CN115065253B - Valley bottom locking control method of flyback switching power supply and related device - Google Patents

Valley bottom locking control method of flyback switching power supply and related device Download PDF

Info

Publication number
CN115065253B
CN115065253B CN202210995766.2A CN202210995766A CN115065253B CN 115065253 B CN115065253 B CN 115065253B CN 202210995766 A CN202210995766 A CN 202210995766A CN 115065253 B CN115065253 B CN 115065253B
Authority
CN
China
Prior art keywords
valley
peak current
pin
signal
input end
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202210995766.2A
Other languages
Chinese (zh)
Other versions
CN115065253A (en
Inventor
朱况
陈伟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen Injoinic Technology Co Ltd
Original Assignee
Shenzhen Injoinic Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenzhen Injoinic Technology Co Ltd filed Critical Shenzhen Injoinic Technology Co Ltd
Priority to CN202210995766.2A priority Critical patent/CN115065253B/en
Priority to CN202211471529.2A priority patent/CN115940653A/en
Publication of CN115065253A publication Critical patent/CN115065253A/en
Priority to PCT/CN2022/132278 priority patent/WO2024036789A1/en
Application granted granted Critical
Publication of CN115065253B publication Critical patent/CN115065253B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33507—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters
    • H02M3/33523—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of the output voltage or current, e.g. flyback converters with galvanic isolation between input and output of both the power stage and the feedback loop
    • 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
    • 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
    • H02M1/44—Circuits or arrangements for compensating for electromagnetic interference in converters or inverters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Landscapes

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

Abstract

The application provides a valley bottom locking control method and a related device of a flyback switching power supply, wherein the control device comprises a valley bottom detection module, a valley bottom number counting module, a peak current control module and a PWM (pulse width modulation) logic module; the valley bottom detection module detects valley bottoms in the working process of the converter, the valley bottom number counting module compares and counts peak current reference signals to obtain reference valley numbers, the peak current control module obtains the peak current reference signals according to the feedback voltage and the reference valley numbers, specifically, after the reference valley numbers are changed, the corresponding relation between the peak current reference signals and the feedback voltage is adjusted, and the PWM logic module generates PWM pulses for driving the main power switch tube. The embodiment of the application realizes the valley bottom locking function of the converter, enables the working power of the converter at the valley switching point to be approximately equal, and improves the dynamic performance of the converter.

