CN112271939A - Flyback switching power supply circuit for driving LED fluorescent lamp - Google Patents
Flyback switching power supply circuit for driving LED fluorescent lamp Download PDFInfo
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- CN112271939A CN112271939A CN202011229771.XA CN202011229771A CN112271939A CN 112271939 A CN112271939 A CN 112271939A CN 202011229771 A CN202011229771 A CN 202011229771A CN 112271939 A CN112271939 A CN 112271939A
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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
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/02—Conversion of ac power input into dc power output without possibility of reversal
- H02M7/04—Conversion of ac power input into dc power output without possibility of reversal by static converters
- H02M7/12—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/21—Conversion of ac power input into dc power output without possibility of reversal 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
- H02M7/217—Conversion of ac power input into dc power output without possibility of reversal 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
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
- H02H7/125—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for rectifiers
- H02H7/1252—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for rectifiers responsive to overvoltage in input or output, e.g. by load dump
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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
- H02M3/22—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
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/30—Driver circuits
- H05B45/37—Converter circuits
- H05B45/3725—Switched mode power supply [SMPS]
- H05B45/385—Switched mode power supply [SMPS] using flyback topology
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- 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
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
The invention discloses a flyback switching power supply circuit for driving an LED fluorescent lamp, which comprises a mains supply output end, an overcurrent protection module, an EMI filtering module, a primary rectifying module, a power conversion module, a secondary rectifying module, a switching power supply module, an overvoltage protection module, a display circuit and a load circuit which are sequentially connected; the EMI filtering module comprises a filtering capacitor C9 and a piezoresistor ZNR1 which are connected with the mains supply input end in parallel, and a common-mode inductor LF1 which is connected in sequence, the output end of the common-mode inductor is connected with the input end of the primary rectifying module, the overvoltage protection module comprises a transient voltage suppressor which is connected with the output end of the power conversion module in parallel, and a peak eliminating module is connected on the transient voltage suppressor in parallel; the flyback power supply circuit has the advantages of simple circuit, less used components, capability of effectively avoiding the situation of breaking down a switch tube when the leakage inductance of the transformer is generated, and high working reliability compared with the traditional flyback power supply circuit.
Description
Technical Field
The invention relates to the field of switching power supplies, in particular to a flyback switching power supply circuit for driving an LED fluorescent lamp.
Background
The flyback power supply is a circuit which does not provide power output to a load when a primary coil of a transformer is just excited by direct-current pulse voltage, and provides power output to the load only after the excitation voltage of the primary coil of the transformer is switched off; the circuit has the advantages of low cost, simple control, small circuit volume and the like;
however, the transformer of the flyback power supply has a large leakage inductance, and particularly at the moment when the switching tube of the flyback power supply is turned on to be turned off, a large peak current appears on the primary winding side of the transformer, so that the switching tube is broken down, and the household electrical appliances such as an air conditioner and the like cannot normally operate. Therefore, the conventional flyback power supply circuit has the disadvantage of poor operational reliability.
Accordingly, the prior art is deficient and needs improvement.
Disclosure of Invention
The invention provides a flyback switching power supply circuit for driving an LED fluorescent lamp, which solves the problems.
In order to solve the above problems, the technical scheme provided by the invention is as follows:
a flyback switching power supply circuit for driving an LED fluorescent lamp comprises a mains supply output end, an overcurrent protection module, an EMI filtering module, a primary rectifying module, a power conversion module, a secondary rectifying module, a switching power supply module, an overvoltage protection module, a display circuit and a load circuit which are sequentially connected; EMI filtering module includes filter capacitor C9 and piezo-resistor ZNR1 parallelly connected with commercial power input and presses the common mode inductance LF1 of connecting in order, common mode inductance's output is connected with a rectifier module's input, overvoltage protection module includes the parallelly connected transient voltage inhibitor with power conversion module output, parallelly connected peak-eliminating module on the transient voltage inhibitor, the peak-eliminating module carries out the peak-eliminating protection to the transient voltage inhibitor.
