CN115085550A - Step-down DC converter - Google Patents

Step-down DC converter Download PDF

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Publication number
CN115085550A
CN115085550A CN202210880236.3A CN202210880236A CN115085550A CN 115085550 A CN115085550 A CN 115085550A CN 202210880236 A CN202210880236 A CN 202210880236A CN 115085550 A CN115085550 A CN 115085550A
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China
Prior art keywords
output
current
control signal
voltage
input end
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Chinese (zh)
Inventor
钱春
杨成
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Shanghai Panchip Microelectronics Co ltd
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Shanghai Panchip Microelectronics Co ltd
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
    • H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
    • H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
    • H02M3/158—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/0003—Details of control, feedback or regulation circuits
    • H02M1/0009—Devices or circuits for detecting current in a converter
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
    • H02M1/088—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)

Abstract

The invention relates to the technical field of integrated circuits, in particular to a buck direct current converter, which comprises: an output module; the current sensing module generates a current control signal according to the peak current and the first feedback voltage; the delay unit generates a delay control signal according to the peak current; the voltage sensing module acquires a second feedback voltage and generates a voltage control signal according to the second feedback voltage; the output module controls the self-powered circuit to get electricity according to the current control signal, the delay control signal and the voltage control signal, and outputs output current to the load circuit. The invention has the beneficial effects that: the current sensing module is provided with the delay unit to replace a zero crossing point comparator in the prior art, and the output module can be discharged by controlling the generation of the delay control signal under the relatively stable output condition, so that the problem that the peak current of the inductor is mistakenly triggered due to the shaking of the grounding end by grounding and sensing in the prior art is solved, and the relatively stable output effect is realized.

Description

Step-down DC converter
Technical Field
The invention relates to the technical field of integrated circuits, in particular to a buck direct-current converter.
Background
The step-down DC converter is characterized by that it utilizes an oscillating circuit to convert a DC voltage into a high-frequency power supply, then utilizes a pulse transformer and a rectifier-filter circuit to output the required DC voltage so as to make the output voltage reduce amplitude and ripple, and can output stable DC voltage.
In the prior art, many technical schemes of a buck type direct current converter exist. For example, chinese patent 201210027568.3 discloses a buck converter. The scheme provides a voltage reduction conversion circuit based on PFM control, which comprises a zero-crossing comparator used for detecting the zero-crossing point of inductive current, a current comparator used for detecting the peak value of the inductive current and a voltage comparator used for detecting output voltage, wherein a PFM control module controls the switch tube to be switched on and off according to the detection result, and then voltage reduction direct current output is realized.
However, in the implementation process, the inventor finds that, in the implementation process of the above technical solution, since the zero-crossing comparator is connected to the inductor front stage through the forward input end, and the reverse input end is grounded, the zero-crossing time of the inductor current is determined. However, due to the ground design of the integrated circuit, the ground terminal may be jittered, which may cause the comparator to be triggered erroneously, thereby affecting the conversion efficiency of the entire conversion circuit.
Disclosure of Invention
In view of the above problems in the prior art, a buck dc converter is provided.
The specific technical scheme is as follows:
a buck dc converter comprising:
the input end of the output module is connected with the power supply circuit, and the output end of the output module is connected with the load circuit;
the input end of the current sensing module is connected with the current feedback end and the first voltage feedback end of the output module, the output end of the current sensing module is connected with the control end of the output module, the current sensing module obtains peak current and first feedback voltage from the output module, and generates a current control signal according to the peak current and the first feedback voltage;
the current sensing module is also provided with a delay unit, and the delay unit generates a delay control signal according to the peak current;
the input end of the voltage sensing module is connected with the second voltage feedback end of the output module, the output end of the voltage sensing module is connected with the control end of the output module, and the voltage sensing module acquires second feedback voltage from the output module and generates a voltage control signal according to the second feedback voltage;
the output module obtains electricity from the power supply circuit according to the control of the current control signal, the delay control signal and the voltage control signal, and outputs output current to the load circuit.
Preferably, the output module includes:
a power input end of the control unit is an input end of the output module, a signal input end of the control unit is a control end of the output module, and the control unit receives the current control signal, the voltage control signal and the delay control signal respectively;
the first end of the inductor is connected with the output end of the control unit, and the second end of the inductor is the output end of the output module;
the first end of the output capacitor is connected with the second end of the inductor, and the second end of the output capacitor is grounded;
the first end of the inductor is a first voltage feedback end of the output module, and the second end of the inductor is a second voltage feedback end of the output module.
Preferably, the control unit includes:
a logic controller that receives the current control signal, the voltage control signal, and the delay control signal, respectively;
the input end of the first switch tube is connected with the power supply circuit, and the output end of the first switch tube is the output end of the output module;
the input end of the second switch tube is connected with the output end of the first switch tube, and the output end of the second switch tube is grounded;
a first control end of the logic controller is connected with the grid electrode of the first switching tube, and a second control end of the control unit is connected with the grid electrode of the second switching tube;
the logic controller respectively controls the first switch tube and the second switch tube according to the current control signal, the voltage control signal and the time delay control signal.
Preferably, the current sensing module includes:
the current sensor acquires peak current on the inductor and generates peak voltage output according to the peak current;
the same-direction input end of the first comparator is connected with the input end of the current sensing module, the reverse-direction input end of the first comparator is connected with the first output end of the current sensor, and the output end of the first comparator is connected with the output module to send the current control signal;
the first input end of the delay unit is connected with the output end of the first comparator, the second input end of the delay unit is connected with the second output end of the current sensor, and the output end of the delay unit is connected with the output module to send the delay control signal.
Preferably, the delay unit includes:
the output end of the constant current source is connected with the first end of the delay capacitor, and the second end of the delay capacitor is grounded;
the same-direction input end of the second comparator is connected with the first end of the delay capacitor, and the reverse-direction input end of the second comparator is connected with the output end of the current sensor;
a clock input end of the D-type trigger is connected with an output end of the first comparator, a data input end of the D-type trigger is at a high level, and an output end of the D-type trigger is connected with the output module to send the delay control signal;
the input end of the feedback switch tube is connected with the homodromous input end of the second comparator, the output end of the feedback switch tube is grounded, and the grid electrode of the feedback switch tube is connected with the output end of the D-type trigger.
Preferably, the second output terminal of the current sensor is grounded through a pull-down resistor.
Preferably, the voltage sensing module includes:
a reference voltage source;