Description

Valley bottom locking control method of flyback switching power supply and related device
Technical Field
The application relates to the technical field of electronics, in particular to a valley bottom locking control method and a related device of a flyback switching power supply.
Background
The flyback switching power supply is also called as a flyback converter, a switching tube of the flyback switching power supply has larger parasitic capacitance, and when the working voltage of the switching tube is higher, the converter has larger switching loss. Therefore, in order to improve the operating efficiency of the converter, the flyback converter generally turns on the resonant valley in the DCM mode, where the voltage across the drain and the source of the switching tube is the minimum, and the switching loss of the switching tube is also reduced to the minimum, and the flyback converter operating in this mode is called a quasi-resonant (QR) flyback converter.
In practical applications, the operating frequency of the switching power supply operating in the QR mode is inversely proportional to the load, and therefore, the prior art generally uses a maximum frequency clamp to limit the operating frequency range of the switching power supply. However, when the number of the converter valley bottoms changes, the relationship between the peak current reference signal and the feedback voltage does not change, so that the peak current reference signal of the converter at the working point of valley bottom number switching does not change, but the working frequency changes suddenly, so that the output power of the converter changes suddenly, and the dynamic performance of the system is influenced; meanwhile, the working power of the flyback converter is discontinuous, the converter jumps between two or even a plurality of valleys, the working frequency of the converter fluctuates greatly, the EMI performance of a system is affected, and audible noise is generated. Therefore, how to implement the valley locking function of the flyback converter is urgently needed to be solved.
Disclosure of Invention
The embodiment of the application provides a valley bottom locking control method and a related device of a flyback switching power supply, which can realize the valley bottom locking function of a flyback converter.
In a first aspect, an embodiment of the present application provides a valley locking control device for a flyback switching power supply, where the control device includes: the peak current control module is also connected with the valley bottom number counting module, the valley bottom detection module is connected with a first pin of the control device, the PWM logic module is connected with a second pin and a third pin of the control device, and the peak current control module is connected with a fourth pin of the control device;
the valley bottom detection module is used for detecting valley bottoms in the working process of the converter;
the valley bottom number counting module is used for comparing and counting the peak current reference signals to obtain a reference Gu Zhishu when the main power switch tube is switched on;
the peak current control module is configured to obtain a peak current reference signal when the main power switch is turned off according to a feedback voltage and the reference Gu Zhishu, specifically, after the number of reference valleys is changed, adjust a corresponding relationship between the peak current reference signal and the feedback voltage, where the peak current reference signal decreases by an offset when the number of reference valleys decreases, or the peak current reference signal increases by an offset when the number of reference valleys increases;
the PWM logic module is used for generating PWM pulses for driving the main power switch tube according to a valley bottom signal, the reference Gu Zhishu, the peak current reference signal and a pin voltage signal of the third pin.
In a second aspect, an embodiment of the present application provides a valley lock control method for a flyback switching power supply, which is applied to the valley lock control device for the flyback switching power supply described in the first aspect, and the method includes:
the valley bottom detection module detects valley bottoms in the working process of the converter;
the valley bottom number counting module compares and counts the peak current reference signal to obtain a reference Gu Zhishu when the main power switch tube is switched on;
the peak current control module obtains a peak current reference signal when the main power switch tube is turned off according to the feedback voltage and the reference Gu Zhishu, specifically, after the number of reference valleys is changed, the corresponding relation between the peak current reference signal and the feedback voltage is adjusted, when the number of reference valleys is reduced, the peak current reference signal is reduced by an offset, or when the number of reference valleys is increased, the peak current reference signal is increased by an offset;
the PWM logic module is used for generating PWM pulses for driving the main power switch tube according to a valley bottom signal, the reference Gu Zhishu, the peak current reference signal and a pin voltage signal of the third pin.
In a third aspect, embodiments of the present application provide a charger including the control device as described in the first aspect.
The embodiment of the application has the following beneficial effects:
it can be seen that, in the valley bottom locking control method and the related device of the flyback switching power supply described in the embodiment of the present application, the valley bottom detection module detects the valley bottom in the working process of the converter; the valley bottom number counting module compares and counts the peak current reference signal to obtain a reference Gu Zhishu when the main power switch tube is switched on; the peak current control module obtains a peak current reference signal when the main power switch tube is turned off according to the feedback voltage and the reference valley number, specifically, after the reference valley number is changed, the corresponding relation between the peak current reference signal and the feedback voltage is adjusted, the peak current reference signal decreases by an offset when the reference valley number decreases, or the peak current reference signal increases by an offset when the reference valley number increases, and the PWM logic module is configured to generate a PWM pulse for driving the main power switch tube according to the valley signal, the reference Gu Zhishu, the peak current reference signal, and a pin voltage signal of the third pin. Therefore, the embodiment of the application not only enables the transmission power between adjacent valley bottoms of the converter to be overlapped to achieve the purpose of locking the valley, but also enables the output power of the converter not to fluctuate violently when the valley bottoms are switched, and improves the dynamic performance of the system.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic operating frequency diagram of a frequency clamp control method in the related art according to an embodiment of the present application;
fig. 2 is a graph of a relationship between a peak current signal and a feedback voltage signal in a frequency clamp control method according to an embodiment of the present application;
fig. 3 is a schematic operating power diagram of a frequency clamp control method in the related art according to an embodiment of the present application;
fig. 4 is a schematic diagram of a valley locking control device of a flyback switching power supply according to an embodiment of the present disclosure;
fig. 5 is a schematic circuit diagram of another flyback switching power supply system provided in the embodiment of the present application;
fig. 6 is a schematic circuit diagram of another flyback switching power supply system provided in the embodiment of the present application;
fig. 7 is a schematic structural diagram of a valley bottom counting module according to an embodiment of the present disclosure;