In one embodiment, the overcurrent protection module comprises a protection switch F1, a voltage dependent resistor ZNR and a capacitor C9; the utility power output end is connected with connector P1, the first end of protection switch F1 is connected to pin 3 of connector P1, the second end of protection switch F1 is connected with the first end of piezo-resistor ZNR1, the first end of filter capacitor C9 and common mode inductance LF 1's pin 3 respectively, pin 2 of connector P1 is connected with the second end of piezo-resistor ZNR1, the second end of filter capacitor C9 and common mode inductance LF 1's pin 4 respectively, pin 1 ground of connector P1.
In one embodiment, the output end of the common mode inductor LF1 is connected to the input end of the primary rectification module, and the capacitor C8 is connected in parallel with the input end of the primary rectification module, and the larger the capacitance of the capacitor C8 is, the larger the leakage current is.
In one embodiment, the primary rectification module includes diodes D2-D4 and diode D7; the cathode of the diode D2 is connected with the cathode of the diode D3, the anode of the diode D2 is connected with the cathode of the diode D4, the anode of the diode D3 is connected with the cathode of the diode D7 and the second end of the capacitor C8, and the anodes of the diode D4 and the diode D7 are both grounded.
In one embodiment, the secondary rectification module comprises capacitors C4-C7, resistors R1-R2, and a diode D6; the capacitors C4-C6 are connected in parallel, first ends of the capacitors C4-C6 are respectively connected with cathodes of the diodes D2-D3, second ends of the capacitors C4-C6 are grounded, the resistors R1-R3 and the capacitors C7 are connected in parallel, first ends of the resistors R1-R2 and first ends of the capacitors C7 are connected with cathodes of the diodes D2-D3, and second ends of the resistors R1 and second ends of the capacitors C7 are connected with cathodes of the diodes D6.
In one embodiment, the power conversion module includes a transformer L1, a diode D8, and a resistor R6; tap 1 of the transformer L1 is connected with a first end of a capacitor C4-C7 at a first end of a resistor R2 and a first end of a resistor R1, tap 5 of the transformer L1 is connected with the anode of a diode D6, tap 3 of the transformer L1 is grounded, tap 4 of the transformer L1 is connected with the anode of a diode D8, and the cathode of the diode D8 is respectively connected with a second end of the resistor R2 and the first end of the resistor R6.
In one embodiment, the switching power supply module integrated circuit U2 and capacitor C14; pin 3 of the integrated circuit U2 is connected with the second end of the resistor R6 and the second end of the capacitor C14 respectively, pin 2 of the integrated circuit U2 is connected with a tap 5 of the transformer L1, and pin 1 of the integrated circuit U2, the first end of the capacitor C14 and the tap 3 of the transformer L1 are all grounded.
In one embodiment, the overvoltage protection module includes an integrated circuit D5, a capacitor C13, and a resistor R4; pin 3 and pin 1 of the integrated circuit D5 are both connected with a first end of a capacitor C13, a second end of the capacitor C13 is connected with a first end of a resistor R4, and a second end of the resistor R4 is connected with pin 2 of the integrated circuit D5.
In one embodiment, the display circuit is composed of an integrated circuit U1, a resistor R5, resistors R7-R12, a diode D9, an integrated circuit U3 and capacitors C15-16; a first end of the capacitor C16 is connected to pin 4 of the integrated circuit U1, a first end of the resistor R12, and pin 4 of the integrated circuit U2, a second end of the capacitor C14 is connected to pin 1 of the integrated circuit U2, a second end of the resistor R12, and pin 3 of the integrated circuit U1, respectively, pin 1 of the integrated circuit U1 is connected to a second end of the resistor R5, pin 2 of the integrated circuit U1 is connected to a first end of the resistor R9 and pin 3 of the integrated circuit U3, respectively, a second end of the resistor R9 is connected to a first end of the capacitor C15, a second end of the capacitor C15 is connected to a second end of the integrated circuit U3, a second end of the resistor R8, and a first end of the resistor R10, a second end of the resistor R10 is connected to pin 1 of the resistor R10, a first end of the resistor R10 is connected to a first end of the resistor R10, a second end of the resistor R10 is connected to a cathode of the diode R10, and a cathode of the diode 10 is connected to a diode R362 of the resistor, Pin 3 is connected to pin 2 of integrated circuit U3.
