peripheral circuits are used to realize several required functions as follows: (1) the basic function of the device and D4 reset the integrating circuits R19, R20 and C14 in a timing period are utilized to realize the function of a multivibrator circuit capable of outputting pulses with fixed width; (2) the functions that the pulse can not be triggered any more and the pulse with fixed width can be output in the timing period are realized through the arrangement of R21 and C15; (3) the function of modulating the oscillation frequency by the output current of the current mirror can be realized through the integrating circuits R19, R20 and C14 at the input end of the device, and the result that the output frequency can be adjusted by an external feedback signal within the range of 0.05 kHz-1.2 MHz is realized; (4) the multi-resonant circuit can be synchronized by external synchronous pulse to oscillate frequency through the setting of D3, and can realize the parallel application of a plurality of external power modules through the function, thereby realizing the result of power expansion; (5) the externally prohibited control function can also be realized by the setting of D3.

5. The zero current termination pulse signal input by the external GD port is controlled by the output pulse width adjusting circuit to terminate the timing pulse of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit in advance, and the switch of the main power MOSFEET is controlled to respond to the result that the zero current state needs to be turned off in real time, so that the function of turning off the main power MOSFEET switch device in the zero current state is realized.

6. The IC6 in the output current driving and dead time control circuit selects a special high-current MOSFET driving integrated circuit UCC27424 (or a circuit of the same type with the same index), has the capability of 4A output current and can ensure the normal switching speed of the MOSFET switching tube. And the dead time in the circuit protects the MOSFET power tube from being damaged due to simultaneous conduction.

7. All components used in the circuit are universal components, so that the circuit is stable and reliable in shelf life and wide in application.

In summary, compared with the prior art, the invention meets the functional requirement and technical requirement of the zero-current switching resonance DC/DC power supply by fusing seven sub-circuits with different functions, realizes high switching frequency (1 MHz) by using the full brick DC/DC power supply designed by the control circuit, realizes the advantages of zero-current on and off, high conversion efficiency, easy synchronous and parallel expansion of output power, good EMI characteristics, excellent dynamic response and the like by using the power switching device, meets the index requirement of foreign similar products, and can be completely compatible to replace the foreign similar products. The invention avoids patent limitation of an application specific integrated circuit, has low cost and wide application prospect, and can realize commercialization of a zero-current switching resonance DC/DC power supply.

Drawings

FIG. 1 is a multi-function controllable power supply circuit;

FIG. 2 is a schematic diagram of a current mirror circuit and a large dynamic current adjustment circuit;

FIG. 3 is a soft start circuit;

FIG. 4 is a multivibrator circuit and pulse frequency synchronization and disable circuit;

FIG. 5 is an output pulse width modulation circuit;

FIG. 6 is a circuit for controlling the amplitude of the output voltage of the current mirror;

fig. 7 is an output current drive and dead time control circuit.

The invention is further explained below with reference to the drawing and the specific embodiments.

Detailed Description

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and examples, and it is apparent that the described examples are only some, but not all, examples of the present invention.

As shown in fig. 1, the control circuit of the zero-current switching resonance DC/DC power supply provided by the invention comprises the following seven sub-circuits: the multi-functional controllable power supply circuit, the current mirror circuit and the large dynamic current adjusting circuit, the soft start circuit, the multivibrator circuit, the pulse frequency synchronizing and prohibiting circuit, the output pulse width adjusting circuit, the current mirror output voltage amplitude control circuit and the output current driving and dead time control circuit; the multifunctional controllable power supply circuit is used as a power supply and connected with other sub-circuits; the current mirror circuit and the large dynamic current adjusting circuit are connected with the soft start circuit, the multivibrator circuit, the pulse frequency synchronization and prohibition circuit and the current mirror output voltage amplitude control circuit; the multivibrator circuit and the pulse frequency synchronization and prohibition circuit are respectively connected with the output pulse width adjusting circuit, the current mirror output voltage amplitude control circuit, the output current driving and dead time control circuit.