FIG. 8 is a graph of a valley number signal versus a feedback voltage signal provided by an embodiment of the present application;
FIG. 9 is a schematic diagram of a peak current control module according to an embodiment of the present disclosure;
FIG. 10 is a graph of a peak current signal versus a feedback voltage signal provided by an embodiment of the present application;
FIG. 11 is a schematic structural diagram of a PWM logic module according to an embodiment of the present disclosure;
FIG. 12 is a schematic diagram of operating power provided by an embodiment of the present application;
fig. 13 is a schematic flowchart of a valley locking control method of a flyback switching power supply according to an embodiment of the present application.
Detailed Description
In order to better understand the technical solutions of the present application, the following description is given for clarity and completeness in conjunction with the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments obtained by a person skilled in the art without making any inventive step on the basis of the description of the embodiments of the present application belong to the protection scope of the present application.
The terms "first," "second," and the like in the description and claims of the present application and in the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, software, product, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements recited, but may also include other steps or elements not expressly listed or inherent to such process, method, product, or apparatus.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.
The embodiments of the present application will be described with reference to the drawings, in which a dot at the intersection of intersecting wires indicates that the wires are connected, and a dot-free intersection indicates that the wires are not connected.
In order to better understand the scheme of the embodiments of the present application, the following first introduces the related terms and concepts that may be involved in the embodiments of the present application.
In the related art, as shown in fig. 1, which is a schematic diagram of an operating frequency of a conventional frequency clamp control method, as shown in fig. 2, which is a graph of a relationship between a peak current reference signal and a feedback voltage signal of the conventional control method, and as shown in fig. 3, which is a schematic diagram of an operating power of the conventional frequency clamp control method, when a valley switching operating point of a flyback converter is close to, the operating power of the flyback converter suddenly changes, and the operating power is discontinuous, so that the converter may frequently switch to the valley when the load power is at the discontinuous operating power point. The specific reasons are as follows: if the load is in steady state, the load power is just at the power interruption point, such as P in FIG. 3 1 And at the corresponding power point, the working power of the converter at the first valley bottom is greater than the load power, and the working power of the converter at the second valley bottom is less than the load power, so that the converter can be repeatedly switched under two working states of the first valley bottom and the second valley bottom to enable the output average power to be equal to the load power.
To solve the drawbacks of the related art, please refer to fig. 4, where fig. 4 is a schematic structural diagram of a valley-locked control device of a flyback switching power supply according to an embodiment of the present application, the control device includes: the peak current control module is also connected with the valley bottom number counting module, the valley bottom detection module is connected with a first pin VS of the control device, the PWM logic module is connected with a second pin VG and a third pin CS of the control device, and the peak current control module is connected with a fourth pin FB of the control device;
the valley bottom detection module is used for detecting valley bottoms in the working process of the converter;
the valley bottom number counting module is used for comparing and counting the peak current reference signals to obtain a reference Gu Zhishu when the main power switch tube is switched on;
the peak current control module is configured to obtain a peak current reference signal when the main power switch is turned off according to a feedback voltage and the reference Gu Zhishu, specifically, after the number of reference valleys is changed, adjust a corresponding relationship between the peak current reference signal and the feedback voltage, where the peak current reference signal decreases by an offset when the number of reference valleys decreases, or the peak current reference signal increases by an offset when the number of reference valleys increases;
the PWM logic module is used for generating PWM pulses for driving the main power switch tube according to a valley signal, the reference Gu Zhishu, the peak current reference signal and a pin voltage signal of the third pin.
In a specific implementation, the control device may include a valley bottom detection module, a valley bottom number counting module, a peak current control module, and a PWM logic module. The peak current control module obtains a peak current reference signal when the main power switch tube is turned off according to feedback voltage and the reference valley number, specifically, after the reference valley number is changed, the corresponding relation between the peak current reference signal and feedback voltage is adjusted, the peak current reference signal is reduced by an offset when the reference valley number is reduced, or the peak current reference signal is increased by an offset when the reference valley number is increased, and the PWM logic module generates PWM pulses for driving the main power switch tube according to the valley signal, the reference Gu Zhishu, the peak current reference signal and a CS pin voltage signal.
The comparison value of the peak current reference signal, namely the valley adding reference voltage and the valley reducing reference voltage, is set to have larger hysteresis so that the power between two adjacent valley bottoms is superposed to realize the valley bottom locking of the converter; the increased or decreased offset should make the operating powers of the converters at the valley bottom number switching points approximately equal, that is, the difference between the operating powers of the two is smaller than a preset threshold, the preset threshold may be preset or default to the system, the preset threshold may be close to 0, for example, the preset threshold is 0.1, and for example, the preset threshold is 0.01, that is, the operating power difference between the two is ensured to be as small as possible, so as to improve the dynamic performance of the converter.
In this embodiment, the valley bottom number counting module may include a selector, and select the corresponding valley adding and valley reducing reference voltages according to the reference Gu Zhishu through the selector, input the reference voltages into the comparator, compare the peak current reference signal with the valley adding and valley reducing reference voltages, count the comparison result after the switching tube is turned on, and obtain the reference valley value number when the main power switching tube in the next period is turned on after counting.
In a specific implementation, the converter counts the valley bottoms after the main power switch tube is turned off, and the switch tube is turned on only when the counted valley bottoms is equal to reference Gu Zhishu.
Optionally, the first pin VS is used for connecting a converter, the converter includes an auxiliary winding, a primary winding, and a secondary winding, one end of the auxiliary winding is connected to the first pin VS, and the other end is grounded; one end of the primary winding is connected with an external power supply, and the other end of the primary winding is connected with the first end of the main power switch tube Q1; one end of the secondary winding is connected with one end of the diode, and the other end of the secondary winding is grounded; the other end of the diode D1 is connected with the fourth pin FB through a feedback and isolation module;