In one embodiment, the load circuit includes capacitors C2-C3, an inductor L2, a connector P2, a resistor R3, and capacitors C10-C11; the port 1 of the connector P2 is respectively connected with the cathode of a diode D9, the first end of capacitors C10-C11, the first end of a resistor R3, the second end of capacitors C2-C3 and a tap 9 of a transformer L1, the first ends of the capacitors C2-C3 are all grounded, the second end of the resistor R3 is respectively connected with the second end of a pin 2 capacitor C10, the first end of an inductor L2 and the second end of an electron R4 of an integrated circuit D5, and the second end of the inductor L2 is respectively connected with the second end of a capacitor C11, the first end of a resistor R5, the first end of resistors R7-R8 and the port 2 of the connector P2.
Compared with the prior art, the flyback power supply circuit has the advantages that by adopting the scheme, the EMI filtering module is used for increasing the filtering function of commercial power, meanwhile, the voltage-sensitive diode is used for effectively protecting circuit components, when in use, the capacitor C8 is used for placing leakage current, and meanwhile, the overvoltage protection module is arranged for eliminating the peak of the current, so that the breakdown of the switch power supply module is avoided.
Drawings
For a clearer explanation of the embodiments or technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the invention, and it is obvious for a person skilled in the art that other drawings can be obtained from the drawings without creative efforts.
FIG. 1 is a schematic block diagram of the present invention;
FIG. 2 is a circuit diagram of the overall structure of the present invention;
FIG. 3 is a block diagram of the overall architecture of the present invention;
as shown in the above legend: a commercial power output end 1; an overcurrent protection module 2; an EMI filtering module 3; a primary rectification module 4; a power conversion module 5; a secondary rectification module 6; a switching power supply module 7; an overvoltage protection module 8; a display circuit 9; a load circuit 10.
Detailed Description
In order to facilitate an understanding of the invention, the invention is described in more detail below with reference to the accompanying drawings and specific examples. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The use of the terms "fixed," "integrally formed," "left," "right," and the like in this specification is for illustrative purposes only, and elements having similar structures are designated by the same reference numerals in the figures.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
As shown in fig. 1-3, one embodiment of the present invention is:
a flyback switching power supply circuit for driving an LED fluorescent lamp comprises a mains supply output end, an overcurrent protection module, an EMI filtering module, a primary rectifying module, a power conversion module, a secondary rectifying module, a switching power supply module, an overvoltage protection module, a display circuit and a load circuit which are sequentially connected; EMI filtering module includes filter capacitor C9 and piezo-resistor ZNR1 parallelly connected with commercial power input and presses the common mode inductance LF1 of connecting in order, common mode inductance's output is connected with a rectifier module's input, overvoltage protection module includes the parallelly connected transient voltage inhibitor with power conversion module output, parallelly connected peak-eliminating module on the transient voltage inhibitor, the peak-eliminating module carries out the peak-eliminating protection to the transient voltage inhibitor.
In a preferred technical scheme, the overcurrent protection module comprises a protection switch F1, a voltage dependent resistor ZNR and a capacitor C9; the utility power output end is connected with connector P1, the first end of protection switch F1 is connected to pin 3 of connector P1, the second end of protection switch F1 is connected with the first end of piezo-resistor ZNR1, the first end of filter capacitor C9 and common mode inductance LF 1's pin 3 respectively, pin 2 of connector P1 is connected with the second end of piezo-resistor ZNR1, the second end of filter capacitor C9 and common mode inductance LF 1's pin 4 respectively, pin 1 ground of connector P1.
