CN214154342U

CN214154342U - Magnetic isolation wide-range input voltage stabilizing circuit

Info

Publication number: CN214154342U
Application number: CN202022910710.1U
Authority: CN
Inventors: 黄国兵; 张冰; 徐亦祥
Original assignee: Shenzhen Zhenhua Microelectronics Co Ltd
Current assignee: Shenzhen Zhenhua Microelectronics Co Ltd
Priority date: 2020-12-04
Filing date: 2020-12-04
Publication date: 2021-09-07
Anticipated expiration: 2030-12-04

Abstract

The utility model provides a wide range input voltage stabilizing circuit is kept apart to magnetism, including first flyback synchronous rectifier module, second flyback synchronous rectifier module, voltage current feedback module, PWM control module, isolation driving transformer, drive module, input undervoltage protection module, elementary auxiliary power supply module and secondary auxiliary power supply module. The utility model discloses a topology is kept apart to crisscross parallelly connected flyback synchronous rectification magnetism, realizes power average distribution, and the vice limit magnetism in source limit is kept apart, reduces input/output filter device, improves the device reliability, realizes miniaturizing.

Description

Magnetic isolation wide-range input voltage stabilizing circuit

Technical Field

The utility model belongs to the technical field of the aviation power supply technique and specifically relates to a realize magnetic isolation wide range input voltage stabilizing circuit.

Background

The switching power supply topology is a topology structure widely applied in the field of electronic technology, the further development of the electronic technology puts new requirements on the performance of switching power supply topology devices in all aspects, particularly the technical field of aviation power supplies, the requirements on the volume, the reliability and the performance of power supply products are very high, and the conventional switching power supply topology has great defects in the aspects of realizing magnetic isolation, wide voltage input and device miniaturization.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem, the utility model provides a magnetism keeps apart wide region input voltage stabilizing circuit adopts crisscross parallelly connected flyback synchronous rectification magnetism isolation topology, realizes power average distribution, and source limit and vice limit magnetism are kept apart, and PWM control module is located the power vice limit, and direct sampling point presses the comparison, need not the opto-coupler, reduces input/output filter device, realizes that the device is miniaturized.

The utility model discloses a following technical scheme realizes:

the utility model provides a magnetic isolation wide range input voltage stabilizing circuit, a serial communication port, fly back synchronous rectification module, second to fly back synchronous rectification module, voltage current feedback module, PWM control module, isolation driving transformer, drive module, input undervoltage protection module including first, elementary auxiliary power source module and secondary auxiliary power source module, first fly back synchronous rectification module with the second fly back synchronous rectification module structure the same and input and the equal parallel connection of output between them, voltage current feedback module connects respectively first fly back synchronous rectification module's output the second fly back synchronous rectification module's output with PWM control module, PWM control module connects respectively first fly back synchronous rectification module with the second fly back synchronous rectification module vice switching device, and pass through isolation driving transformer with drive module connects respectively first fly back synchronous rectification module and PWM control module The input undervoltage protection module is respectively connected with the driving module and the primary auxiliary power module, the primary auxiliary power module is connected with the isolation driving transformer, and the secondary auxiliary power module is respectively connected with the PWM control module, the voltage and current feedback module and the isolation driving transformer.

Further, the magnetic isolation wide-range input voltage stabilizing circuit is characterized in that the first flyback synchronous rectification module comprises a first inductor, a second inductor, a first capacitor, a second capacitor, a third capacitor, a first MOS transistor, a second MOS transistor, a first transformer and a first resistor, a first end of the first inductor is used as a positive input end of the circuit, a second end of the first inductor is connected with a first end of the first capacitor and a source-side homonymy end of the first transformer, a second end of the first capacitor is grounded and used as a negative output end of the circuit, a source-side homonymy end of the first transformer is connected with a drain electrode of the first MOS transistor, a source electrode of the first MOS transistor is grounded, a grid electrode of the first MOS transistor is connected with the driving module, a secondary-side homonymy end of the first transformer is connected with a drain electrode of the second MOS transistor, and a source electrode of the second MOS transistor is connected with a first end of the first resistor, the grid electrode of the second MOS tube is connected with the PWM control module, the secondary different-name end of the first transformer is connected with the first end of the second inductor and the first end of the second capacitor, the second end of the second inductor is connected with the first end of the third capacitor and serves as the positive output end of the circuit, and the second end of the first resistor is connected with the second end of the second capacitor and the second end of the third capacitor and serves as the negative output end of the circuit.

Further, the magnetic isolation wide-range input voltage stabilizing circuit is characterized in that the second flyback synchronous rectification module comprises a third inductor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a third MOS transistor, a fourth MOS transistor, a second transformer and a second resistor, wherein a first end of the third inductor is connected with a positive input end of the circuit, a second end of the third inductor is connected with a first end of the fourth capacitor and a source-side dotted end of the second transformer, a second end of the fourth capacitor is grounded and connected with a negative output end of the circuit, a source-side dotted end of the second transformer is connected with a drain electrode of the third MOS transistor, a source electrode of the third MOS transistor is grounded, a grid electrode of the third MOS transistor is connected with the driving module, a secondary-side dotted end of the second transformer is connected with a drain electrode of the fourth MOS transistor, and a source electrode of the fourth MOS transistor is connected with a first end of the second resistor, the grid electrode of the fourth MOS tube is connected with the PWM control module, the second transformer secondary synonym end is connected with the first end of the fourth inductor and the first end of the fifth capacitor, the second end of the fourth inductor is connected with the first end of the sixth capacitor and the positive output end of the circuit, and the second end of the second resistor is connected with the second end of the fifth capacitor, the second end of the sixth capacitor and the negative output end of the circuit.

Further, the magnetic isolation wide-range input voltage stabilizing circuit is characterized in that the voltage and current feedback module is respectively connected with a positive output end of the circuit, the PWM control module, the first end of the first resistor and the first end of the second resistor, and is provided with a current equalizing function port SHARE, an output voltage adjusting port TRIM, a positive voltage compensation port + S and a negative voltage compensation port-S.

The utility model has the advantages that:

the utility model discloses a topological structure is kept apart to crisscross parallelly connected flyback synchronous rectification magnetism, and power average distribution, the device is miniaturized, reduces input/output filter device, is applicable to the high power density condition, and PWM control module is located the vice limit of power, realizes the magnetism and keeps apart, has improved the reliability.

Drawings

FIG. 1 is a schematic diagram of a magnetic isolation wide-range input voltage stabilizing circuit;

Detailed Description

For a more clear and complete description of the technical solution of the present invention, the following description is made with reference to the accompanying drawings.

Please refer to fig. 1, the present invention provides an embodiment of a magnetic isolation wide-range input voltage stabilizing circuit, which includes a first flyback synchronous rectification module 101, a second flyback synchronous rectification module 102, a voltage-current feedback module 103, a PWM control module 104, an isolation driving transformer 105 and a driving module 106, an input under-voltage protection module 107, a primary auxiliary power module 108 and a secondary auxiliary power module 109. The first flyback synchronous rectification module 101 and the second flyback synchronous rectification module 102 have the same structure, and the input end and the output end of the first flyback synchronous rectification module and the second flyback synchronous rectification module are connected in parallel, and the voltage and current feedback module 103 is respectively connected with the output end of the first flyback synchronous rectification module 101, the output end of the second flyback synchronous rectification module 102 and the PWM control module, and is used for collecting voltage and current signals to feed back the voltage and current signals to the PWM control module 104. The PWM control module 104 is connected to the switching devices on the secondary side of the first flyback synchronous rectification module 101 and the secondary side of the second flyback synchronous rectification module 102, and is connected to the switching devices on the source side of the first flyback synchronous rectification module 101 and the secondary side of the second flyback synchronous rectification module 102 through the isolation driving transformer 105 and the driving module 106, and the PWM control module 104 is configured to output a control signal to control the switching devices to be turned on and off. The undervoltage protection module 107 is respectively connected to the driving module 106 and the primary auxiliary power module 108, and is configured to control power on and off to provide undervoltage protection. The primary auxiliary power module 108 is connected to the isolation driving transformer 105, and is used for supplying power to the isolation driving transformer 105 and the input undervoltage protection module 107. The secondary auxiliary power module 109 is respectively connected to the PWM control module 104, the voltage-current feedback module 103 and the isolation driving transformer 105, and is configured to provide an operating power.

Further, referring to fig. 1, a magnetic isolation wide-range input voltage stabilizing circuit is characterized in that a first flyback synchronous rectification module 101 includes a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2, a third capacitor C3, a first MOS transistor Q1, a second MOS transistor Q2, a first transformer T1 and a first resistor R1, a first end of the first inductor L1 is used as a positive input terminal VIN + of a circuit, a second end of the first inductor L1 is connected to a first end of the first capacitor C1 and a source-side end of the first transformer T1, a second end of the first capacitor C1 is grounded and used as a negative output terminal of the circuit, the first inductor L1 is connected to the first capacitor C1 for filtering, so that an input voltage is smoother, a source-side end of the first transformer T1 is connected to a drain of the first MOS transistor Q1, a source of the first MOS transistor Q1 is grounded, a gate of the first MOS transistor Q1 is connected to receive a driving signal, and a gate drive signal is switched on, the source side of the first transformer T1 is further controlled to be excited, the dotted terminal of the secondary side of the first transformer T1 is connected with the drain of a second MOS tube Q2, the source of the second MOS tube Q2 is connected with the first end of a first resistor R1, the grid of the second MOS tube Q2 is connected with a PWM control module, PWM control signals control the on and off of a second MOS tube Q2, the secondary side of the first transformer T1 is further controlled to be excited, the dotted terminal is connected with the first end of a second inductor L2 and the first end of a second capacitor C2, the second end of the second inductor L2 is connected with the first end of a third capacitor C3 and serves as a positive output end VOUT + of the circuit, the second end of the first resistor R1 is connected with the second end of a second capacitor C2 and the second end of the third capacitor C3 and serves as a negative output end VOUT of the circuit, and the second inductor L2 is respectively connected with the second capacitor C2 and the third capacitor C3 for outputting filtering, so that the output voltage is smoother.

Further, referring to fig. 1, the second flyback synchronous rectification module 102 includes a third inductor L3, a fourth inductor L4, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a third MOS transistor Q3, a fourth MOS transistor Q4, a second transformer T2 and a second resistor R2, a first end of the third inductor L3 is connected to the positive input terminal VIN + of the circuit, a second end of the third inductor L3 is connected to the first end of the fourth capacitor C4 and the same name terminal of the source side of the second transformer T2, a second end of the fourth capacitor C4 is grounded and connected to the negative output terminal VIN + of the circuit, and the third inductor L3 is connected to the fourth capacitor C4 for filtering, so that the input voltage is smoother, a source side and a same name terminal of the second transformer T2 is connected to the drain of the third MOS transistor Q3, a source of the third MOS transistor Q3 is grounded, a gate of the third transistor Q3 is connected to the driving module for receiving the driving signal, and controlling the third transistor Q3 to turn on the source side and the third transistor T2 to turn on the second excitation side, the grid of the third MOS transistor Q3 is connected to the driving module, the dotted terminal of the secondary side of the second transformer T2 is connected to the drain of the fourth MOS transistor Q4, the source of the fourth MOS transistor Q4 is connected to the first terminal of the second resistor R2, the grid of the fourth MOS transistor Q4 is connected to the PWM control module, the PWM control signal controls the on and off of the fourth MOS transistor Q4, further controls the secondary side of the second transformer T2 to perform excitation, the dotted terminal of the secondary side of the second transformer T2 is connected to the first terminal of the fourth inductor L4 and the first terminal of the fifth capacitor C5, the second terminal of the fourth inductor L4 is connected to the first terminal of the sixth capacitor C6 and the positive output terminal of the circuit, the second terminal of the second resistor R2 is connected to the second terminal of the fifth capacitor C5, the second terminal of the sixth capacitor C6 and the negative output terminal VOUT, and the fourth inductor L4 is connected to the fifth capacitor C5 and the sixth capacitor C6 respectively for outputting filtering, so that the output voltage is smoother.

Further, referring to fig. 1, the voltage-current feedback module 103 is respectively connected to the positive output terminal VOUT +, the PWM control module, the first end of the first resistor R1, and the first end of the second resistor R2 of the circuit, and configured to obtain an electrical signal of the output terminal and feed the electrical signal back to the PWM control module, the current-sharing function port SHARE may be used for connecting multiple power supplies in parallel, the output voltage regulation port TRIM may regulate the output voltage, the positive voltage compensation port + S may compensate the voltage drop of the positive output terminal VOUT +, and the negative voltage compensation port-S may compensate the voltage drop of the negative output terminal VOUT-.

Further, referring to fig. 1, the PWM control module 104 includes a power control chip, such as LM5034, connected to the voltage-current feedback module, the gate of the second MOS transistor Q2, the gate of the fourth MOS transistor, the isolation driving transformer and the secondary auxiliary power supply, respectively, and configured to receive the feedback signal of the voltage-current feedback module, output two PWM control signals with a phase difference of 180 degrees, control the second MOS transistor and the fourth MOS transistor to be turned on and off, and transmit a new PWM control signal to the isolation driving transformer.

Further, referring to fig. 1, the isolation driving transformer 105 is respectively connected to the PWM control module, the driving module, the primary auxiliary power supply, and the secondary auxiliary power supply, and is configured to transmit the PWM control signal to the driving module on the source side.

Further, referring to fig. 1, the driving module 106 is connected to the gates of the first MOS transistor Q1 and the third MOS transistor Q3 and the isolation driving transformer, and is configured to receive a driving signal and directly control the on/off of the first MOS transistor Q1 and the third MOS transistor Q3.

Further, referring to fig. 1, the input under-voltage protection module 107 is respectively connected to the driving module and the primary auxiliary power module, and the enable control port INH is used for turning on the power supply, and when the input voltage is lower than the minimum value, the power supply is turned off, and the power supply stops working.

Further, referring to fig. 1, the primary auxiliary power module 108 is respectively connected to the input undervoltage module and the isolation driving module, and provides a working power supply for the input undervoltage protection module and the isolation driving transformer; the secondary auxiliary power supply module 109 is respectively connected to the voltage current feedback module, the PWM control module and the isolation driving transformer, and provides a working power supply for the isolation driving transformer, the PWM control module and the voltage current feedback module.

The utility model discloses a theory of operation does:

in the first stage, when the gate-source voltage Vgs of the first MOS transistor Q1 is at a high level, the first MOS transistor Q1 is turned on, at this time, the gate-source voltage Vgs of the first MOS transistor is rapidly reduced, while the voltage Vin applied to the source side excitation inductor of the first transformer T1 is unchanged, the first transformer T1 stores energy until the gate-source voltage Vgs of the first MOS transistor Q1 is at a low level, the first MOS transistor Q1 is turned off, and at this time, the second MOS transistor Q2 is turned off.

In the second stage, the gate-source voltage Vgs of the first MOS transistor Q1 changes to low level, the first MOS transistor Q1 is turned off, the excitation current charges the parasitic capacitance (Coss) between the drain and the source of the first MOS transistor Q1, so that the drain and source device voltages slowly increase, the source side excitation inductor voltage Vin slowly decreases to zero, at this time, the drain-source voltage of the first MOS transistor Q1 is Vin, the drain-source voltage of the second MOS transistor Q2 on the secondary side is the output voltage Vo, since the source side excitation current still exists, the capacitor between the drain and the source of the first MOS transistor Q1 is continuously charged, the drain-source voltage of the Q1 continues to increase, the drain-source voltage of the second MOS transistor Q2 on the secondary side continues to decrease until the parasitic diode built therein is turned on, the drain-source voltage thereof is-Vsd, the energy stored in the first transformer T1 is transferred to the secondary side load through the diode, at this time, the secondary side transformer winding is clamped at the same voltage of Vo + d, and the drain-source side voltage of the first MOS transistor Q3578 is clamped at this time, the same time, the drain-source side voltage (N + N of the source voltage of the first MOS transistor is clamped The turn ratio of the device T1, Vo is the output voltage, Vsd is the voltage drop of the rectifier Q2, and Vin is the input voltage).

And in the third stage, the second MOS tube is switched on, the energy stored by the first transformer T1 supplies power to the output through the second MOS tube, the secondary winding of the first transformer T1 bears the voltage of Vo, the current flowing through the second MOS tube slowly drops until the gate-source voltage Vgs of the second MOS tube Q2 becomes low level, and the second MOS tube Q2 is switched off.

And in the fourth stage, after the second MOS transistor Q2 is turned off, the current of the secondary winding of the first transformer T1 continuously exists, and a built-in diode of the first transformer is turned on and continues current until the first MOS transistor Q1 is turned on.

And in the fifth stage, the first MOS tube Q1 is switched on, the drain-source voltage V of the first MOS tube Q1 is rapidly reduced from the voltage of Vin + N Vo to conduction voltage drop, the drain-source voltage of the second MOS tube Q2 is changed from-Vsd to positive Vo + Vin/N, a parasitic diode is arranged in the second MOS tube Q2 for reverse recovery, a current peak is generated on the first MOS tube Q1 at the source side, and a Schottky diode is connected to the second MOS tube Q2 in parallel, so that reverse recovery loss and conduction loss can be reduced, and the working efficiency is improved.

The five stages are the working process of the single-flyback synchronous rectification circuit, the PWM control module outputs two driving signals with the phase difference of 180 degrees, the two single-flyback synchronous rectification circuits with the same structure work in parallel at 180 degrees in a staggered mode, parallel staggered flyback is achieved, and stable direct-current voltage with the frequency being the switching frequency is output.

Of course, the present invention can also have other various embodiments, and based on the embodiments, those skilled in the art can obtain other embodiments without any creative work, and all of them belong to the protection scope of the present invention.

Claims

1. The magnetic isolation wide-range input voltage stabilizing circuit is characterized by comprising a first flyback synchronous rectification module (101), a second flyback synchronous rectification module (102), a voltage and current feedback module (103), a PWM control module (104), an isolation driving transformer (105), a driving module (106), an input under-voltage protection module (107), a primary auxiliary power module (108) and a secondary auxiliary power module (109), wherein the first flyback synchronous rectification module (101) and the second flyback synchronous rectification module (102) are identical in structure, the input ends and the output ends of the first flyback synchronous rectification module and the second flyback synchronous rectification module are connected in parallel, the voltage and current feedback module (103) is respectively connected with the output end of the first flyback synchronous rectification module (101), the output end of the second flyback synchronous rectification module (102) and the PWM control module, and the PWM control module (104) is respectively connected with the first flyback synchronous rectification module (101) and the second flyback synchronous rectification module (102), (104) 102) The switching device on the secondary side is connected with the switching device on the source side of the first flyback synchronous rectification module (101) and the second flyback synchronous rectification module (102) respectively through the isolation driving transformer (105), the input under-voltage protection module (107) is connected with the driving module (106) and the primary auxiliary power supply module (108) respectively, the primary auxiliary power supply module is connected with the isolation driving transformer (105), and the secondary auxiliary power supply module (109) is connected with the PWM control module (104), the voltage and current feedback module (103) and the isolation driving transformer (105) respectively.

2. The magnetically isolated wide-range input voltage stabilizing circuit of claim 1, wherein said first flyback synchronous rectification module (101) comprises a first inductor (L1), a second inductor (L2), a first capacitor (C1), a second capacitor (C2), a third capacitor (C3), a first MOS transistor (Q1), a second MOS transistor (Q2), a first transformer (T1) and a first resistor (R1), a first end of said first inductor (L1) is used as a positive input terminal (VIN +) of the circuit, a second end of said first inductor (L1) is connected to a first end of said first capacitor (C1) and a source side of said first transformer (T1) are connected in a same name, a second end of said first capacitor (C1) is connected to ground and is used as a negative output terminal (VIN-) of the circuit, a source side of said first transformer (T1) is connected to said first drain MOS transistor (Q1), and a source side of said first MOS transistor (Q1) is connected to ground, the gate of the first MOS transistor (Q1) is connected to the driving module, the dotted terminal of the first transformer (T1) is connected to the drain of the second MOS transistor (Q2), the source of the second MOS transistor (Q2) is connected to the first terminal of the first resistor (R1), the gate of the second MOS transistor (Q2) is connected to the PWM control module, the dotted terminal of the first transformer (T1) is connected to the first terminal of the second inductor (L2) and the first terminal of the second capacitor (C2), the second terminal of the second inductor (L2) is connected to the first terminal of the third capacitor (C3) as the positive output terminal (VOUT +) of the circuit, and the second terminal of the first resistor (R1) is connected to the second terminal of the second capacitor (C2) and the second terminal of the third capacitor (C3) as the negative output terminal (VOUT-) of the circuit.

3. The magnetically isolated wide-range input voltage stabilizing circuit of claim 2, wherein said second flyback synchronous rectification module (102) comprises a third inductor (L3), a fourth inductor (L4), a fourth capacitor (C4), a fifth capacitor (C5), a sixth capacitor (C6), a third MOS transistor (Q3), a fourth MOS transistor (Q4), a second transformer (T2) and a second resistor (R2), a first end of said third inductor (L3) is connected to a positive input terminal (VIN +) of the circuit, a second end of said third inductor (L3) is connected to a first end of said fourth capacitor (C4) and a source side of said second transformer (T2) are connected to a common name terminal, a second end of said fourth capacitor (C4) is connected to ground and a negative output terminal (VIN-) of the circuit, a source side of said second transformer (T2) is connected to a common name terminal of said third drain MOS transistor (Q3), and a source side of said third MOS transistor (Q3) is connected to ground, the gate of the third MOS transistor (Q3) is connected to the driving module, the dotted terminal of the second transformer (T2) is connected to the drain of the fourth MOS transistor (Q4), the source of the fourth MOS transistor (Q4) is connected to the first terminal of the second resistor (R2), the gate of the fourth MOS transistor (Q4) is connected to the PWM control module, the dotted terminal of the second transformer (T2) is connected to the first terminal of the fourth inductor (L4) and the first terminal of the fifth capacitor (C5), the second terminal of the fourth inductor (L4) is connected to the first terminal of the sixth capacitor (C6) and the positive output terminal (VOUT +) of the circuit, and the second terminal of the second resistor (R2) is connected to the second terminal of the fifth capacitor (C5), the second terminal of the sixth capacitor (C6) and the negative output terminal (VOUT-) of the circuit.

4. The magnetically isolated wide-range input voltage regulator circuit according to claim 3, wherein the voltage-current feedback module (103) is connected to the positive output terminal (VOUT +) of the circuit, the PWM control module (104), the first terminal of the first resistor (R1), and the first terminal of the second resistor (R2), respectively, and the voltage-current feedback module (103) is provided with a current-sharing port (SHARE), an output voltage regulation port (TRIM), a positive voltage compensation port (+ S), and a negative voltage compensation port (-S).