the PWM logic module is connected with the second end of the main power switch tube Q1 through the second pin VG, and the PWM logic module is connected with the third end of the main power switch tube Q1 through the third pin CS and is connected with the sampling resistor R sense And (4) grounding.
Wherein, as shown in FIG. 5, the first leadThe pin VS is used for connecting a converter, the converter comprises an auxiliary winding, a primary winding and a secondary winding, one end of the auxiliary winding is connected with the first pin VS, and the other end of the auxiliary winding is grounded; one end of the primary winding is connected with an external power supply, and the other end of the primary winding is connected with the first end of the main power switch tube Q1; one end of the secondary winding is connected with one end of the diode D1, and the other end of the diode D1 is grounded; the other end of the diode D1 is connected with a fourth pin FB through a feedback and isolation module; the PWM logic module is connected with the second end of the main power switch tube Q1 through a second pin VG, and is connected with the third end of the main power switch tube Q1 through a third pin CS and passes through a sampling resistor R sense And (4) grounding.
In a specific implementation, the current magnitude may be sampled by sampling a voltage of a resistor.
Wherein, one end of the primary winding can also pass through a capacitor (C) in ) The output end of the diode D1 can also pass through a capacitor (C) by being grounded o ) And (4) grounding.
Optionally, the first pin VS is used for connecting the converter, and the converter includes an auxiliary winding, a primary winding, and a secondary winding;
one end of the auxiliary winding is connected with the first pin VS, and the other end of the auxiliary winding is grounded; one end of the primary winding is connected with an external power supply, and the other end of the primary winding is connected with the MOS integrated system; one end of the secondary winding is connected with one end of the diode D1, and the other end of the diode D1 is grounded; the other end of the diode is connected with the fourth pin FB through a feedback and isolation module;
the PWM logic module is connected with the MOS integrated system through the second pin VG and the third pin CS, and the MOS integrated system comprises a main power switch tube.
In a specific implementation, as shown in fig. 6, the first pin VS is used for connecting a converter, and the converter includes an auxiliary winding, a primary winding, and a secondary winding; one end of the auxiliary winding is connected with the first pin VS, and the other end of the auxiliary winding is grounded; one end of the primary winding is connected with an external power supply (V) in ) And the other end is connected with an MOS integrated System (Mosfet System); one end of the secondary winding is connected with one end of the diode D1, and the other end of the diode D1 is grounded; the other end of the diode is connected with the isolation module through feedbackIs connected with a fourth pin FB; the PWM logic module is connected with an MOS integrated system through a second pin VG and a third pin CS, and the MOS integrated system comprises a main power switch tube.
Wherein, one end of the primary winding can also pass through a capacitor (C) in ) The output end of the diode D1 can also pass through a capacitor (C) by being grounded o ) And (4) grounding.
In specific implementation, the MOS can be integrated into a small system, i.e., a MOS integrated system, and the system can directly output a voltage signal reflecting the magnitude of current without adding a sampling resistor.
In the embodiment of the application, after the peak current reference signals are compared and counted, the reference valley number when the main power switch tube is switched on is obtained, the peak current reference signal when the main power switch tube is switched off is obtained according to the feedback voltage and the reference valley number, namely, the relation between the peak current reference signal and the feedback voltage is adjusted under the condition of different reference valley numbers, so that the transmission power between adjacent valleys of the converter is overlapped, the valley locking purpose is achieved, the output power of the converter cannot fluctuate violently when the valleys are switched, and the dynamic performance of the system is improved.
Optionally, the Valley bottom detecting module is configured to sample a pin voltage of the first pin VS, detect a Valley bottom of the converter during a working process, generate a Valley bottom signal Valley, and transmit the generated Valley bottom signal Valley to the PWM logic module;
the valley bottom number counting module is used for counting the peak current reference signal V cs_ref After comparison and counting, obtaining a reference Valley number Valley _ N when the main power switch tube is switched on, and transmitting the reference Gu Zhishu Valley _ N to the peak current control module and the PWM logic module;
the peak current control module is used for controlling the peak current according to the feedback voltage signal V of the fourth pin FB FB And the reference Valley number Valley _ N is used for obtaining the peak current reference signal V when the main power switch tube is turned off cs_ref Specifically, after the reference Valley number Valley _ N is changed, the peak current is adjustedThe peak current is referred to as V when the reference Valley number Valley _ N is reduced according to the corresponding relationship between the reference signal and the feedback voltage cs_ref The signal is decreased by an offset, or the peak current reference signal V is increased when the reference Valley number Valley _ N is increased cs_ref Adding an offset to the peak current reference signal V cs_ref Transmitting the number to the valley bottom counting module and the PWM logic module;
the PWM logic module is used for receiving the Valley signal, the reference Valley number Valley _ N when the main power switch tube is switched on, and the peak current reference signal V cs_ref And a pin voltage signal V of the third pin CS cs Generating PWM pulses for driving the main power switch tube, specifically: when the number of the bottom signals is equal to the reference valley value number, the PWM logic module outputs a high level; when the pin voltage signal is greater than the peak current reference signal, the PWM logic module outputs a low level, and a PWM pulse signal is output through the second pin.
In a specific implementation, the valley bottom number counting module is used for counting a peak current reference signal V cs_ref And after comparison and counting, obtaining a reference Valley number Valley _ N when the main power switch tube is switched on, and transmitting the reference Valley number Valley _ N to the peak current control module and the PWM logic module. The peak current control module is used for controlling the peak current according to a feedback voltage signal V of the FB pin FB And the reference Valley number Valley _ N obtains a peak current reference signal V when the main power switch tube is turned off cs_ref Specifically, after the number of reference valleys is changed, the corresponding relationship between the peak current reference signal and the feedback voltage is adjusted, the peak current reference signal decreases by an offset when the number of reference valleys decreases or increases by an offset when the number of reference valleys increases, and the peak current reference signal V is adjusted cs_ref And the number is transmitted to a valley bottom number counting module and a PWM logic module.