According to the preferable technical scheme, the output end of the common-mode inductor LF1 is connected with the input end of the primary rectification module, the capacitor C8 is connected with the input end of the primary rectification module in parallel, and the larger the capacitance of the capacitor C8 is, the larger the leakage current is.
In a preferred technical scheme, the primary rectifying module comprises diodes D2-D4 and a diode D7; the cathode of the diode D2 is connected with the cathode of the diode D3, the anode of the diode D2 is connected with the cathode of the diode D4, the anode of the diode D3 is connected with the cathode of the diode D7 and the second end of the capacitor C8, and the anodes of the diode D4 and the diode D7 are both grounded.
In a preferred technical scheme, the secondary rectification module comprises capacitors C4-C7, resistors R1-R2 and a diode D6; the capacitors C4-C6 are connected in parallel, first ends of the capacitors C4-C6 are respectively connected with cathodes of the diodes D2-D3, second ends of the capacitors C4-C6 are grounded, the resistors R1-R3 and the capacitors C7 are connected in parallel, first ends of the resistors R1-R2 and first ends of the capacitors C7 are connected with cathodes of the diodes D2-D3, and second ends of the resistors R1 and second ends of the capacitors C7 are connected with cathodes of the diodes D6.
In a preferred embodiment, the power conversion module includes a transformer L1, a diode D8, and a resistor R6; tap 1 of the transformer L1 is connected with a first end of a capacitor C4-C7 at a first end of a resistor R2 and a first end of a resistor R1, tap 5 of the transformer L1 is connected with the anode of a diode D6, tap 3 of the transformer L1 is grounded, tap 4 of the transformer L1 is connected with the anode of a diode D8, and the cathode of the diode D8 is respectively connected with a second end of the resistor R2 and the first end of the resistor R6.
In a preferred technical solution, the switching power supply module integrated circuit U2 and the capacitor C14; pin 3 of the integrated circuit U2 is connected with the second end of the resistor R6 and the second end of the capacitor C14 respectively, pin 2 of the integrated circuit U2 is connected with a tap 5 of the transformer L1, and pin 1 of the integrated circuit U2, the first end of the capacitor C14 and the tap 3 of the transformer L1 are all grounded.
In a preferred technical scheme, the overvoltage protection module comprises an integrated circuit D5, a capacitor C13 and a resistor R4; pin 3 and pin 1 of the integrated circuit D5 are both connected with a first end of a capacitor C13, a second end of the capacitor C13 is connected with a first end of a resistor R4, and a second end of the resistor R4 is connected with pin 2 of the integrated circuit D5.
In a preferable technical scheme, the display circuit comprises an integrated circuit U1, a resistor R5, resistors R7-R12, a diode D9, an integrated circuit U3 and capacitors C15-16; a first end of the capacitor C16 is connected to pin 4 of the integrated circuit U1, a first end of the resistor R12, and pin 4 of the integrated circuit U2, a second end of the capacitor C14 is connected to pin 1 of the integrated circuit U2, a second end of the resistor R12, and pin 3 of the integrated circuit U1, respectively, pin 1 of the integrated circuit U1 is connected to a second end of the resistor R5, pin 2 of the integrated circuit U1 is connected to a first end of the resistor R9 and pin 3 of the integrated circuit U3, respectively, a second end of the resistor R9 is connected to a first end of the capacitor C15, a second end of the capacitor C15 is connected to a second end of the integrated circuit U3, a second end of the resistor R8, and a first end of the resistor R10, a second end of the resistor R10 is connected to pin 1 of the resistor R10, a first end of the resistor R10 is connected to a first end of the resistor R10, a second end of the resistor R10 is connected to a cathode of the diode R10, and a cathode of the diode 10 is connected to a diode R362 of the resistor, Pin 3 is connected to pin 2 of integrated circuit U3.