and the same-direction input end of the third comparator is connected with the output end of the reference voltage source, and the reverse-direction input end of the third comparator is connected with the input end of the voltage sensing module.
Preferably, the logic controller operates in PFM mode.
The technical scheme has the following advantages or beneficial effects: the current sensing module is provided with the delay unit to replace a zero crossing point comparator in the prior art, and the output module can be discharged by controlling the generation of the delay control signal under the relatively stable output condition, so that the problem that the peak current of the inductor is mistakenly triggered due to the shaking of the grounding end by grounding and sensing in the prior art is solved, and the relatively stable output effect is realized.
Drawings
Embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings. The drawings are, however, to be regarded as illustrative and explanatory only and are not restrictive of the scope of the invention.
FIG. 1 is a schematic diagram of an embodiment of the present invention;
FIG. 2 is a schematic diagram of a delay unit according to an embodiment of the present invention;
FIG. 3 is a timing diagram illustrating operation of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
The invention is further described with reference to the following drawings and specific examples, which are not intended to be limiting.
The invention comprises the following steps:
a buck dc converter, as shown in fig. 1, comprising:
the input end of the output module 1 is connected with the power supply circuit VIN, and the output end of the output module 1 is connected with the load circuit OUT;
the current sensing module 2 is connected with the current feedback end and the first voltage feedback end of the output module at the input end of the current sensing module 2, the output end of the current sensing module 2 is connected with the control end of the output module 1, the current sensing module 2 obtains peak current and first feedback voltage from the output module 1, and a current control signal is generated according to the peak current and the first feedback voltage;
the current sensing module 2 is further provided with a delay unit 21, and the delay unit 21 generates a delay control signal according to the peak current;
the input end of the voltage sensing module 3 is connected with the second voltage feedback end of the output module 1, the output end of the voltage sensing module 3 is connected with the control end of the output module 1, and the voltage sensing module 3 acquires a second feedback voltage from the output module 1 and generates a voltage control signal according to the second feedback voltage;
the output module 1 controls the self-powered circuit to get power according to the current control signal, the delay control signal and the voltage control signal, and outputs an output current to the load circuit OUT.
Specifically, for the dc converter in the prior art, the zero crossing time of the inductor L1 needs to be detected according to the ground terminal, which causes the problem that the comparator may generate the false triggering due to the ground terminal shaking, in this embodiment, the output module 1 is adjusted, so that the output module 1 can output according to the current control signal, the delay control signal and the voltage control signal, and the zero crossing signal of the inductor L1 in the prior art is replaced by the delay control signal with a relatively stable period, which improves the stability of circuit control and avoids the problem of the false triggering due to the ground terminal shaking.
In a preferred embodiment, the output module 1 comprises:
the power supply input end of the control unit 11 is the input end of the output module 1, the signal input end of the control unit 11 is the control end of the output module 1, and the control unit 11 receives a current control signal, a voltage control signal and a delay control signal respectively;
a first end of an inductor L1 and an inductor L1 are connected with an output end of the control unit 11, and a second end of an inductor L1 is an output end of the output module 1;
a first end of the output capacitor C1 is connected with a second end of the inductor L1, and a second end of the output capacitor C1 is grounded;
the first terminal of the inductor L1 is a current feedback terminal of the output module 1, and the second terminal of the inductor L1 is a voltage feedback terminal of the output module 1.
Specifically, in order to achieve a better control effect, in this embodiment, the control unit 11 is configured to control the current output according to the received current control signal, the voltage control signal and the delay control signal, so that the resonant circuit composed of the inductor L1 and the output capacitor C1 periodically oscillates, and a specific dc signal is output to the load circuit OUT.
In a preferred embodiment, the control unit 11 comprises:
the logic controller U1, the logic controller U1 receives the current control signal, the voltage control signal and the delay control signal respectively;
the input end of the first switch tube Q1 is connected with the power supply circuit Vin, and the output end of the first switch tube Q1 is the output end of the output module 1;
the input end of a second switching tube Q2, the input end of a second switching tube Q2 is connected with the output end of the first switching tube Q1, and the output end of the second switching tube Q2 is grounded;
a first control end of the logic controller U1 is connected to the gate of the first switching tube Q1, and a second control end of the control unit 11 is connected to the gate of the second switching tube Q2;
the logic controller U1 controls the first switch Q1 and the second switch Q2 according to the current control signal, the voltage control signal and the delay control signal.
Specifically, in order to achieve a better control effect, in this embodiment, the logic controller U1 is arranged to drive the half-bridge output circuit composed of the first switch tube Q1 and the second switch tube Q2 to output a voltage to the backward inductor L1 based on the PFM mode according to the current control signal, the voltage control signal, and the delay control signal, so as to achieve a better step-down output effect by controlling charging and discharging of the resonant circuit.
In an implementation, the first switching tube Q1 and the second switching tube Q2 may be implemented by MOS transistors or other forms of power devices, such as IGBT devices. In this embodiment, the first switch Q1 is a PMOS transistor, and has a source connected to the power supply circuit Vin as an output terminal and a drain as an output terminal; the second switch Q2 is an NMOS transistor with its drain as the input terminal and source as the output terminal. However, in other embodiments, the first switch Q1 may be configured as an NMOS transistor or other devices, and the second switch Q2 may be configured as a PMOS transistor or other devices, and the input and the output thereof may be adaptively adjusted according to actual needs, which is not limited herein.