The PWM logic module is used for providing a Valley signal Valley, a reference Gu Zhishu Valley _ N when the main power switch tube is switched on and a peak current reference signal V cs_ref And CS Pin Voltage Signal V cs Generating PWM pulses for driving a main power switch tube, specifically, when the number of the counted valley bottom signals is equal to reference Gu Zhishu, outputting a high level by a PWM logic module; when the voltage signal of the CS pin is larger than the peak current reference signal, the PWM logic module outputs low level, and the PWM pulse signal is output through the VG pin.
Optionally, the valley bottom number counting module includes a first selector, a second selector, a first comparator, a second comparator, an exclusive or gate, and a counter;
the data input end of the first selector is respectively connected with P valley reference voltages, the data input end of the second selector is respectively connected with P valley reference voltages, and P is an integer greater than 1;
the reference valley number is connected to the data selection ends of the first selector and the second selector, the data output ends of the first selector and the second selector are respectively connected to the positive input end of the first comparator and the negative input end of the second comparator, the peak current reference signal is connected to the negative input end of the first comparator and the positive input end of the second comparator, the output end of the first comparator is connected to one input end of the exclusive-or gate and the Add end of the counter, the output end of the second comparator is connected to the other input end of the exclusive-or gate and the Sub end of the counter, the output end of the exclusive-or gate is connected to the enable end of the counter, the clock input end of the counter is connected to the main power switch tube turn-on signal, and the output end of the counter outputs the reference valley number.
The selector selects corresponding valley adding and valley reducing reference voltages according to the reference Gu Zhishu, the reference voltages are input into the comparator, the peak current reference signals are compared with the valley adding and valley reducing reference voltages to obtain peak current reference signal comparison values, namely comparison results, the comparison results are counted after the main power switch tube is turned on, and the reference valley value number when the main power switch tube is turned on in the next period is obtained after counting.
In a specific implementation, as shown in fig. 7, the valley bottom number counting module may include a first selector, a second selector, a first comparator, and a second comparatorA comparator, an exclusive-or gate and a counter. The data input end of the first selector is respectively connected with Valley adding reference voltages a, b, c, d and e, the data input end of the second selector is respectively connected with Valley reducing reference voltages A, B, C, D, E, the reference Valley number Valley _ N is connected with the data selection ends of the first selector and the second selector, the data output ends of the first selector and the second selector are respectively connected with the positive input end of the first comparator and the negative input end of the second comparator, and the peak current reference signal V is cs_ref The negative input end of the first comparator and the positive input end of the second comparator are connected, the output end of the first comparator is connected with one input end of the exclusive-OR gate and the Add end of the counter, the output end of the second comparator is connected with the other input end of the exclusive-OR gate and the Sub end of the counter, the output end of the exclusive-OR gate is connected with the enable end EN of the counter, the clock input end of the counter is connected with a main power switch tube on signal (Drive _ on), and the output end of the counter outputs reference Gu Zhishu (Valley _ N).
In the specific implementation, as shown in fig. 8, it can be seen that the specific working process of the valley bottom number counting module is as follows: the selector selects corresponding valley adding and valley reducing reference voltages according to the reference Gu Zhishu, inputs the reference voltages into the comparator, and outputs a peak current reference signal V cs_ref And comparing with the Valley adding reference voltage and the Valley reducing reference voltage, counting the comparison result after the main power switch tube is switched on, and obtaining the reference Valley value number Valley _ N when the main power switch tube is switched on in the next period after counting.
Optionally, the peak current control module includes a third selector and a subtractor; the data input end of the third selector is respectively connected with Q reference signals, and Q is an integer greater than 1;
the data selection end of the third selector is connected with the reference Gu Zhishu, the output end of the third selector is connected with the negative input end of the subtracter, and the third selector selects a corresponding reference signal according to the reference valley number and outputs the selected reference signal to the negative input end of the subtracter; the feedback voltage signal is connected with the positive input end of the subtracter and the subtracter outputs the peak current reference signal through a preset proportion link.
As shown in fig. 9, the peak current control module includes a third selector, a subtractor, and a proportion element; the data input ends of the third selectors are respectively connected with the reference signal V ref1 、V ref2 、V ref3 、V ref4 、V ref5 And V ref6 The data selection end of the selector is connected with the reference Valley number Valley _ N, the output end of the selector is connected with the negative input end of the subtracter, and the selector selects a corresponding reference signal according to the reference Gu Zhishu Valley _ N and outputs the selected reference signal to the negative input end of the subtracter; feedback voltage signal V FB The positive input end of the subtracter and the output end of the subtracter are connected with a proportional element (1/K) v ) The output end of the proportional link outputs a peak current reference signal V cs_ref 。
In a specific implementation, as shown in fig. 10, the peak current control module specifically works as follows: the selector selects a corresponding reference signal according to the reference Gu Zhishu Valley _ N, and the peak current reference signal V can be obtained according to the selected reference signal and a preset proportionality coefficient cs_ref Thus, after the reference valley value number is changed, the corresponding relation between the peak current reference signal and the feedback voltage, V, is adjusted cs_ref Can be obtained by the following formula:
Figure 928825DEST_PATH_IMAGE001
in which V is ref A reference voltage selected for the selector.
Optionally, the PWM logic module includes a digital counter, a digital comparator, an and gate, a third comparator, an R/S flip-flop, and a single pulse flip-flop;
the data input end of the digital counter is connected with the valley bottom signal, the reset input end of the digital counter is connected with the main power switch tube opening signal, the digital counter counts the valley bottom quantity of the current period according to the valley bottom signal, and the digital counter is reset when the main power switch tube is opened;
the first input end of the digital comparator is connected with the output end of the digital counter;
the second input end of the digital comparator is connected with the valley bottom number signal, and the digital comparator outputs high level when the first input end is larger than or equal to the second input end; the first input end of the AND gate is connected with the valley bottom signal, and the second input end of the AND gate is connected with the output end of the digital comparator; the positive input end of the third comparator is connected with the pin voltage signal of the third pin, and the negative input end of the third comparator is connected with the peak current reference signal; the set end of the R/S trigger is connected with the output end of the AND gate, and the reset end of the R/S trigger is connected with the output end of the third comparator; the output end of the R/S trigger outputs a driving signal and is connected with the input end of the single pulse trigger, the output end of the single pulse trigger outputs a main power switch tube turn-on signal, when a pin voltage signal of the third pin is larger than the peak current reference signal, the third comparator outputs a high level, the R/S trigger is reset, the driving signal is changed into a low level, when the digital comparator outputs a high level and the valley bottom signal is also a high level, the AND gate outputs a high level, the R/S trigger is set, and the driving signal is changed into a high level.