In a preferred technical scheme, the load circuit comprises capacitors C2-C3, an inductor L2, a connector P2, a resistor R3 and capacitors C10-C11; the port 1 of the connector P2 is respectively connected with the cathode of a diode D9, the first end of capacitors C10-C11, the first end of a resistor R3, the second end of capacitors C2-C3 and a tap 9 of a transformer L1, the first ends of the capacitors C2-C3 are all grounded, the second end of the resistor R3 is respectively connected with the second end of a pin 2 capacitor C10, the first end of an inductor L2 and the second end of an electron R4 of an integrated circuit D5, and the second end of the inductor L2 is respectively connected with the second end of a capacitor C11, the first end of a resistor R5, the first end of resistors R7-R8 and the port 2 of the connector P2.
The working principle is as follows:
the mains supply is connected into the connector P1, the connector P1 provides electric energy, and the piezoresistor ZNR1 can prevent surge and lightning stroke to protect the circuit when receiving large current impact; the higher the temperature of the piezoresistor ZNR1 is, the smaller the resistance value thereof is, the larger current can be filtered by the capacitor C9, then the current passes through the common-mode inductor LF1 and is radiated by the common-mode inductor LF1, when the current passes through the capacitor C8, the larger the capacitance of the capacitor C8 is, the larger the leakage current is, the current is output after passing through the primary rectifying module, the output current is unstable direct current, at this time, the integrated circuit U2 is conducted, the direct current passes through the transformer L1 and is rectified again by the secondary rectifying module, the current after the secondary rectification is limited by the switch resistor R2, the initial current is small, the current passes through the resistor R6 and charges the capacitor C14, the capacitor C14 energizes the integrated circuit U2, then the integrated circuit U2 is closed, the current is output by the secondary winding of the transformer L1, and the voltage output by the secondary winding is larger, the peak value is too high, after the peak eliminating treatment is carried out on the output voltage by the overvoltage protection module, stable direct current is formed to enable the direct current to enter the load circuit and the display circuit, components on the load circuit are driven by the stable direct current, meanwhile, a display lamp on the display circuit detects the current which is left through, when the current is too large, the light emitting diode is brighter, when the current is smaller, the light emitting diode is darkened, and meanwhile, the stability of the current of the positive load circuit and the negative load circuit is regulated and controlled through U2 in an integrated store.
Compared with the prior art, the flyback power supply circuit has the advantages that by adopting the scheme, the EMI filtering module is used for increasing the filtering function of commercial power, meanwhile, the voltage-sensitive diode is used for effectively protecting circuit components, when in use, the capacitor C8 is used for placing leakage current, and meanwhile, the overvoltage protection module is arranged for eliminating the peak of the current, so that the breakdown of the switch power supply module is avoided.
The technical features mentioned above are combined with each other to form various embodiments which are not listed above, and all of them are regarded as the scope of the present invention described in the specification; also, modifications and variations may be suggested to those skilled in the art in light of the above teachings, and it is intended to cover all such modifications and variations as fall within the true spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. A flyback switching power supply circuit for driving an LED fluorescent lamp comprises a mains supply output end, an overcurrent protection module, an EMI filtering module, a primary rectifying module, a power conversion module, a secondary rectifying module, a switching power supply module, an overvoltage protection module, a display circuit and a load circuit which are sequentially connected; the overvoltage protection device is characterized in that the EMI filtering module comprises a filtering capacitor C9 and a piezoresistor ZNR1 which are connected with a mains supply input end in parallel and a common-mode inductor LF1 which is connected in sequence, the output end of the common-mode inductor is connected with the input end of a primary rectifying module, the overvoltage protection module comprises a transient voltage suppressor which is connected with the output end of a power conversion module in parallel, a peak eliminating module is connected on the transient voltage suppressor in parallel, and the peak eliminating module carries out peak eliminating protection on the transient voltage suppressor.
2. The flyback switching power supply circuit of claim 1, wherein the over-current protection module comprises a protection switch F1, a voltage dependent resistor ZNR and a capacitor C9; the utility power output end is connected with connector P1, the first end of protection switch F1 is connected to pin 3 of connector P1, the second end of protection switch F1 is connected with the first end of piezo-resistor ZNR1, the first end of filter capacitor C9 and common mode inductance LF 1's pin 3 respectively, pin 2 of connector P1 is connected with the second end of piezo-resistor ZNR1, the second end of filter capacitor C9 and common mode inductance LF 1's pin 4 respectively, pin 1 ground of connector P1.
3. The flyback switching power supply circuit of claim 1, wherein the output terminal of the common mode inductor LF1 is connected to the input terminal of the primary rectifying module, and the input terminal of the capacitor C8 is connected in parallel with the input terminal of the primary rectifying module, and the larger the capacitance of the capacitor C8 is, the larger the leakage current is.
4. The flyback switching power supply circuit of claim 3, wherein the primary rectification module comprises diodes D2-D4 and D7; the cathode of the diode D2 is connected with the cathode of the diode D3, the anode of the diode D2 is connected with the cathode of the diode D4, the anode of the diode D3 is connected with the cathode of the diode D7 and the second end of the capacitor C8, and the anodes of the diode D4 and the diode D7 are both grounded.
5. The flyback switching power supply circuit of claim 1, wherein the secondary rectification module comprises capacitors C4-C7, resistors R1-R2, and a diode D6; the capacitors C4-C6 are connected in parallel, first ends of the capacitors C4-C6 are respectively connected with cathodes of the diodes D2-D3, second ends of the capacitors C4-C6 are grounded, the resistors R1-R3 and the capacitors C7 are connected in parallel, first ends of the resistors R1-R2 and first ends of the capacitors C7 are connected with cathodes of the diodes D2-D3, and second ends of the resistors R1 and second ends of the capacitors C7 are connected with cathodes of the diodes D6.
6. The flyback switching power supply circuit of claim 5, wherein the power conversion module comprises a transformer L1, a diode D8, and a resistor R6; tap 1 of the transformer L1 is connected with a first end of a capacitor C4-C7 at a first end of a resistor R2 and a first end of a resistor R1, tap 5 of the transformer L1 is connected with the anode of a diode D6, tap 3 of the transformer L1 is grounded, tap 4 of the transformer L1 is connected with the anode of a diode D8, and the cathode of the diode D8 is respectively connected with a second end of the resistor R2 and the first end of the resistor R6.
7. The flyback switching power supply circuit of claim 6, wherein the switching power supply module integrated circuit is U2 and a capacitor C14; pin 3 of the integrated circuit U2 is connected with the second end of the resistor R6 and the second end of the capacitor C14 respectively, pin 2 of the integrated circuit U2 is connected with a tap 5 of the transformer L1, and pin 1 of the integrated circuit U2, the first end of the capacitor C14 and the tap 3 of the transformer L1 are all grounded.
8. The flyback switching power supply circuit of claim 1, wherein the overvoltage protection module comprises an integrated circuit D5, a capacitor C13, and a resistor R4; pin 3 and pin 1 of the integrated circuit D5 are both connected with a first end of a capacitor C13, a second end of the capacitor C13 is connected with a first end of a resistor R4, and a second end of the resistor R4 is connected with pin 2 of the integrated circuit D5.