In a preferred embodiment, the current sensing module 2 comprises:
the current sensor Isense acquires peak current on the inductor L1 and generates peak voltage output according to the peak current;
a first comparator CMP1, wherein the same-direction input end of the first comparator CMP1 is connected with the input end of the current sensing module 2, the reverse-direction input end of the first comparator CMP1 is connected with the first output end of the current sensor Isense, and the output end of the first comparator CMP1 is connected with the output module 1 to send a current control signal;
a first input end of the delay unit 21 is connected to the output end of the first comparator CMP1, a second input end of the delay unit 21 is connected to the second output end of the current sensor Isense, and an output end of the delay unit 21 is connected to the output module 1 to send a delay control signal.
Specifically, for the buck dc converter in the prior art, which is controlled by the zero-crossing signal of the inductor L1, and may cause the comparator to be triggered erroneously due to the ground terminal jitter, thereby affecting the output efficiency of the converter, in this embodiment, the delay unit 21 is configured to generate the delay control signal according to the peak voltage output by the current sensor Isense, and the delay control signal is only related to the peak current of the inductor L1, so that the problem of the comparator being triggered erroneously due to the ground terminal jitter is avoided, and thus the stable control effect of the output module 1 is achieved.
In implementation, the non-inverting input terminal of the first comparator CMP1 is connected to the first terminal of the inductor L1, so as to receive the current output by the control unit 11 through the half bridge, i.e., the charging current of the inductor L1; the inverting input of the first comparator CMP1 is connected to the output current of the current sensor Isense, which detects the peak current in the inductor L1 via the sense coil and converts the peak current into a peak voltage via a resistor, which is input to the inverting input of the first comparator CMP 1.
In a preferred embodiment, as shown in fig. 2, the delay unit 21 comprises:
the output end of the constant current source I0, the output end of the constant current source I0 is connected with the first end of the delay capacitor C1, and the second end of the delay capacitor C1 is grounded;
a second comparator CMP2, wherein the same-direction input end of the second comparator CMP2 is connected with the first end of the delay capacitor C1, and the reverse-direction input end of the second comparator CMP2 is connected with the output end of the current sensor 2;
the clock input end of the D-type trigger DFF is connected with the output end of the first comparator CMP1, the data input end of the D-type trigger DFF is at a high level, and the output end of the D-type trigger DFF is connected with the output module 1 to send a delay control signal;
the input end of a feedback switch tube Q3 and the input end of a feedback switch tube Q3 are connected with the homodromous input end of a second comparator CMP2, the output end of the feedback switch tube Q3 is grounded, and the grid electrode of a feedback switch tube Q3 is connected with the output end of a D-type trigger DFF.
Specifically, to generate a relatively stable delay control signal, in this embodiment, the constant current source I0 is set to charge the delay capacitor C1, after the charging of the delay capacitor C1 is completed, the equidirectional input end of the second comparator CMP2 is changed to a high level, and the level is higher than the inductance peak current input by the current sensor Isense, at this time, the second comparator CMP2 outputs the high level to turn over the class D flip-flop DFF, and the feedback switch tube Q3 is turned on and discharged, thereby completing the generation process of a delay signal.
In a preferred embodiment, the second output of the current sensor Isense is connected to ground through a pull-down resistor R1.
Generating the delay control signal to control the converter circuit based on the above process, the time for the inductor L1 to discharge to zero is only related to the magnitude of its peak current:
Figure BDA0003763949600000081
wherein, U is the voltage of the delay capacitor C1 at the end of charging, L is the inductance of the inductor L1, and t is the time from the inductor L1 to zero discharge, which is equivalent to the zero-crossing time of the inductor current, I, collected in the prior art max The peak current of the inductor L1.
Meanwhile, in the above process, the discharge time of the feedback switch tube depends on the charging duration of the delay capacitor C1, and then:
Figure BDA0003763949600000082
wherein, t dly For the discharge time of the feedback switch tube Q3, C is the capacitance of the delay capacitor C1, R is the resistance of the pull-down resistor R1, I 0 Is the output current of a constant current source I0 max The peak current of the inductor L1.
In order to realize that the above discharging process is consistent with the time when the inductor L1 discharges to zero, the discharging process can be realized by adjusting the capacitance of the delay capacitor C2, and includes:
Figure BDA0003763949600000091
wherein C is the capacitance of the delay capacitor C2, R is the resistance of the pull-down resistor R1, I 0 Is the output current of a constant current source, I max The peak current of the inductor L1.
In a preferred embodiment, the voltage sensing module 3 comprises:
a reference voltage source Vref;
the same-direction input end of the third comparator CMP3 and the same-direction input end of the third comparator CMP3 are connected with the output end of the reference voltage source Vref, and the reverse-direction input end of the third comparator CMP3 is connected with the input end of the voltage sensing module 3.
In a preferred embodiment, the logic controller operates in PFM mode.
Fig. 3 is a voltage timing diagram of the present invention, and it can be seen from the diagram that a better output effect can be achieved by sequentially transmitting a current control signal, a delay control signal, and a voltage control signal.
The invention has the beneficial effects that: the current sensing module is provided with the delay unit to replace a zero crossing point comparator in the prior art, and the output module can be discharged by controlling the generation of the delay control signal under the relatively stable output condition, so that the problem that the peak current of the inductor is mistakenly triggered due to the shaking of the grounding end by grounding and sensing in the prior art is solved, and the relatively stable output effect is realized.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims (8)