As shown in fig. 11, the PWM logic module includes a digital counter, a digital comparator, an and gate, a third comparator, an R/S flip-flop, and a single pulse flip-flop; the data input end of the digital counter is connected with a Valley bottom signal Valley, the reset input end of the digital counter is connected with a switching tube on signal Drive _ on, the digital counter counts the Valley bottom quantity of the current period according to the Valley bottom signal, and the digital counter is reset when the switching tube is on; a first input end of the digital comparator is connected with an output end of the digital counter, a second input end of the digital comparator is connected with the Valley bottom number signal Valley _ N, and the digital comparator outputs high level when the first input end is larger than or equal to the second input end; the first input end of the AND gate is connected with the Valley bottom signal Valley, and the second input end of the AND gate is connected with the output end of the digital comparator; the positive input end of the third comparator is connected with a CS pin voltage signal V cs The negative input end of the third comparator is connected with the peak current parameterExamination signal V cs_ref (ii) a The output end of the single-pulse trigger outputs a switching tube on signal Drive _ on, and a voltage signal V at a CS pin cs Greater than peak current reference signal V cs_ref When the third comparator outputs a high level, the R/S flip-flop is reset, the Drive signal Drive becomes a low level, and when the digital comparator outputs a high level and the Valley signal Valley is also a high level, the and gate outputs a high level, the R/S flip-flop is set, and the Drive signal Drive becomes a high level.
In specific implementation, the PWM logic module specifically works as follows: the digital counter counts the Valley bottom number of the current period according to the Valley bottom signal, the digital counter is reset when the switch tube is switched on, the digital comparator outputs high level when the Valley bottom number Count _ N counted by the digital counter is more than or equal to the reference Valley value number Valley _ N, and the voltage signal V is output at the CS pin cs Greater than peak current reference signal V cs_ref When the third comparator outputs a high level, the R/S flip-flop is reset, the driving signal Drive becomes a low level, when the digital comparator outputs a high level and the Valley signal Valley is also a high level, the and gate outputs a high level, the R/S flip-flop is set, and the driving signal Drive becomes a high level.
Optionally, the voltage signal of the third pin is a voltage signal reflecting the current of the power loop, and the voltage signal is obtained by sampling voltages at two ends of an external sampling resistor, or is obtained by directly sampling a voltage signal reflecting the current of the power loop.
In a specific implementation, in the circuits shown in fig. 5 and 6, after the switching tube is turned on, the current flowing through the switching tube gradually rises, the current is the power loop current, and the third pin CS samples the current.
Further, as shown in fig. 12, compared with the control method in the related art, the reference valley number when the converter is turned on is obtained by comparing and counting the peak current reference signals, and the comparison value of the peak current reference signals, i.e., the valley adding reference voltage and the valley reducing reference voltage, can set a larger hysteresis so that the power between two adjacent valley bottoms is overlapped, thereby enabling valley bottom locking to be achieved; meanwhile, after the reference valley number is changed, the relation between the peak current reference signal and the feedback voltage is adjusted, specifically, when the reference valley number is reduced, the peak current reference signal is reduced by an offset or when the reference valley number is increased, the peak current reference signal is increased by an offset, so that the working power of the converter at the valley bottom number switching point is approximately equal, and the dynamic performance of the converter is improved.
In the embodiment of the application, after the peak current reference signals are compared and counted, the reference Gu Zhishu when the main power switch tube is switched on is obtained; the corresponding relation between the peak current reference signal and the feedback voltage can be adjusted after the reference valley number is changed, specifically, when the reference valley number is reduced, the peak current reference signal is reduced by an offset or when the reference valley number is increased, the peak current reference signal is increased by an offset, namely, the relation between the peak current reference signal and the feedback voltage is adjusted under the condition of different reference valley numbers, so that the transmission power between adjacent valley bottoms of the converter is overlapped, the valley locking purpose is achieved, the output power of the converter is not severely fluctuated when the valley bottoms are switched, and the dynamic performance of a system is improved.
Please refer to fig. 13, fig. 13 is a schematic flow chart of a valley bottom locking control method of a flyback switching power supply according to an embodiment of the present application, which is applied to the valley bottom locking control device of the flyback switching power supply according to the embodiment of the present application, and includes the following steps:
s1, the valley bottom detection module detects valley bottoms in the working process of the converter;
s2, comparing and counting the peak current reference signals by the valley bottom number counting module to obtain a reference Gu Zhishu when the main power switch tube is switched on;
s3, the peak current control module obtains a peak current reference signal when the main power switch tube is turned off according to the feedback voltage and the reference Gu Zhishu, specifically, after the reference valley number is changed, the corresponding relation between the peak current reference signal and the feedback voltage is adjusted, when the reference valley number is reduced, the peak current reference signal is reduced by an offset, or when the reference valley number is increased, the peak current reference signal is increased by an offset;
and S4, the PWM logic module is used for generating PWM pulses for driving the main power switch tube according to a valley signal, the reference Gu Zhishu, the peak current reference signal and a pin voltage signal of the third pin.
For the specific description of the steps S1 to S4, reference may be made to the corresponding description above, and details are not repeated here.
In the embodiment of the application, a charger can be further provided, and the charger comprises the control device, valley bottom locking is realized through the control device, the maximum working frequency of the switching power supply is limited, and the stability of the charger is ensured.
The foregoing is an implementation of the embodiments of the present application, and it should be noted that, for those skilled in the art, several modifications and decorations can be made without departing from the principle of the embodiments of the present application, and these modifications and decorations are also regarded as the protection scope of the present application.