9. The flyback switching power supply circuit of claim 8, wherein the display circuit is integrated with U1, R5, R7-R12, diode D9, integrated circuit U3, and C15-16; a first end of the capacitor C16 is connected to pin 4 of the integrated circuit U1, a first end of the resistor R12, and pin 4 of the integrated circuit U2, a second end of the capacitor C14 is connected to pin 1 of the integrated circuit U2, a second end of the resistor R12, and pin 3 of the integrated circuit U1, respectively, pin 1 of the integrated circuit U1 is connected to a second end of the resistor R5, pin 2 of the integrated circuit U1 is connected to a first end of the resistor R9 and pin 3 of the integrated circuit U3, respectively, a second end of the resistor R9 is connected to a first end of the capacitor C15, a second end of the capacitor C15 is connected to a second end of the integrated circuit U3, a second end of the resistor R8, and a first end of the resistor R10, a second end of the resistor R10 is connected to pin 1 of the resistor R10, a first end of the resistor R10 is connected to a first end of the resistor R10, a second end of the resistor R10 is connected to a cathode of the diode R10, and a cathode of the diode 10 is connected to a diode R362 of the resistor, Pin 3 is connected to pin 2 of integrated circuit U3.
10. The flyback switching power supply circuit of claim 9, wherein the load circuit comprises capacitors C2-C3, an inductor L2, a connector P2, a resistor R3 and capacitors C10-C11; the port 1 of the connector P2 is respectively connected with the cathode of a diode D9, the first end of capacitors C10-C11, the first end of a resistor R3, the second end of capacitors C2-C3 and a tap 9 of a transformer L1, the first ends of the capacitors C2-C3 are all grounded, the second end of the resistor R3 is respectively connected with the second end of a pin 2 capacitor C10, the first end of an inductor L2 and the second end of an electron R4 of an integrated circuit D5, and the second end of the inductor L2 is respectively connected with the second end of a capacitor C11, the first end of a resistor R5, the first end of resistors R7-R8 and the port 2 of the connector P2.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011229771.XA CN112271939A (en) | 2020-11-06 | 2020-11-06 | Flyback switching power supply circuit for driving LED fluorescent lamp |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011229771.XA CN112271939A (en) | 2020-11-06 | 2020-11-06 | Flyback switching power supply circuit for driving LED fluorescent lamp |
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| CN112271939A true CN112271939A (en) | 2021-01-26 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202011229771.XA Pending CN112271939A (en) | 2020-11-06 | 2020-11-06 | Flyback switching power supply circuit for driving LED fluorescent lamp |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115294929A (en) * | 2022-10-10 | 2022-11-04 | 深圳中电数码显示有限公司 | Control method and control device of LED screen |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203167379U (en) * | 2013-04-03 | 2013-08-28 | 深圳斯派克节能服务有限公司 | An isolated driving power supply of a LED fluorescent lamp |
| CN204517680U (en) * | 2015-04-01 | 2015-07-29 | 西安科技大学 | A kind of interchange inputs doubleway output DC-stabilized circuit |
| CN110972365A (en) * | 2019-12-19 | 2020-04-07 | 深圳市高众科技工程有限公司 | Silicon controlled rectifier circuit based on high-efficiency off-line LED dimming |
| CN211377890U (en) * | 2020-03-04 | 2020-08-28 | 张元茂 | 40W flyback power supply circuit |
-
2020
- 2020-11-06 CN CN202011229771.XA patent/CN112271939A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203167379U (en) * | 2013-04-03 | 2013-08-28 | 深圳斯派克节能服务有限公司 | An isolated driving power supply of a LED fluorescent lamp |
| CN204517680U (en) * | 2015-04-01 | 2015-07-29 | 西安科技大学 | A kind of interchange inputs doubleway output DC-stabilized circuit |
| CN110972365A (en) * | 2019-12-19 | 2020-04-07 | 深圳市高众科技工程有限公司 | Silicon controlled rectifier circuit based on high-efficiency off-line LED dimming |
| CN211377890U (en) * | 2020-03-04 | 2020-08-28 | 张元茂 | 40W flyback power supply circuit |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115294929A (en) * | 2022-10-10 | 2022-11-04 | 深圳中电数码显示有限公司 | Control method and control device of LED screen |
| CN115294929B (en) * | 2022-10-10 | 2022-12-27 | 深圳中电数码显示有限公司 | Control method and control device of LED screen |
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