1. A buck dc converter, comprising:
the input end of the output module is connected with the power supply circuit, and the output end of the output module is connected with the load circuit;
the input end of the current sensing module is connected with the current feedback end and the first voltage feedback end of the output module, the output end of the current sensing module is connected with the control end of the output module, the current sensing module obtains peak current and first feedback voltage from the output module, and generates a current control signal according to the peak current and the first feedback voltage;
the current sensing module is also provided with a delay unit, and the delay unit generates a delay control signal according to the peak current;
the input end of the voltage sensing module is connected with the second voltage feedback end of the output module, the output end of the voltage sensing module is connected with the control end of the output module, and the voltage sensing module acquires second feedback voltage from the output module and generates a voltage control signal according to the second feedback voltage;
the output module obtains electricity from the power supply circuit according to the control of the current control signal, the delay control signal and the voltage control signal, and outputs output current to the load circuit.
2. The buck dc converter according to claim 1, wherein the output module includes:
a power input end of the control unit is an input end of the output module, a signal input end of the control unit is a control end of the output module, and the control unit receives the current control signal, the voltage control signal and the delay control signal respectively;
the first end of the inductor is connected with the output end of the control unit, and the second end of the inductor is the output end of the output module;
a first end of the output capacitor is connected with a second end of the inductor, and a second end of the output capacitor is grounded;
the first end of the inductor is a first voltage feedback end of the output module, and the second end of the inductor is a second voltage feedback end of the output module.
3. The buck dc converter according to claim 2, wherein the control unit includes:
a logic controller that receives the current control signal, the voltage control signal, and the delay control signal, respectively;
the input end of the first switch tube is connected with the power supply circuit, and the output end of the first switch tube is the output end of the output module;
the input end of the second switch tube is connected with the output end of the first switch tube, and the output end of the second switch tube is grounded;
a first control end of the logic controller is connected with the grid electrode of the first switching tube, and a second control end of the control unit is connected with the grid electrode of the second switching tube;
the logic controller respectively controls the first switch tube and the second switch tube according to the current control signal, the voltage control signal and the time delay control signal.
4. The buck dc converter according to claim 2, wherein the current sensing module includes:
the current sensor acquires peak current on the inductor and generates peak voltage output according to the peak current;
the same-direction input end of the first comparator is connected with the input end of the current sensing module, the reverse-direction input end of the first comparator is connected with the first output end of the current sensor, and the output end of the first comparator is connected with the output module to send the current control signal;
the first input end of the delay unit is connected with the output end of the first comparator, the second input end of the delay unit is connected with the second output end of the current sensor, and the output end of the delay unit is connected with the output module to send the delay control signal.
5. The buck dc converter according to claim 1, wherein the delay unit comprises:
the output end of the constant current source is connected with the first end of the delay capacitor, and the second end of the delay capacitor is grounded;
the same-direction input end of the second comparator is connected with the first end of the delay capacitor, and the reverse-direction input end of the second comparator is connected with the output end of the current sensor;
a clock input end of the D-type trigger is connected with an output end of the first comparator, a data input end of the D-type trigger is at a high level, and an output end of the D-type trigger is connected with the output module to send the delay control signal;
the input end of the feedback switch tube is connected with the homodromous input end of the second comparator, the output end of the feedback switch tube is grounded, and the grid electrode of the feedback switch tube is connected with the output end of the D-type trigger.
6. The buck dc converter according to claim 4, wherein the second output of the current sensor is coupled to ground through a pull-down resistor.
7. The buck dc converter according to claim 1, wherein the voltage sensing module includes:
a reference voltage source;
and the same-direction input end of the third comparator is connected with the output end of the reference voltage source, and the reverse-direction input end of the third comparator is connected with the input end of the voltage sensing module.
8. The buck dc converter according to claim 3, wherein the logic controller operates in a PFM mode.
CN202210880236.3A 2022-07-25 2022-07-25 Step-down DC converter Pending CN115085550A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116995936A (en) * 2023-09-22 2023-11-03 茂睿芯（深圳）科技有限公司 Power supply adjusting circuit, buck converter and direct current power supply

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116995936A (en) * 2023-09-22 2023-11-03 茂睿芯（深圳）科技有限公司 Power supply adjusting circuit, buck converter and direct current power supply
CN116995936B (en) * 2023-09-22 2024-03-01 茂睿芯（深圳）科技有限公司 Power supply adjusting circuit, buck converter and direct current power supply

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