Claims (10)

1. A valley locking control device of a flyback switching power supply, the control device comprising: the peak current control module is also connected with the valley bottom number counting module, the valley bottom detection module is connected with a first pin VS of the control device, the PWM logic module is connected with a second pin VG and a third pin CS of the control device, and the peak current control module is connected with a fourth pin FB of the control device;
the valley bottom detection module is used for detecting valley bottoms in the working process of the converter;
the valley bottom number counting module is used for comparing and counting the peak current reference signal with valley addition and valley reduction reference voltages to obtain the reference valley value number when the main power switch tube is switched on, and the valley addition and valley reduction reference voltages enable output power between two adjacent valley bottoms of the converter to be superposed by setting larger hysteresis so as to realize the valley bottom locking function of the converter;
the peak current control module is configured to obtain a peak current reference signal when the main power switch is turned off according to a feedback voltage and the reference Gu Zhishu, specifically, after the number of reference valleys is changed, adjust a corresponding relationship between the peak current reference signal and the feedback voltage, where the peak current reference signal decreases by an offset when the number of reference valleys decreases, or the peak current reference signal increases by an offset when the number of reference valleys increases, so that output powers of the converter at valley bottom number switching points are approximately equal, and dynamic performance of the converter is improved;
the PWM logic module is used for generating PWM pulses for driving the main power switch tube according to a valley signal, the reference Gu Zhishu, the peak current reference signal and a pin voltage signal of the third pin CS;
the first pin VS is used for providing a pin voltage for the valley bottom detection module;
the second pin VG is used for realizing the connection between the PWM logic module and the main power switch tube, and a PWM pulse signal is output through the second pin VG;
the third pin CS is used for sampling a voltage signal reflecting the magnitude of the power current;
the fourth pin FB is used for providing a feedback voltage signal.
2. The apparatus of claim 1, wherein the first pin VS is configured to be connected to the converter, the converter comprises an auxiliary winding, a primary winding, and a secondary winding, one end of the auxiliary winding is connected to the first pin VS, and the other end of the auxiliary winding is grounded; one end of the primary winding is connected with an external power supply, and the other end of the primary winding is connected with the first end of the main power switching tube; one end of the secondary winding is connected with one end of the diode, and the other end of the secondary winding is grounded; the other end of the diode is connected with the fourth pin FB through a feedback and isolation module;
the PWM logic module is connected with the second end of the main power switch tube through the second pin VG, and the PWM logic module is connected with the third end of the main power switch tube through the third pin CS and grounded through the sampling resistor.
3. The apparatus of claim 1, wherein the first pin VS is configured to connect to the converter, the converter comprising an auxiliary winding, a primary winding, and a secondary winding;
one end of the auxiliary winding is connected with the first pin VS, and the other end of the auxiliary winding is grounded; one end of the primary winding is connected with an external power supply, and the other end of the primary winding is connected with the MOS integrated system; one end of the secondary winding is connected with one end of the diode, and the other end of the secondary winding is grounded; the other end of the diode is connected with the fourth pin FB through a feedback and isolation module;
the PWM logic module is connected with the MOS integrated system through the second pin VG and the third pin CS, and the MOS integrated system comprises a main power switch tube.
4. The apparatus according to any one of claims 1 to 3,
the valley bottom detection module is used for sampling the pin voltage of the first pin VS, detecting the valley bottom in the working process of the converter, generating a valley bottom signal and transmitting the generated valley bottom signal to the PWM logic module;
the valley bottom number counting module is used for comparing and counting the peak current reference signal with valley adding and valley reducing reference voltages to obtain a reference valley number when the main power switch tube is switched on, and transmitting the reference valley number to the peak current control module and the PWM logic module;
the peak current control module is configured to obtain a peak current reference signal when the main power switch is turned off according to a feedback voltage signal of the fourth pin FB and the reference Gu Zhishu, specifically, after the number of reference valleys is changed, adjust a corresponding relationship between the peak current reference signal and the feedback voltage, where the peak current reference signal decreases by an offset when the number of reference valleys decreases, or the peak current reference signal increases by an offset when the number of reference valleys increases, and transmit the peak current reference signal to the valley bottom number counting module and the PWM logic module;
the PWM logic module is configured to generate a PWM pulse for driving the main power switch tube according to the valley signal, the reference valley number when the main power switch tube is turned on, the peak current reference signal, and the pin voltage signal of the third pin CS, and specifically includes: when the number of the bottom signals is equal to the reference valley value number, the PWM logic module outputs a high level; when the pin voltage signal is greater than the peak current reference signal, the PWM logic module outputs a low level, and a PWM pulse signal is output through the second pin VG.
5. The apparatus of claim 4, wherein the valley number counting module comprises a first selector, a second selector, a first comparator, a second comparator, an exclusive-or gate, and a counter;
the data input end of the first selector is respectively connected with P valley adding reference voltages, the data input end of the second selector is respectively connected with P valley subtracting reference voltages, and P is an integer greater than 1;
the reference valley number is connected to the data selection ends of the first selector and the second selector, the data output ends of the first selector and the second selector are respectively connected to the positive input end of the first comparator and the negative input end of the second comparator, the peak current reference signal is connected to the negative input end of the first comparator and the positive input end of the second comparator, the output end of the first comparator is connected to one input end of the xor gate and the Add end of the counter, the output end of the second comparator is connected to the other input end of the xor gate and the Sub end of the counter, the output end of the xor gate is connected to the enable end of the counter, the clock input end of the counter is connected to the on signal of the main power switch, and the output end of the counter outputs the reference valley number.
6. The apparatus of claim 4, wherein the peak current control module comprises a third selector, a subtractor; the data input end of the third selector is respectively connected with Q reference signals, and Q is an integer greater than 1;
the data selection end of the third selector is connected with the reference Gu Zhishu, the output end of the third selector is connected with the negative input end of the subtracter, and the third selector selects a corresponding reference signal according to the reference valley number and outputs the selected reference signal to the negative input end of the subtracter; the feedback voltage signal is connected with the positive input end of the subtracter and the subtracter outputs the peak current reference signal through a preset proportion link.
7. The apparatus of claim 4, wherein the PWM logic block comprises a digital counter, a digital comparator, an AND gate, a third comparator, an R/S flip-flop, and a one-pulse flip-flop;
the data input end of the digital counter is connected with the valley bottom signal, the reset input end of the digital counter is connected with the switching-on signal of the main power switch tube, the digital counter counts the valley bottom quantity of the current period according to the valley bottom signal, and the digital counter is reset when the main power switch tube is switched on;
the first input end of the digital comparator is connected with the output end of the digital counter;
the second input end of the digital comparator is connected with the reference Gu Zhishu, and the digital comparator outputs high level when the first input end is greater than or equal to the second input end; the first input end of the AND gate is connected with the valley bottom signal, and the second input end of the AND gate is connected with the output end of the digital comparator; the positive input end of the third comparator is connected with the pin voltage signal of the third pin CS, and the negative input end of the third comparator is connected with the peak current reference signal; the set end of the R/S trigger is connected with the output end of the AND gate, and the reset end of the R/S trigger is connected with the output end of the third comparator; the output end of the R/S trigger outputs a driving signal and is connected with the input end of the single pulse trigger, the output end of the single pulse trigger outputs a main power switch tube turn-on signal, when the pin voltage signal of the third pin CS is larger than the peak current reference signal, the third comparator outputs a high level, the R/S trigger is reset, the driving signal is changed into a low level, when the digital comparator outputs a high level and the valley bottom signal is also a high level, the AND gate outputs a high level, the R/S trigger is set, and the driving signal is changed into a high level.
8. The apparatus of claim 4, wherein the pin voltage signal of the third pin CS comprises a voltage signal reflecting the current level of the power loop, and the voltage signal is obtained by sampling the voltage across an external sampling resistor, or is obtained by directly sampling the voltage signal reflecting the current level of the power loop.
9. A valley lock control method for a flyback switching power supply, applied to the apparatus as claimed in any one of claims 1 to 8, the method comprising:
the valley bottom detection module detects valley bottoms in the working process of the converter;
the valley bottom number counting module compares and counts the peak current reference signal with valley adding and valley reducing reference voltages to obtain the reference valley value number when the main power switch tube is switched on, and the valley adding and valley reducing reference voltages enable output power between two adjacent valley bottoms of the converter to be superposed by setting larger hysteresis so as to realize the valley bottom locking function of the converter;
the peak current control module obtains a peak current reference signal when the main power switch tube is turned off according to the feedback voltage and the reference Gu Zhishu, and specifically, after the number of reference valleys is changed, adjusts the corresponding relationship between the peak current reference signal and the feedback voltage, and when the number of reference valleys is reduced, the peak current reference signal is reduced by an offset, or when the number of reference valleys is increased, the peak current reference signal is increased by an offset, so that the output powers of the converter at valley bottom number switching points are approximately equal, and the dynamic performance of the converter is improved;
the PWM logic module is used for generating PWM pulses for driving the main power switch tube according to a valley signal, the reference Gu Zhishu, the peak current reference signal and a pin voltage signal of the third pin CS.
10. A charger, characterized in that it comprises a control device according to any one of claims 1-8.
CN202210995766.2A 2022-08-19 2022-08-19 Valley bottom locking control method of flyback switching power supply and related device Active CN115065253B (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CN202210995766.2A CN115065253B (en) 2022-08-19 2022-08-19 Valley bottom locking control method of flyback switching power supply and related device
CN202211471529.2A CN115940653A (en) 2022-08-19 2022-08-19 Valley bottom locking control method of flyback switching power supply and related charger and device
PCT/CN2022/132278 WO2024036789A1 (en) 2022-08-19 2022-11-16 Valley lockout control method for flyback switch power supply, and related apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210995766.2A CN115065253B (en) 2022-08-19 2022-08-19 Valley bottom locking control method of flyback switching power supply and related device