As shown in fig. 1, the multifunctional controllable power supply circuit includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a silicon controlled device IC1, a reference source integrated circuit IC2, a reference source integrated circuit IC3, a reference source integrated circuit IC4, a diode D1, a diode D2, a triode Q1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, and a capacitor C6; the emitter of the triode Q1 is simultaneously connected with one end of a resistor R8 and the anode of a diode D1, and the connected common end (Vic) is used as a power input end (Vic) of the multifunctional controllable power supply circuit and is connected with the power input end of the control circuit of the zero-current switch resonance DC/DC power supply; the collector of the triode Q1 is simultaneously connected with the anode of the capacitor C4, one end of the resistor R11, the anode of the diode D2 and the input end of the reference source integrated circuit IC4, and the connected common end (VDD) is used as a node of the power output of the multifunctional controllable power supply circuit to be connected with other sub-circuits; the base electrode of the triode Q1 is simultaneously connected with the other end of the resistor R8 and one end of the resistor R9; the output end of the reference source integrated circuit IC4 is connected with one end of a capacitor C6, and the connected common end (5V) is used as a 5V voltage output end of the multifunctional controllable power supply circuit to be supplied to other sub-circuits; the other end of the resistor R11 is connected with one end of the capacitor C5, the 1 st pin and the 2 nd pin of the reference source integrated circuit IC3, and the connected common end (Vref 1) is used as the Vref1 output end (electric network port) of the multifunctional controllable power supply circuit to be provided for the current mirror output voltage amplitude control circuit; the 2 nd pin of the reference source integrated circuit IC2 is simultaneously connected with the other end of the resistor R9 and one end of the capacitor C3; the 1 st pin of the reference source integrated circuit IC2 is simultaneously connected with one end of a resistor R5, one end of a resistor R6, one end of a resistor R10 and the other end of a capacitor C3; the other end of the resistor R10 is connected with the cathode of the diode D2; the 3 rd pin of the reference source integrated circuit IC2 is connected with the other end of the resistor R6, one end of the resistor R3, one end of the resistor R1, one end of the capacitor C2, the other end of the capacitor C6, the other end of the capacitor C5, the negative electrode of the capacitor C4, the 2 nd pin of the silicon controlled device IC1, the 3 rd pin of the reference source integrated circuit IC3 and the grounding end of the reference source integrated circuit IC4, and the connected common end is used as a grounding common end of the multifunctional controllable power supply circuit and the control circuit of the zero-current switch resonance DC/DC power supply; the other end of the resistor R5 is connected with one end of the resistor R4; the cathode of the diode D1 is connected with one end of a resistor R7; the 1 st pin of the silicon controlled device IC1 is simultaneously connected with the other end of the resistor R4 and the other end of the resistor R7, and the connected common end (Vi) is used as a voltage input Vi port of the multifunctional controllable power supply circuit; the 3 rd pin of the silicon controlled device IC1 is simultaneously connected with the other end of the capacitor C2, the other end of the resistor R3 and one end of the resistor R2; the other end of the resistor R2 is connected with the other end of the resistor R1 and the other end of the capacitor C1, and the connected common end is used as an input RT/OV port of the multifunctional controllable power supply circuit.

Under the above technical scheme, the input voltage of the Vi port is detected through the IC2, when the input voltage of the Vi port is larger than the threshold voltage Vith1 of Vi (= 2.5V (R4+R5+R6)/R6), Q1 is conducted, an external Vic power supply is connected to the VDD network node, and power is provided for other sub-circuits; when the input voltage Vi is smaller than the threshold voltage Vith2 of Vith (=Vith 1-1.2V), Q1 is turned off, and VDD=0V, other sub-circuits are powered off; the function of D2 in the circuit is to provide a hysteresis (=vith1-vith2=1.2v) design for the threshold voltage Vith1, which allows the circuit to be kept stable during Q1 switching without oscillation. The design can be used as the undervoltage detection control of the input voltage in the design of the DC/DC power supply, and forms the undervoltage protection function of the input voltage. In addition, when the signal received through the RT/OV port (used as an output overvoltage and overtemperature signal or other needed signals in the design of a DC/DC power supply) is larger than the 3 rd pin trigger voltage of the silicon controlled device IC1, the control IC1 is conducted to form a Vi voltage under-voltage state, and the power supply of other sub-circuits is turned off, so that a protection function is realized. In addition, the circuit generates two voltage sources of 2.5V (Vref 1) and 5.0V through the IC3 and the IC4 respectively to provide needed voltages for other sub-circuits.

Wherein the capacitance of the capacitor C1, the capacitor C2 and the capacitor C5 is 0.1uF/50V, the capacitance of the capacitor C3 is 180pF/50V, the capacitance of the capacitor C4 is 10uF/16V, the capacitance of the capacitor C6 is 0.22uF/50V, the resistance of the resistor R1 is 2kΩ, the resistance of the resistor R2 is 4.3 k Ω, the resistance of the resistor R3 and the resistor R8 is 1 k Ω, the resistance of the resistor R4 is 1.5 k Ω, the resistance of the resistor R5 is 20 k Ω, the resistance of the resistor R6 is 5.1 k omega, the resistance of the resistor R7 is 3 k omega, the resistance of the resistor R9 is 3.6 k omega, the resistance of the resistor R10 is 200 k omega, the resistance of the resistor R11 is 6.2 k omega, the types of diodes D1 and D2 are IN4148WS, the type of the silicon controlled device IC1 is MCR100-8, the types of the reference source integrated circuits IC2 and IC3 are TL431, the type of the reference source integrated circuit IC4 is LM7805, and the type of the triode Q1 is BT2907.

As shown in fig. 2, the current mirror circuit and the large dynamic current adjusting circuit include a resistor R12, a resistor R13, a resistor R14, a resistor R15, a resistor R16, a transistor Q2, a transistor Q3, a transistor Q4, a junction field effect transistor Q5, a capacitor C7, a capacitor C8, and a capacitor C9; wherein the emitter of the triode Q2 is connected with the emitter of the triode Q3, and the public end of the connection is connected with an output node (VDD) of the multifunctional controllable power supply circuit; the base electrode of the triode Q2 is connected with the base electrode of the triode Q3, the collector electrode of the triode Q3 and the emitter electrode of the triode Q4; the collector of the triode Q2 is simultaneously connected with the base of the triode Q4, one end of a resistor R12, one end of a resistor R13 and one end of a capacitor C8; the other end of the resistor R12 is connected with one end of the resistor R14, one end of the capacitor C7, one end of the capacitor C9 and the 3 rd pin of the junction field effect transistor Q5, and the connected common end is used as an input port (FB) of the current mirror circuit and the large dynamic current regulating circuit and is used as a feedback signal input end of the control circuit of the zero current switching resonance DC/DC power supply; the 1 st pin of the junction field effect transistor Q5 is connected with the other end of the resistor R13; the 2 nd pin of the junction field effect transistor Q5 is connected with one end of a resistor R15, one end of a resistor R16 and the other end of a capacitor C9; the other end of the resistor R15 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the collector of the triode Q4 is connected with the other end of the capacitor C8, and the connected common terminal is used as a current output terminal (Iin) of the current mirror circuit and the large dynamic current adjusting circuit to be provided for other sub-circuits. The other end of the capacitor C7 is connected with the other end of the resistor R14 and the other end of the resistor R16, and the connected common terminal is connected with the grounding common terminal of the control circuit of the zero-current switching resonance DC/DC power supply.

Under the above technical scheme, the R15, R16 and 5V voltage sources provide the bias voltage Vg for the 2 nd pin of the junction field effect transistor Q5, and the on-resistance Rq5 of the junction field effect transistor Q5 is controlled by using the voltage difference Vgs between the bias voltage Vg and the voltage Vfb of the feedback signal port FB; since the triodes Q2 and Q3 are current mirror circuits, the current relationship in the collectors of the triodes Q2, Q3 and Q4 is obtained according to the characteristics of the current mirror circuits: iq2=iq3=iq4=iin= (VDD-1.4-Vfb)/r12+ (VDD-1.4-Vfb)/(r13+rq5), and thus the magnitude of the Iin current can be controlled by controlling the magnitude of the voltage Vfb of the feedback signal port FB. In an actual DC/DC power supply design, the variation range of the voltage-stabilizing feedback signal Vfb is not large, but the variation range of the on-resistance Rq5 of the junction field effect transistor Q5 can be large, so that the variation range of the current Iin controlled by the Vfb is large and can reach 1000 times of the range, and the characteristic can be utilized to obtain the result that the voltage-stabilizing feedback signal Vfb with small range variation can control a large dynamic current adjustment range.

The capacitance value of the capacitor C7 is 100pF/50V, the capacitance value of the capacitor C8 is 390pF/50V, the capacitance value of the capacitor C9 is 47nF/50V, the resistance value of the resistor R12 is 30 k omega, the resistance value of the resistor R13 is 6.2 k omega, the resistance value of the resistor R14 is 1.5 k omega, the resistance value of the resistor R15 is 3.3 k omega, the resistance value of the resistor R16 is 7.5 k omega, the types of triodes Q2 and Q3 are DT3906, the type of the triode Q4 is BT2907, and the type of the junction field effect transistor Q5 is MMBF5484.

As shown in fig. 3, the soft start circuit includes a resistor R17, a resistor R18, a transistor Q6, a capacitor C10, a capacitor C11, and a capacitor C12; one end of the capacitor C10 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the capacitor C10 is connected with one end of the resistor R17 and one end of the resistor R18; the other end of the resistor R18 is connected with one end of the capacitor C11 and the base electrode of the triode Q6; the collector of the triode Q6 is connected with one end of a capacitor C12, and the public end of the connection is connected with the current output end (Iin) of the current mirror circuit and the large dynamic current regulating circuit; the other end of the resistor R17 is connected with the other end of the capacitor C11, the emitter of the triode Q6 and the other end of the capacitor C12, and the common end of the connection is connected with the grounding common end of the control circuit of the zero-current switching resonance DC/DC power supply.

Under the above technical scheme, when 5V voltage is established, the CR differentiating circuit composed of the capacitor C10 and the resistor R17 makes the triode Q6 conduct to control the output current Iin signal of the current mirror, and as the voltage on the capacitor C10 increases, the triode Q6 gradually exits from the conducting state until completely turned off. In this process, the current through the triode Q6 gradually decreases from the maximum Iin current to zero, so that the current Iin output from the current mirror flows to the multivibrator circuit and the pulse frequency synchronization and disabling circuit after passing through the soft start control circuit, and the current on the input resistor R19 becomes a controlled increasing starting phenomenon from zero until the original value of Iin current is recovered.

The capacitance value of the capacitor C10 is 33nF/50V, the capacitance value of the capacitor C11 is 100pF/50V, the capacitance value of the capacitor C12 is 390pF/50V, the resistance value of the resistor R17 is 200 k omega, the resistance value of the resistor R18 is 100 k omega, and the model of the triode Q6 is ST2222.

As shown in fig. 4, the multivibrator circuit and the pulse frequency synchronization and prohibition circuit include a resistor R19, a resistor R20, a resistor R21, a diode D3, a diode D4, a capacitor C13, a capacitor C14, a capacitor C15, and an integrated circuit IC5; one end of the resistor R19 is connected with a current output end (Iin) of the current mirror circuit and the large dynamic current adjusting circuit; the other end of the resistor R19 is connected with one end of the resistor R20 and the anode of the diode D3; the cathode of the diode D3 is connected with a synchronous port (SYNC) of a control circuit of the zero-current switching resonance DC/DC power supply; the other end of the resistor R20 is connected with the anode of the diode D4, one end of the capacitor C14 and the 2 nd pin of the integrated circuit IC5; the cathode of the diode D4 is connected with the output port (Bout) of the control circuit of the zero-current switching resonance DC/DC power supply; one end of the capacitor C13 is simultaneously connected with one end of the resistor R21, the 3 rd pin of the integrated circuit IC5 and the 16 th pin of the integrated circuit IC5, and the public end of the connection is connected with the 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the resistor R21 is connected with one end of the capacitor C15 and the 15 th pin of the integrated circuit IC5, and the public end of the connection is used as the (RC) network end to be connected with the (RC) network end of the output pulse width adjusting circuit; the other end of the capacitor C15 is connected with the other end of the capacitor C14, the other end of the capacitor C13, the 1 st pin of the integrated circuit IC5, the 8 th pin of the integrated circuit IC5 and the 14 th pin of the integrated circuit IC5, and the common terminal of the connection is connected with the common ground terminal of the control circuit of the zero-current switching resonance DC/DC power supply. The 13 th pin of the integrated circuit IC5 is used as an output port (Ao) of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit to be connected with an output current driving part; the 4 th pin of the integrated circuit IC5 is used as an output port (Bo) of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit to be connected with an output current driving part;

Under the technical scheme, the integrated circuit IC5 is a high-speed CMOS monostable multivibrator digital integrated circuit, C15 is a timing capacitor with the pulse width output by the IC5, R21 is a timing resistor part with the pulse width output by the IC5, and the sizes of the timing capacitor and the timing resistor determine the maximum width Ton of the output pulse of the IC 5; c14 is the integral capacitance of the input trigger end of the IC5, R19 and R20 are the integral resistances of the input trigger end of the IC5, when the Iin current charges C14 to the threshold voltage of the input trigger end of the IC5 through the resistances R19 and R20, the 13 th pin of the IC5, namely the Ao end outputs a pulse with the maximum width Ton timed by C15 and R21, and the 4 th pin of the IC5, namely the output pulse of the Bo end and the output pulse of the 13 th pin are in 180-degree complementary relation. While the Ao terminal outputs the timing high-level Ton pulse, the low-level pulse of the Bo terminal completely discharges the C14 capacitor through D4 via the low-level pulse (Bout) output from the following driving circuit. When the end Ao terminal of the timing pulse outputted from the IC5 becomes low, the Bo terminal also becomes high, the Bout terminal of the following driving circuit also becomes high, and D4 is turned off, so that Iin starts charging C14 again through R19 and R20, thus forming an oscillating circuit in which the Ao terminal outputs a fixed pulse width. C14 starts charging until the charging voltage reaches the threshold voltage of the IC5 input trigger terminal, and if the charging time is Toff and the time of outputting the timing pulse width is Ton, the period of the IC5 output oscillation pulse is: t=ton+toff. From this relationship, it can be derived: the period T of the oscillation pulse is inversely proportional to the magnitude of the charging current Iin, that is: the frequency of the oscillation pulse is proportional to the magnitude of the charging current Iin. In addition, the diode D3 is connected to an external pulse frequency synchronization and prohibition circuit port (SYNC), and when the port (SYNC) is connected to a low level (less than 0.2V), the input end current of the multivibrator circuit is embedded below 1V, the IC5 cannot form a trigger signal, the multivibrator of the IC5 is stopped, the Ao port has no pulse output, and the Ao port output pulse prohibition function is formed. When a port (SYNC) applies a pulse signal Fsync satisfying (minimum pulse width, amplitude, and frequency range) requirements, the oscillating frequency of the multivibrator circuit will change in synchronization with Fsync, forming the function of synchronizing the internal oscillating frequency with the externally applied frequency Fsync.

The capacitance of the capacitor C13 is 104/50V, the capacitance of the capacitor C14 is 108pF/50V, the capacitance of the capacitor C15 is 100pF/50V, the resistance of the resistor 19 is 2k omega, the resistance of the resistor R20 is 1 k omega, the resistance of the resistor R21 is 8.2k omega, the types of diodes D3 and D4 are IN4148WS, and the type of the integrated circuit IC5 is 74HC221.

As shown in fig. 5, the output pulse width adjustment circuit includes a resistor R22, a resistor R23, a diode D5, a diode D6, a diode D7, a diode D8, a capacitor C16, and a capacitor C17; one end of the resistor R23 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the resistor R23 is connected with one end of the resistor R22, one end of the capacitor C16 and the cathode of the diode D6; the anode of the diode D6 is connected with the other end of the resistor R22, the anode of the diode D5, the anode of the diode D7, the cathode of the diode D8 and one end of the capacitor C17; the cathode of the diode D5 is connected with the (RC) network end of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; the cathode of the diode D7 is connected with an output port (Aout) of the dead time control circuit; the other end of the capacitor C17 is connected to the input port (GD) of the control circuit of the zero current switching resonant DC/DC power supply of the invention. The other end of the capacitor C16 is connected with the anode of the diode D8, and the common terminal of the connection is connected with the common ground terminal of the control circuit of the zero-current switching resonance DC/DC power supply.

Under the technical scheme, a zero current termination pulse signal input from the GD port externally charges a timing capacitor C15 of the multivibrator circuit and the pulse frequency synchronization and inhibition circuit through C17 and D5, so that the timing time acceleration of the multivibrator circuit and the pulse frequency synchronization and inhibition circuit is finished, and the output pulse of the Ao port of the multivibrator circuit is terminated in advance. The function of D6 and C16 is to block the amplitude of the externally input termination pulse so that the positive voltage of D5 does not exceed 5.5V; the function of D8 is that the positive voltage of the block D5 is not lower than-0.5V; d7 is used for preventing noise signals of an external GD terminal in a low level period from interfering with timing signals of the multivibrator circuit; d5 is used for isolating the electric signal by utilizing the unidirectional conductivity of the diode, and only the zero current termination pulse signal passes through. Meanwhile, the negative temperature coefficient of the D5 diode is used for compensating the positive temperature coefficient of the IC5 timing circuit, so that the temperature coefficient of the timing width of the output pulse of the compensated Ao port is smaller.

Wherein, the capacitance value of the capacitor C16 is 0.1uF/50V, the capacitance value of the capacitor C17 is 51pF/50V, the resistance value of the resistor R22 is 10 k omega, the resistance value of the resistor R23 is 1 k omega, the types of the diodes D5 and D8 are IN4148WS, and the types of the diodes D6 and D7 are BAW56W.

As shown in fig. 6, the current mirror output voltage amplitude control circuit includes a resistor R24, a resistor R25, a resistor R26, a diode D9, a capacitor C18, a capacitor C19, and a triode Q7; one end of the resistor R24 is connected with a current output end (Iin) of the current mirror circuit and the large dynamic current adjusting circuit; the other end of the resistor R24 is connected with one end of the capacitor C18 and the collector electrode of the triode Q7; the other end of the capacitor C18 is connected with one end of the resistor R25 and the base electrode of the triode Q7; the other end of the resistor R25 is connected with one end of the capacitor C19, one end of the resistor R26 and the cathode of the diode D9; the other end of the capacitor C19 is connected with a common ground end of a control circuit of the zero-current switching resonance DC/DC power supply; the anode of the diode D9 is connected with the emitter of the triode Q7, and the public end of the connection is connected with an electric network port (Vref 1) of the multifunctional controllable power supply circuit; the other end of the resistor R26 is connected to an output port (Ao) of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit.

Under the above technical scheme, when Ao outputs high level, triode Q7 is turned on through the integration delay of R26, C19, so that Iin current flowing to multivibrator circuit is shunted, and flows into Vref1 through current limiting resistors R24 and Q7, so as to control voltage amplitude generated by Iin current at the input end of multivibrator circuit not to be too high, and ensure that the input end of integrated circuit IC5 is not damaged. The size of the current limiting resistor R24 can control the shunt proportion of Iin current, the resistor R25 is the base current limiting resistor of the triode Q7, and the diode D9 provides a bias voltage for the base of the triode Q7 so as to improve the response speed of the triode Q7.

The capacitance of the capacitor C18 is 103/50V, the capacitance of the capacitor C19 is 473/50V, the resistance of the resistor R24 is 3 k omega, the resistance of the resistor R25 is 5.1 k omega, the resistance of the resistor R26 is 3.6 k omega, the diode D9 is IN4148WS, and the triode Q7 is ST2222.

As shown in fig. 7, the output current driving and dead time control circuit includes a resistor R27, a resistor R28, a diode D10, a diode D11, a capacitor C20, a capacitor C21, and an integrated circuit IC6; one end of the resistor R27 is connected with the cathode of the diode D10, and the public end of the connection is connected with the output port (Ao) of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; one end of the resistor R28 is connected with the cathode of the diode D11, and the public end of the connection is connected with an output port (Bo) of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; the other end of the resistor R28 is connected with the anode of the diode D11, one end of the capacitor C21 and the 4 th pin of the integrated circuit IC6; the other end of the resistor R27 is connected with the anode of the diode D10, one end of the capacitor C20 and the 2 nd pin of the integrated circuit IC6; the other end of the capacitor C20 is connected with the other end of the capacitor C21 and the 3 rd pin of the integrated circuit IC6, and the common end of the connection is connected with the grounding end of the whole control circuit; the 5 th pin of the integrated circuit IC6 is connected with the output port (Bout) end of the control circuit of the zero-current switching resonance DC/DC power supply; the 7 th pin of the integrated circuit IC6 is connected with the output port (Aout) end of the control circuit of the zero current switching resonance DC/DC power supply; the 6 th pin of the integrated circuit IC6 is connected with a power input end (Vic) of the multifunctional controllable power supply circuit; pins 1 and 8 of the integrated circuit IC6 are not electrically connected.

Under the above technical scheme, the IC6 is a dedicated high-current MOSFET driving integrated circuit UCC27424 (or a circuit of the same type with the same index), and functions to amplify the current of the pulse output signals Ao and Bo of the IC5 and output the amplified pulse output signals Aout and Bout; in the design, the rising edge of the output pulse is delayed by the two complementary pulses output by the IC5 through the corresponding RC (R27 and C20, R28 and C21) integrating circuits, so that the two complementary pulses output by the IC6 are respectively ensured to have a certain dead time, the size of the dead time is controlled by the size of the RC (R27 and C20, R28 and C21) integrating circuits, and the setting of the dead time ensures that the conduction of two MOSFET power tubes in the zero-current switching resonance DC/DC power supply has a certain dead time, and the condition that the two MOSFET power tubes are simultaneously conducted is prevented.

The capacitance value of the capacitor C20 is 22pF/50V, the capacitance value of the capacitor C21 is 51pF/50V, the resistance values of the resistors R27 and R28 are 1 k omega, the types of the diodes D10 and D11 are RB751V, and the type of the integrated circuit IC6 is UCC27424.

The zero-current switch resonance DC/DC power supply designed by the technical scheme of the invention realizes the working state of zero-current turn-off of the main power device in the full range of input voltage. The switching frequency of the zero-current switching resonance DC/DC power supply is regulated to be changed within the range of 0.05 kHz-1.2 MHz through the feedback signal of the output voltage, so that the adjustment of the output power is realized, and the stability of the output voltage is also realized. The overvoltage protection and the overtemperature protection of the output voltage set by the control circuit of the invention work normally, thereby achieving the purpose of protection. Meanwhile, the DC/DC power supplies of the same model adopting the zero-current switch resonance control technology are synchronously arranged through the switching frequency, so that the functions of equalizing output current and expanding output power can be realized easily.

While the invention has been described with respect to the preferred embodiments, it will be understood by those skilled in the art that the present invention is not limited thereto, and that any changes or substitutions without the inventive faculty may be made without departing from the scope of the invention.

Claims

1. The control circuit of the zero-current switching resonance DC/DC power supply is characterized by comprising the following seven sub-circuits: the multi-functional controllable power supply circuit, the current mirror circuit and the large dynamic current adjusting circuit, the soft start circuit, the multivibrator circuit, the pulse frequency synchronizing and prohibiting circuit, the output pulse width adjusting circuit, the current mirror output voltage amplitude control circuit and the output current driving and dead time control circuit; the multifunctional controllable power supply circuit is used as a power supply and connected with other sub-circuits; the current mirror circuit and the large dynamic current adjusting circuit are connected with the soft start circuit, the multivibrator circuit, the pulse frequency synchronization and prohibition circuit and the current mirror output voltage amplitude control circuit; the multivibrator circuit and the pulse frequency synchronization and prohibition circuit are respectively connected with the output pulse width adjusting circuit, the current mirror output voltage amplitude control circuit, the output current driving and dead time control circuit.

2. The control circuit of the zero current switching resonant DC/DC power supply of claim 1, wherein the multifunctional controllable power supply circuit comprises a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a thyristor device IC1, a reference source integrated circuit IC2, a reference source integrated circuit IC3, a reference source integrated circuit IC4, a diode D1, a diode D2, a triode Q1, a capacitor C2, a capacitor C3, a capacitor C4, a capacitor C5, and a capacitor C6; the emitter of the triode Q1 is simultaneously connected with one end of a resistor R8 and the anode of a diode D1, and the connected common end is used as a power input end Vic of a multifunctional controllable power supply circuit and is connected with the power input end of a control circuit of the zero-current switch resonance DC/DC power supply; the collector of the triode Q1 is simultaneously connected with the anode of the capacitor C4, one end of the resistor R11, the anode of the diode D2 and the input end of the reference source integrated circuit IC4, and the connected common end VDD is used as a node of the power supply output of the multifunctional controllable power supply circuit; the base electrode of the triode Q1 is simultaneously connected with the other end of the resistor R8 and one end of the resistor R9; the output end of the reference source integrated circuit IC4 is connected with one end of a capacitor C6, and the connected common end is used as a 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the resistor R11 is connected with one end of the capacitor C5, the 1 st pin and the 2 nd pin of the reference source integrated circuit IC3, and the connected common end is used as an electrical network port Vref1 of the multifunctional controllable power supply circuit to be provided for the current mirror output voltage amplitude control circuit; the 2 nd pin of the reference source integrated circuit IC2 is simultaneously connected with the other end of the resistor R9 and one end of the capacitor C3; the 1 st pin of the reference source integrated circuit IC2 is simultaneously connected with one end of a resistor R5, one end of a resistor R6, one end of a resistor R10 and the other end of a capacitor C3; the other end of the resistor R10 is connected with the cathode of the diode D2; the 3 rd pin of the reference source integrated circuit IC2 is connected with the other end of the resistor R6, one end of the resistor R3, one end of the resistor R1, one end of the capacitor C2, the other end of the capacitor C6, the other end of the capacitor C5, the negative electrode of the capacitor C4, the 2 nd pin of the silicon controlled device IC1, the 3 rd pin of the reference source integrated circuit IC3 and the grounding end of the reference source integrated circuit IC4, and the connected common end is used as a grounding common end of a multifunctional controllable power supply circuit and a control circuit of the zero-current switching resonance DC/DC power supply; the other end of the resistor R5 is connected with one end of the resistor R4; the cathode of the diode D1 is connected with one end of a resistor R7; the 1 st pin of the silicon controlled device IC1 is simultaneously connected with the other end of the resistor R4 and the other end of the resistor R7, and the connected common end is used as a voltage input Vi port of the multifunctional controllable power supply circuit; the 3 rd pin of the silicon controlled device IC1 is simultaneously connected with the other end of the capacitor C2, the other end of the resistor R3 and one end of the resistor R2; the other end of the resistor R2 is connected with the other end of the resistor R1 and the other end of the capacitor C1, and the connected common end is used as an input RT/OV port of the multifunctional controllable power supply circuit.

3. The control circuit of the zero current switching resonant DC/DC power supply of claim 2, wherein the current mirror circuit and the large dynamic current adjustment circuit comprise a resistor R12, a resistor R13, a resistor R14, a resistor R15, a resistor R16, a transistor Q2, a transistor Q3, a transistor Q4, a junction field effect transistor Q5, a capacitor C7, a capacitor C8, and a capacitor C9; the emitter of the triode Q2 is connected with the emitter of the triode Q3, and the public end of the connection is connected with an output node VDD of the multifunctional controllable power supply circuit; the base electrode of the triode Q2 is connected with the base electrode of the triode Q3, the collector electrode of the triode Q3 and the emitter electrode of the triode Q4; the collector of the triode Q2 is simultaneously connected with the base of the triode Q4, one end of a resistor R12, one end of a resistor R13 and one end of a capacitor C8; the other end of the resistor R12 is connected with one end of the resistor R14, one end of the capacitor C7, one end of the capacitor C9 and the 3 rd pin of the junction field effect transistor Q5, and the connected common end is used as an input port FB of the current mirror circuit and the large dynamic current regulating circuit and is used as a feedback signal input end of the control circuit of the zero current switching resonance DC/DC power supply; the 1 st pin of the junction field effect transistor Q5 is connected with the other end of the resistor R13; the 2 nd pin of the junction field effect transistor Q5 is connected with one end of a resistor R15, one end of a resistor R16 and the other end of a capacitor C9; the other end of the resistor R15 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the collector of the triode Q4 is connected with the other end of the capacitor C8, and the connected common end is used as a current output end Iin of the current mirror circuit and the large dynamic current regulating circuit; the other end of the capacitor C7 is connected with the other end of the resistor R14 and the other end of the resistor R16, and the common end of the connection is connected with the common ground end of the control circuit of the zero-current switching resonance DC/DC power supply.

4. The control circuit of the zero current switching resonant DC/DC power supply of claim 3, wherein the soft start circuit comprises a resistor R17, a resistor R18, a transistor Q6, a capacitor C10, a capacitor C11 and a capacitor C12; one end of the capacitor C10 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the capacitor C10 is connected with one end of the resistor R17 and one end of the resistor R18; the other end of the resistor R18 is connected with one end of the capacitor C11 and the base electrode of the triode Q6; the collector of the triode Q6 is connected with one end of a capacitor C12, and the public end of the connection is connected with a current mirror circuit and a current output end Iin of the large dynamic current regulating circuit; the other end of the resistor R17 is simultaneously connected with the other end of the capacitor C11, the emitter of the triode Q6 and the other end of the capacitor C12, and the common end of the connection is connected with the common ground end of the control circuit of the zero-current switching resonance DC/DC power supply.

5. The control circuit of the zero current switching resonant DC/DC power supply of claim 4, wherein the multivibrator circuit and the pulse frequency synchronization and disable circuit comprise resistor R19, resistor R20, resistor R21, diode D3, diode D4, capacitor C13, capacitor C14, capacitor C15, and integrated circuit IC5; one end of the resistor R19 is connected with the current mirror circuit and the current output end Iin of the large dynamic current adjusting circuit; the other end of the resistor R19 is connected with one end of the resistor R20 and the anode of the diode D3; the cathode of the diode D3 is connected with a synchronous port SYNC of a control circuit of the zero-current switching resonance DC/DC power supply; the other end of the resistor R20 is connected with the anode of the diode D4, one end of the capacitor C14 and the 2 nd pin of the integrated circuit IC5; the cathode of the diode D4 is connected with an output port Bout of a control circuit of the zero-current switching resonance DC/DC power supply; one end of the capacitor C13 is simultaneously connected with one end of the resistor R21, the 3 rd pin of the integrated circuit IC5 and the 16 th pin of the integrated circuit IC5, and the public end of the connection is connected with the 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the resistor R21 is connected with one end of the capacitor C15 and the 15 th pin of the integrated circuit IC5, and the connected common end is used as an RC network end to be connected with an output pulse width adjusting circuit; the other end of the capacitor C15 is connected with the other end of the capacitor C14, the other end of the capacitor C13, the 1 st pin of the integrated circuit IC5, the 8 th pin of the integrated circuit IC5 and the 14 th pin of the integrated circuit IC5, and the public end of the connection is connected with the public grounding end of the control circuit of the zero-current switch resonance DC/DC power supply; the 13 th pin of the integrated circuit IC5 is used as an output port Ao of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; the 4 th pin of the integrated circuit IC5 serves as the output port Bo of the multivibrator circuit and the pulse frequency synchronization and disable circuit.

6. The control circuit of the zero current switching resonant DC/DC power supply of claim 5, wherein the output pulse width modulation circuit comprises a resistor R22, a resistor R23, a diode D5, a diode D6, a diode D7, a diode D8, a capacitor C16, and a capacitor C17; one end of the resistor R23 is connected with a 5V voltage output end of the multifunctional controllable power supply circuit; the other end of the resistor R23 is connected with one end of the resistor R22, one end of the capacitor C16 and the cathode of the diode D6; the anode of the diode D6 is connected with the other end of the resistor R22, the anode of the diode D5, the anode of the diode D7, the cathode of the diode D8 and one end of the capacitor C17; the cathode of the diode D5 is connected with the RC network end of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; the cathode of the diode D7 is connected with an output port Aout of the dead time control circuit; the other end of the capacitor C17 is connected with an input port GD of a control circuit of the zero-current switching resonance DC/DC power supply; the other end of the capacitor C16 is connected with the anode of the diode D8, and the common terminal of the connection is connected with the common ground terminal of the control circuit of the zero-current switching resonance DC/DC power supply.

7. The control circuit of the zero current switching resonant DC/DC power supply of claim 6, wherein the current mirror output voltage amplitude control circuit comprises a resistor R24, a resistor R25, a resistor R26, a diode D9, a capacitor C18, a capacitor C19, and a transistor Q7; one end of the resistor R24 is connected with the current mirror circuit and the current output end Iin of the large dynamic current adjusting circuit; the other end of the resistor R24 is connected with one end of the capacitor C18 and the collector electrode of the triode Q7; the other end of the capacitor C18 is connected with one end of a resistor R25 and the base electrode of a triode Q7; the other end of the resistor R25 is connected with one end of the capacitor C19, one end of the resistor R26 and the cathode of the diode D9; the other end of the capacitor C19 is connected with a common ground end of a control circuit of the zero-current switching resonance DC/DC power supply; the anode of the diode D9 is connected with the emitter of the triode Q7, and the public end of the connection is connected with an electrical network port Vref1 of the multifunctional controllable power supply circuit; the other end of the resistor R26 is connected to the output port Ao of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit.

8. The control circuit of the zero current switching resonant DC/DC power supply of claim 7, wherein the output current driving and dead time control circuit comprises a resistor R27, a resistor R28, a diode D10, a diode D11, a capacitor C20, a capacitor C21, and an integrated circuit IC6; one end of the resistor R27 is connected with the cathode of the diode D10, and the public end of the connection is connected with the output port Ao of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; one end of the resistor R28 is connected with the cathode of the diode D11, and the public end of the connection is connected with the output port Bo of the multivibrator circuit and the pulse frequency synchronization and prohibition circuit; the other end of the resistor R28 is connected with the anode of the diode D11, one end of the capacitor C21 and the 4 th pin of the integrated circuit IC6; the other end of the resistor R27 is connected with the anode of the diode D10, one end of the capacitor C20 and the 2 nd pin of the integrated circuit IC6; the other end of the capacitor C20 is connected with the other end of the capacitor C21 and the 3 rd pin of the integrated circuit IC6, and the public end of the connection is connected with the public grounding end of the control circuit of the zero-current switching resonance DC/DC power supply; the 5 th pin of the integrated circuit IC6 is connected with the output port Bout end of the control circuit of the zero-current switching resonance DC/DC power supply; the 7 th pin of the integrated circuit IC6 is connected with the output port Aout end of the control circuit of the zero current switch resonance DC/DC power supply; the 6 th pin of the integrated circuit IC6 is connected with the power input end Vic of the multifunctional controllable power supply circuit; pins 1 and 8 of the integrated circuit IC6 are not electrically connected.