WO2020151111A1

WO2020151111A1 - Led driver circuit based on power transistor safety protection

Info

Publication number: WO2020151111A1
Application number: PCT/CN2019/083590
Authority: WO
Inventors: 陶冬毅; 刘明龙
Original assignee: 苏州菲达旭微电子有限公司
Priority date: 2019-01-21
Filing date: 2019-04-22
Publication date: 2020-07-30
Also published as: CN109618466B; CN109618466A

Abstract

An LED driver circuit based on power transistor safety protection, comprising a ripple rejection module (1), a voltage/current conversion module (2), and a control module (3). The input end of the ripple rejection module (1) and one end of the control module (3) are both connected to a bus of a power distribution device. The ripple rejection module (1) is connected in parallel to a load (4). The voltage/current conversion module (2) comprises an amplifier (21), a power transistor (22), and a sampling resistor (23). The output end of the amplifier (21) is connected to the gate of the power transistor (22), the output end of the ripple rejection module (1) is connected to the drain of the power transistor (22), and the source of the power transistor (22) is grounded by means of the sampling resistor (23). The drain and source of the power transistor (22) and the non-inverting end of the amplifier (21) and/or the inverting input of the amplifier (21) are respectively connected to the control module (3). The control module (3) makes the current flowing through the power transistor (22) to decrease with the increase of the voltage of the bus. The LED driver circuit is designed with the control module (3), such that when the voltage of the drain of the power transistor (22) in the voltage/current conversion module (2) increases, the current flowing through the drain decreases to ensure a safe working area of the power transistor (22).

Description

An LED drive circuit based on power tube safety protection

Technical field

The invention relates to the field of LED driving, in particular to an LED driving circuit based on power tube safety protection.

Background technique

As an efficient new light source, LED is widely used in various fields of lighting due to its long life, low energy consumption, energy saving and environmental protection. In the LED drive circuit, a voltage-current conversion module composed of amplifiers and power tubes is an important core.

In the prior art, the LED driving circuit is shown in Figure 1. When the rectified bus voltage or the drain voltage of the power tube is too high, the drain current of the power tube rises, resulting in exceeding the safe working range of the power tube, resulting in reliable Sexual issues.

In the prior art, there is a lack of control over the drain current of the power tube when the bus voltage or the drain voltage of the power tube is too high, and the phenomenon that the power tube burns out frequently occurs.

Summary of the invention

In order to overcome the shortcomings of the prior art, the present invention provides an LED drive circuit based on power tube safety protection. A control module is designed in the LED drive circuit so that when the drain voltage of the power tube in the voltage-current conversion module increases, the current The current through the drain is reduced to ensure the safe working area of the power tube. The technical solution is as follows:

The present invention provides an LED drive circuit based on power tube safety protection, including a ripple suppression module, a voltage-current conversion module, and a control module. The input end of the ripple suppression module and one end of the control module are both connected to the power distribution device. Bus bar, the ripple suppression module is connected to the load in parallel;

The voltage-current conversion module includes an amplifier, a power tube, and a sampling resistor. The output terminal of the amplifier is connected to the gate of the power tube, and the output terminal of the ripple suppression module is connected to the drain of the power tube. The source of the power tube is grounded through the sampling resistor, the drain, the source, the non-inverting input terminal of the amplifier and/or the inverting input terminal of the amplifier are respectively connected to the control module, and the control module The module reduces the current flowing through the power tube as the bus voltage increases.

Regarding the specific implementation scheme of the control module, there are at least the following five ways:

Manner 1: The control module includes a first resistor, a second resistor, and a third resistor, and the first resistor is arranged between the bus bar of the power distribution device and the inverting input terminal of the amplifier;

The second resistor and the third resistor form a first branch through a series connection, the first branch is connected to the power tube in parallel, and one end of the third resistor is connected to the sampling resistor;

The intermediate connection end of the second resistor and the third resistor is connected to the inverting input end of the amplifier, and the non-inverting input end of the amplifier is connected to a first reference voltage source.

Manner 2: The control module includes a first transconductance amplifier, a first constant current source, a grounding capacitor, a fourth resistor, and a fifth resistor, the output terminal of the first constant current source, and the output terminal of the first transconductance amplifier , The positive pole of the grounding capacitor is connected to the non-inverting input terminal of the amplifier;

The fourth resistor and the fifth resistor form a second branch through a series connection, and the second branch is connected to the power tube in parallel. The input terminal of the first transconductance amplifier and the fifth resistor Both are connected to the middle connecting end of the power tube and the sampling resistor, and the middle connecting end of the fourth resistor and the fifth resistor is connected to the inverting input end of the amplifier.

Manner 3: The control module includes a sixth resistor and a seventh resistor, the sixth resistor and the seventh resistor are connected in series to form a third branch, and the third branch is connected to the power tube in parallel. The intermediate connection end of the sixth resistor and the seventh resistor is connected to the inverting input end of the amplifier, and the non-inverting input end of the amplifier is connected to a second reference voltage source.

Mode 4: The control module includes a second transconductance amplifier, a second constant current source, a ground resistance, an eighth resistor, and a ninth resistor, the output terminal of the second constant current source, and the output terminal of the second transconductance amplifier , One end of the grounding resistor is connected to the non-inverting input end of the amplifier, and the other end of the grounding resistor is grounded;

The intermediate connection end of the power tube and the sampling resistor is connected to the inverting input end of the amplifier;

One end of the eighth resistor is connected to the bus bar of the power distribution device, the other end is connected to one end of the ninth resistor, the other end of the ninth resistor is grounded, and the middle connecting end of the eighth resistor and the ninth resistor is connected to the The non-inverting input terminal of the second transconductance amplifier is connected, and the inverting input terminal of the second transconductance amplifier is connected to a third reference voltage source.

Manner 5. The control module includes a tenth resistor, the tenth resistor is connected to the power tube in parallel, the non-inverting input end of the amplifier is connected to a fourth reference voltage source, and the power tube and the sampling resistor are in the middle The connecting terminal is connected with the inverting input terminal of the amplifier.

Regarding the specific implementation of the ripple suppression module, there are at least the following two ways:

Manner 1: The ripple suppression module includes a first capacitor, the positive electrode of the first capacitor is connected to the bus bar of the power distribution device, the negative electrode of the first capacitor is connected to the input end of the power tube, and the load is connected in parallel The way is connected with the first capacitor.

Manner 2: The ripple suppression module includes a second capacitor, a third capacitor, a voltage divider resistor, a third constant current source, and a second power tube. The anode of the second capacitor is connected to the bus bar of the power distribution device. The load, the voltage divider resistor, and the third constant current source form a fourth branch in series connection, the fourth branch is connected to the second capacitor in parallel, and the third capacitor is connected in parallel to the first capacitor. Three constant current sources are connected, the voltage dividing resistor and the third constant current source form a fifth branch through series connection, and the drain and source of the second power tube are connected in parallel with the fifth branch , The intermediate connection end of the voltage dividing resistor and the third constant current source is connected to the gate of the second power tube.

The beneficial effects brought by the technical solution provided by the present invention are as follows:

1) When the rectified bus voltage or power tube drain voltage is too high, the control module controls the power tube current to gradually decrease with the increase of input voltage or drain voltage to ensure that the power tube works in a safe working area and is stable High sex

2) The bus voltage and drain voltage can individually control the power tube current to work in the safe working area, or together control the power tube current to work in the safe working area;

3) The ripple suppression module filters the modulated power tube current to reduce the ripple coefficient of the load module.

Description of the drawings

In order to explain the technical solutions in the embodiments of the present invention more clearly, the following will briefly introduce the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained from these drawings without creative work.

FIG. 1 is a schematic diagram of the structure of an LED driving circuit in the prior art;

2 is a schematic diagram of the topological structure of an LED drive circuit based on power tube safety protection provided by an embodiment of the present invention;

3 is a schematic diagram of a first implementation circuit of an LED drive circuit based on power tube safety protection provided by an embodiment of the present invention;

4 is a schematic diagram of a second implementation circuit of an LED drive circuit based on power tube safety protection provided by an embodiment of the present invention;

5 is a schematic diagram of a third implementation circuit of an LED drive circuit based on power tube safety protection provided by an embodiment of the present invention;

6 is a schematic diagram of a fourth implementation circuit of an LED drive circuit based on power tube safety protection provided by an embodiment of the present invention;

7 is a schematic diagram of a fifth implementation circuit of an LED drive circuit based on power tube safety protection provided by an embodiment of the present invention;

FIG. 8 is a working waveform diagram of an LED driving circuit based on power tube safety protection provided by an embodiment of the present invention.

Wherein, the reference signs include: 1-ripple suppression module, 111-first capacitor, 121-second capacitor, 122-third capacitor, 123-voltage divider resistor, 124-third constant current source, 125-second Power tube, 2-voltage-current conversion module, 21-amplifier, 22-power tube, 23-sampling resistor, 3-control module, 311-first resistor, 312-second resistor, 313-third resistor, 321-th A transconductance amplifier, 322-first constant current source, 323-grounded capacitor, 324-fourth resistor, 325-fifth resistor, 331-sixth resistor, 332-seventh resistor, 341-second transconductance amplifier, 342-second constant current source, 343-grounding resistance, 344-eighth resistance, 345-ninth resistance, 351-tenth resistance, 4-load.

detailed description

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only It is a part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be noted that the terms "first" and "second" in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and not necessarily used to describe a specific sequence or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in a sequence other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations of them are intended to cover non-exclusive inclusion.

The present invention provides an LED drive circuit based on power tube safety protection. As shown in FIG. 2, the drive circuit includes a ripple suppression module 1, a voltage-current conversion module 2, and a control module 3. The ripple suppression module 1 The input terminal of and one end of the control module 3 are both connected to the bus of the power distribution device, and the ripple suppression module 1 is connected to the load 4 in parallel;

The voltage-current conversion module 2 includes an amplifier 21, a power tube 22, and a sampling resistor 23. The output terminal of the amplifier 21 is connected to the gate of the power tube 22. The output terminal of the ripple suppression module 1 is connected to the The drain of the power tube 22 is connected, the source of the power tube 22 is grounded through the sampling resistor 23, the drain and source of the power tube 22, the non-inverting input terminal of the amplifier 21 and/or the inverting of the amplifier 21 The input terminals are respectively connected to the control module 3, and the control module 3 reduces the current flowing through the power tube 22 as the bus voltage increases.

Regarding the specific implementation scheme of the control module 3, the present invention provides the following embodiments:

Example 1

In one embodiment of the present invention, an LED drive circuit based on power tube safety protection is provided. As shown in FIG. 3, the ripple suppression module 1 of the drive circuit includes a first capacitor 111, and the The positive pole is connected to the bus bar of the power distribution device, the negative pole of the first capacitor 111 is connected to the input end of the power tube 22, the load 4 is connected to the first capacitor 111 in parallel, and the first capacitor 111 is used for To suppress the current ripple of the load module.

The control module 3 of the driving circuit includes a first resistor 311 (hereinafter may be referred to as R11), a second resistor 312 (hereinafter may be referred to as R12), and a third resistor 313 (hereinafter may be referred to as R10). The first resistor 311 is set at Between the bus bar of the power distribution device and the inverting input terminal of the amplifier 21; the second resistor 312 and the third resistor 313 form a first branch through a series connection, and the first branch is connected in parallel It is connected to the power tube 22 in a way, one end of the third resistor 313 is connected to the sampling resistor 23 (referred to as R1s in Embodiment 1); the middle connecting end of the second resistor 312 and the third resistor 313 is connected to the The inverting input terminal of the amplifier 21 is connected, and the non-inverting input terminal of the amplifier 21 is connected to a first reference voltage source (the first reference voltage is V _ref1 ).

The following verifies that the instantaneous current of the power tube in the driving circuit of embodiment 1 decreases with the increase of drain voltage or bus voltage: For the circuit in Figure 3, when R11>>R10>>R1s and R12>>R10 are satisfied At R1s, the instantaneous current of the power tube satisfies the following formula:

I _p =[V _ref1 -(V _bus /R11+V _p /R12)*R10]/R1s, where I _p is the instantaneous current of the power tube, V _bus is the bus voltage, V _p is the drain voltage of the power tube, and V _ref1 is the first reference voltage connected to the non-inverting input terminal of the amplifier;

Obviously, as V _bus and V _p gradually increase, I _p gradually decreases, and V _bus and V _{p are} jointly modulated, and I _{p is} within the safe operating area.

The above ">>" is much larger than the symbol, which means, for example, calculating a+b, if a>>b, in order to simplify the calculation, the existence of b can be ignored in the inaccurate summation calculation, and a>>b The qualification condition can generally be set as a larger than b by two orders of magnitude or more. The ">>" in the following several embodiments is the same, and will not be repeated.

Example 2

In an embodiment of the present invention, an LED drive circuit based on power tube safety protection is provided. As shown in FIG. 4, the ripple suppression module 1 of the drive circuit includes a first capacitor 111, and the The positive pole is connected to the bus bar of the power distribution device, the negative pole of the first capacitor 111 is connected to the input end of the power tube 22, the load 4 is connected to the first capacitor 111 in parallel, and the first capacitor 111 is used for Suppress the current ripple of the load module.

The control module 3 of the driving circuit includes a first transconductance amplifier 321, a first constant current source 322, a grounded capacitor 323, a fourth resistor 324 (hereinafter may be referred to as R21), and a fifth resistor 325 (hereinafter may be referred to as R20), so The output terminal of the first constant current source 322, the output terminal of the first transconductance amplifier 321, and the positive electrode of the grounding capacitor 323 are all connected to the non-inverting input terminal of the amplifier 21;

The fourth resistor 324 and the fifth resistor 325 are connected in series to form a second branch, and the second branch is connected to the power tube 22 in parallel. The input terminal of the first transconductance amplifier 321 , The fifth resistor 325 is connected to the middle connecting end of the power tube 22 and the sampling resistor 23 (referred to as R2s in Embodiment 2), and the middle connecting end of the fourth resistor 324 and the fifth resistor 325 is connected to the amplifier 21 The inverting input terminal is connected.

The following verifies that the instantaneous current of the power tube in the driving circuit of Embodiment 2 decreases with the increase of drain voltage or bus voltage: For the circuit in Figure 4, when R21>>R20>>R2s is satisfied, the average current of the power tube meets The following formula:

I _{p_average} = I _ref /(R2s*Gm2), where I _{p_average} is the average current of the power tube, I _ref is the reference current of the first constant current source, and Gm2 is the transconductance gain of the first transconductance amplifier;

The instantaneous current of the power tube satisfies the following formula:

I _p =(V _c -V _p /R21*R20)/R2s, where I _p is the instantaneous current of the power tube, V _c is the output voltage of the first constant current source, and V _p is the drain voltage of the power tube;

Obviously, with the gradual increase of V _p , the instantaneous value of I _p gradually decreases, and I _p is modulated by V _p in the safe operating area, but the average value of I _p remains unchanged.

Example 3

In one embodiment of the present invention, an LED drive circuit based on power tube safety protection is provided. As shown in FIG. 5, the ripple suppression module 1 of the drive circuit includes a second capacitor 121, a third capacitor 122, and The voltage resistor 123, the third constant current source 124 and the second power tube 125, the anode of the second capacitor 121 is connected to the bus bar of the power distribution device, and the load 4 is connected to the voltage dividing resistor 123 and the third constant current source 124 The series connection forms a fourth branch, the fourth branch is connected to the second capacitor 121 in parallel, and the third capacitor 122 is connected to the third constant current source 124 in parallel. The voltage dividing resistor 123 and the third constant current source 124 are connected in series to form a fifth branch. The drain and source of the second power tube 125 are connected to the fifth branch in parallel. The middle connecting end of the resistor 123 and the third constant current source 124 is connected to the gate of the second power tube 125, and the ripple suppression module 1 is used to suppress the current ripple of the load module.

The control module 3 of the driving circuit includes a sixth resistor 331 (hereinafter may be referred to as R31) and a seventh resistor 332 (hereinafter may be referred to as R30). The sixth resistor 331 and the seventh resistor 332 are connected in series and connected in parallel to the power At both ends of the tube 22, the intermediate connection end of the sixth resistor 331 and the seventh resistor 332 is connected to the inverting input end of the amplifier 21, and the noninverting input end of the amplifier 21 is connected to a second reference voltage source (the first The second reference voltage is V _ref2 ). In Embodiment 3, the sampling resistor 23 is R3s.

The following verifies that the instantaneous current of the power tube in the driving circuit of Example 3 decreases with the increase of drain voltage or bus voltage: For the circuit in Figure 5, when R31>>R30>>R3s is satisfied, the instantaneous current of the power tube meets The following formula:

I _p =(V _ref -V _p /R31*R30)/R3s, where I _p is the instantaneous current of the power tube, V _ref2 is the second reference voltage connected to the non-inverting input terminal of the amplifier, and V _p is the drain voltage of the power tube;

Obviously, with the gradual increase of V _p , the instantaneous value of I _p gradually decreases, and I _p is modulated by V _p in the safe operating area.

Example 4

In an embodiment of the present invention, an LED drive circuit based on power tube safety protection is provided. As shown in FIG. 6, the ripple suppression module 1 of the drive circuit includes a second capacitor 121, a third capacitor 122, and a The voltage resistor 123, the third constant current source 124 and the second power tube 125, the anode of the second capacitor 121 is connected to the bus bar of the power distribution device, and the load 4 is connected to the voltage dividing resistor 123 and the third constant current source 124 The series connection forms a fourth branch, the fourth branch is connected to the second capacitor 121 in parallel, and the third capacitor 122 is connected to the third constant current source 124 in parallel. The voltage dividing resistor 123 and the third constant current source 124 are connected in series to form a fifth branch. The drain and source of the second power tube 125 are connected to the fifth branch in parallel. The middle connecting end of the resistor 123 and the third constant current source 124 is connected to the gate of the second power tube 125, and the ripple suppression module 1 is used to suppress the current ripple of the load module.

The control module 3 of the driving circuit includes a second transconductance amplifier 341, a second constant current source 342, a grounding resistor 343, an eighth resistor 344, and a ninth resistor 345. The output terminal of the second constant current source 342, the The output ends of the two transconductance amplifiers 341 and one end of the grounding resistor 343 are both connected to the non-inverting input end of the amplifier 21, and the other end of the grounding resistor 343 is grounded;

The intermediate connection end of the power tube 22 and the sampling resistor 23 is connected to the inverting input end of the amplifier 21;

One end of the eighth resistor 344 (hereinafter referred to as R41) is connected to the bus bar of the power distribution device, the other end is connected to one end of the ninth resistor 345, and the other end of the ninth resistor 345 (hereinafter referred to as R40) is grounded, The middle connecting end of the eighth resistor 344 and the ninth resistor 345 is connected to the non-inverting input end of the second transconductance amplifier 341, and the inverting input end of the second transconductance amplifier 341 is connected to a third reference voltage source ( The third reference voltage is V _ref3 ).

The following verifies that the instantaneous current of the power tube in the driving circuit of Embodiment 4 decreases with the increase of drain voltage or bus voltage: For the circuit in Figure 6, when R41>>R40 is satisfied, the instantaneous current of the power tube satisfies the following formula:

When V _bus /R41*R40-V _ref3 >= 0,

I _p =[I _ref -(V _bus /R41*R40-V _ref3 )*Gm4]*R4c/R4s, where I _p is the instantaneous current of the power tube, V _bus is the bus voltage, and V _ref3 is the second transconductance amplifier The third reference voltage connected to the inverting input terminal of, I _ref is the reference current of the second constant current source, and Gm4 is the transconductance gain of the second transconductance amplifier;

When V _bus /R41*R40-V _ref ＜0,

I _p ＝I _ref *R4c/R4s

Obviously, as V _bus gradually increases, the instantaneous value of I _p gradually decreases, and I _p is modulated by V _bus in the safe operating area.

Example 5

In an embodiment of the present invention, an LED drive circuit based on power tube safety protection is provided. As shown in FIG. 7, the ripple suppression module 1 of the drive circuit includes a first capacitor 111. The positive pole is connected to the bus bar of the power distribution device, the negative pole of the first capacitor 111 is connected to the input end of the power tube 22, the load 4 is connected to the first capacitor 111 in parallel, and the first capacitor 111 is used for Suppress the current ripple of the load module.

The control module 3 of the driving circuit includes a tenth resistor 351 (hereinafter may be referred to as R5), the tenth resistor 351 is connected in parallel with the power tube 22, and the non-inverting input terminal of the amplifier 21 is connected to a fourth reference voltage source (which The fourth reference voltage is V _ref4 ), and the intermediate connection end of the power tube 22 and the sampling resistor 23 is connected to the inverting input end of the amplifier 21.

The following verifies that the instantaneous current of the power tube in the driving circuit of Embodiment 5 decreases with the increase of drain voltage or bus voltage: For the circuit in Figure 7, when R5>>R5s is satisfied, the instantaneous current of the power tube satisfies the following formula:

_{_{I p = V ref4 / R5s-}} V p / R5, where, I _p is the current instantaneous power tube, V _p of the power transistor drain voltage, V _ref4 for the amplifier inverting input terminal connected to a fourth reference voltage.

The working waveforms of the LED drive circuit based on power tube safety protection provided by the above embodiments 1-5 are shown in Figure 8. It can be seen that the control module in the LED drive circuit of the present invention can control the drain current I _{p of the} power tube as As the bus voltage V _bus or the drain voltage V _p rises and decreases, the power tube works in a safe area.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection of the present invention. Within range.

Claims

An LED drive circuit based on power tube safety protection, which is characterized by comprising a ripple suppression module (1), a voltage-current conversion module (2), and a control module (3). The input of the ripple suppression module (1) And one end of the control module (3) are both connected to the bus bar of the power distribution device, and the ripple suppression module (1) is connected to the load (4) in parallel;

The voltage-current conversion module (2) includes an amplifier (21), a power tube (22) and a sampling resistor (23). The output terminal of the amplifier (21) is connected to the gate of the power tube (22), so The output end of the ripple suppression module (1) is connected to the drain of the power tube (22), the source of the power tube (22) is grounded through the sampling resistor (23), and the power tube (22) ), the drain, the source, the non-inverting input end of the amplifier (21) and/or the inverting input end of the amplifier (21) are respectively connected to the control module (3), and the control module (3) causes the flow through all The current of the power tube (22) decreases as the bus voltage increases.
The driving circuit according to claim 1, wherein the control module (3) comprises a first resistor (311), a second resistor (312) and a third resistor (313), the first resistor (311) ) Is arranged between the bus bar of the power distribution device and the inverting input terminal of the amplifier (21);

The second resistor (312) and the third resistor (313) are connected in series to form a first branch, the first branch is connected to the power tube (22) in parallel, and the third resistor One end of (313) is connected to the sampling resistor (23);

The intermediate connection end of the second resistor (312) and the third resistor (313) is connected to the inverting input end of the amplifier (21), and the non-inverting input end of the amplifier (21) is connected to the first reference voltage source.
The driving circuit according to claim 1, wherein the control module (3) comprises a first transconductance amplifier (321), a first constant current source (322), a grounding capacitor (323), and a fourth resistor ( 324) and the fifth resistor (325). The output terminal of the first constant current source (322), the output terminal of the first transconductance amplifier (321), and the positive electrode of the grounding capacitor (323) are all connected to the amplifier (21). )'S non-inverting input terminal connection;

The fourth resistor (324) and the fifth resistor (325) are connected in series to form a second branch, the second branch is connected to the power tube (22) in parallel, and the first span The input end of the conductance amplifier (321) and the fifth resistor (325) are both connected to the intermediate connection end of the power tube (22) and the sampling resistor (23). The fourth resistor (324) and the fifth resistor (325) The middle connection terminal of) is connected to the inverting input terminal of the amplifier (21).
The driving circuit according to claim 1, wherein the control module (3) comprises a sixth resistor (331) and a seventh resistor (332), and the sixth resistor (331) and the seventh resistor (332) ) A third branch is formed through a series connection, the third branch is connected to the power tube (22) in parallel, and the middle connecting end of the sixth resistor (331) and the seventh resistor (332) It is connected to the inverting input terminal of the amplifier (21), and the non-inverting input terminal of the amplifier (21) is connected to a second reference voltage source.
The driving circuit according to claim 1, wherein the control module (3) comprises a second transconductance amplifier (341), a second constant current source (342), a grounding resistance (343), and an eighth resistance ( 344) and a ninth resistor (345). The output terminal of the second constant current source (342), the output terminal of the second transconductance amplifier (341), and one end of the grounding resistor (343) are all connected to the amplifier (21 ) Is connected to the in-phase input end, and the other end of the grounding resistor (343) is grounded;

The intermediate connection end of the power tube (22) and the sampling resistor (23) is connected to the inverting input end of the amplifier (21);

One end of the eighth resistor (344) is connected to the bus bar of the power distribution device, the other end is connected to one end of the ninth resistor (345), the other end of the ninth resistor (345) is grounded, and the eighth resistor ( 344) The intermediate connection end of the ninth resistor (345) is connected to the non-inverting input end of the second transconductance amplifier (341), and the inverting input end of the second transconductance amplifier (341) is connected to the third reference voltage source.
The drive circuit according to claim 1, wherein the control module (3) comprises a tenth resistor (351), and the tenth resistor (351) is connected to the power tube (22) in parallel, The non-inverting input end of the amplifier (21) is connected to a fourth reference voltage source, and the intermediate connection end of the power tube (22) and the sampling resistor (23) is connected to the inverting input end of the amplifier (21).
The driving circuit according to claim 1, wherein the ripple suppression module (1) comprises a first capacitor (111), and the anode of the first capacitor (111) is connected to the bus bar of the power distribution device, so The negative electrode of the first capacitor (111) is connected to the input end of the power tube (22), and the load (4) is connected to the first capacitor (111) in parallel.
The drive circuit according to claim 1, wherein the ripple suppression module (1) comprises a second capacitor (121), a third capacitor (122), a voltage divider (123), and a third constant current source (124) and the second power tube (125), the anode of the second capacitor (121) is connected to the bus bar of the power distribution device, the load (4) is connected with the voltage divider (123), and the third constant current source ( 124) A fourth branch is formed through a series connection, the fourth branch is connected to the second capacitor (121) in parallel, and the third capacitor (122) is connected to the third constant current in parallel. The source (124) is connected, the voltage dividing resistor (123) and the third constant current source (124) form a fifth branch through a series connection, and the drain and source of the second power tube (125) are connected in parallel It is connected to the fifth branch, and the intermediate connection end of the voltage dividing resistor (123) and the third constant current source (124) is connected to the gate of the second power tube (125).