Related Child Applications (1)

Application Number Title Priority Date Filing Date
CN202211471529.2A Division CN115940653A (en) 2022-08-19 2022-08-19 Valley bottom locking control method of flyback switching power supply and related charger and device

Publications (2)

Publication Number Publication Date
CN115065253A CN115065253A (en) 2022-09-16
CN115065253B true CN115065253B (en) 2022-12-20

Family

ID=83208044

Family Applications (2)

Application Number Title Priority Date Filing Date
CN202210995766.2A Active CN115065253B (en) 2022-08-19 2022-08-19 Valley bottom locking control method of flyback switching power supply and related device
CN202211471529.2A Pending CN115940653A (en) 2022-08-19 2022-08-19 Valley bottom locking control method of flyback switching power supply and related charger and device

Family Applications After (1)

Application Number Title Priority Date Filing Date
CN202211471529.2A Pending CN115940653A (en) 2022-08-19 2022-08-19 Valley bottom locking control method of flyback switching power supply and related charger and device

Country Status (2)

Country Link
CN (2) CN115065253B (en)
WO (1) WO2024036789A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115065253B (en) * 2022-08-19 2022-12-20 深圳英集芯科技股份有限公司 Valley bottom locking control method of flyback switching power supply and related device
CN118713440A (en) * 2024-08-27 2024-09-27 无锡硅动力微电子股份有限公司 Valley bottom locking control circuit

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101188819B1 (en) * 2010-08-26 2012-10-08 주식회사 동부하이텍 average current controller
CN105071662B (en) * 2015-08-26 2018-01-05 矽力杰半导体技术(杭州)有限公司 The switching power source control circuit and control method of a kind of quasi-resonant mode
CN105262333B (en) * 2015-12-02 2017-11-03 成都启臣微电子股份有限公司 A kind of quasi-resonance flyback controller and control method
US10367422B1 (en) * 2018-10-26 2019-07-30 Infineon Technologies Austria Ag Valley mode switching with fixed frequency for switching mode power supply
CN111404361B (en) * 2020-04-29 2024-07-30 杭州必易微电子有限公司 Switch mode power supply circuit, control method thereof and control circuit
CN111490681B (en) * 2020-05-07 2024-07-02 东科半导体(安徽)股份有限公司 Quasi-resonant switching power supply controller based on valley locking
CN112217379B (en) * 2020-09-28 2021-11-23 杭州茂力半导体技术有限公司 Staggered switching power supply and control circuit and control method thereof
CN112332647B (en) * 2020-11-11 2024-07-05 富满微电子集团股份有限公司 Valley locking circuit, chip and power supply based on quasi-resonance control technology
CN114696626B (en) * 2022-04-11 2024-06-25 上海南芯半导体科技股份有限公司 Control circuit of flyback converter
CN115065253B (en) * 2022-08-19 2022-12-20 深圳英集芯科技股份有限公司 Valley bottom locking control method of flyback switching power supply and related device

Also Published As

Publication number Publication date
CN115065253A (en) 2022-09-16
CN115940653A (en) 2023-04-07
WO2024036789A1 (en) 2024-02-22

Similar Documents

Publication Publication Date Title
CN115065253B (en) Valley bottom locking control method of flyback switching power supply and related device
CN115065254B (en) Control device and method of flyback switching power supply and charger
US6157182A (en) DC/DC converter with multiple operating modes
CN111490681B (en) Quasi-resonant switching power supply controller based on valley locking
US7773392B2 (en) Isolated switching power supply apparatus
US8094468B2 (en) Control circuit having off-time modulation to operate power converter at quasi-resonance and in continuous current mode
US7714555B2 (en) Switching regulation device and related method with over-current protection
KR101236955B1 (en) Switching mode power supply and the driving method thereof
TW201935838A (en) Quasi-resonant flyback converter controller
US10958178B2 (en) Control circuit, control method and flyback converter of primary-side feedback control thereof
KR20070076513A (en) Resonant switching power source apparatus
KR20070118751A (en) Qusi-resonat converter and controlling method thereof
TWI671990B (en) Conversion device and control method thereof
KR20090105466A (en) Convertor and the driving method thereof
KR20050025777A (en) Switching power supply apparatus and power supply method thereof
CN111049388B (en) Quasi-resonance control circuit
US10985653B1 (en) Charge pump converter and control method
CN112953242B (en) Instantaneous overpower control method and circuit
US7206208B1 (en) Synchronous rectifying control circuit
US11196351B2 (en) Burst mode operation for a resonant converter
CN220368605U (en) Output protection circuit and switching power supply
JP2020025390A (en) Power converter and control method of the same
US11705909B1 (en) Frequency-locked circuit for variable frequency topology and frequency-locked method thereof
US8564974B2 (en) Switching power source apparatus
CN114567182A (en) Synchronous rectification control device, chip and switching power supply

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant