CN201608638U - Fly-back power supply overpower compensation device inputted by wide voltage - Google Patents

Fly-back power supply overpower compensation device inputted by wide voltage Download PDF

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CN201608638U
CN201608638U CN2010201243525U CN201020124352U CN201608638U CN 201608638 U CN201608638 U CN 201608638U CN 2010201243525 U CN2010201243525 U CN 2010201243525U CN 201020124352 U CN201020124352 U CN 201020124352U CN 201608638 U CN201608638 U CN 201608638U
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power supply
overpower
opp
fly
primary side
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余祚尚
李宗晏
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TPV Electronics Fujian Co Ltd
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TPV Electronics Fujian Co Ltd
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    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10Technologies 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

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Abstract

The utility model relates to a fly-back power supply overpower compensation device inputted by wide voltage, which comprises a fly-back transformer of a fly-back power supply, an OPP overpower compensation circuit and a fly-back power supply PWM control IC. The compensation device is characterized in that a winding is additionally arranged on a primary side of the transformer; one end of the winding serving as an unlike end is connected with a reference ground of the primary side of the fly-back transformer; and the other end of the winding serving as a same end transmits coupled voltage to an OPP overpower protection and detection function end CS of the fly-back power supply PWM control IC through the OPP overpower compensation circuit to serve as OPP overpower compensation. The compensation device enables wide power supply (input ranging from 90Vrms to 264Vrms alternating current) overpower protection points to be closer, the OPP overpower compensation circuit does not work when in light load, namely, when outputting the light load, the OPP overpower compensation circuit avoids loss of energy, and the fly-back power supply overpower compensation device can be applied to fly-back wide power supply with extremely low requirements on standby power consumption, is convenient and safe in use, and simultaneously can reduce the problem of damage of parts such as a switch MOS pipe and the like due to overload or short output.

Description

The flyback power supply Overpower compensating device of wide voltage input
Technical field
The utility model relates to a kind of flyback power supply Overpower compensating device of wide voltage input, because compensation circuit is turned off during underloading, not power consumption itself is so can be applicable in the middle of the low-down liquid crystal display product flyback power supply of standby power requirement.
Background technology
Present most of liquid crystal display product power supply adopts the reverse exciting topological framework usually; and input voltage adopts 90Vrms-264Vrms wide power mode to design usually; during in order to ensure output overloading or short circuit; the power supply part is not damaged or does not produce safety and draws the trouble problem; usually can design overpower protection (OPP) function on the power panel, and present most of flyback power supply overpower protection is just like two kinds of Fig. 1 and Fig. 3.
Fig. 1 overpower protection loop is by Rs, R901, C901 forms, whether the current maxima that flows through by detecting Rs resistance has the inner OPP overpower protection of the PWMIC of reaching point to determine whether turning off PWMIC output, this overpower protection circuit is a kind of circuit that does not adopt any high-low pressure Overpower compensating, is input as between the 90Vrms-264Vrms at power supply, and the big capacitor C 903 voltage Vc903 voltage differences of power frequency filtering are very big, as: during the 90Vrms input voltage, Vc903 voltage is about 120V; And during 264Vrms during input voltage, Vc903 voltage is about 370V, because output overpower protection point Popp is big or small relevant with Vc903*u* (Ip1+Ip2)/2 relational expression; (the Maximum Power Output when Popp represents output overloading; Vc903 represents big capacitor C 903 average voltages of power frequency filtering, and is relevant with the input ac voltage size; As shown in Figure 2, when Ip1 represents that the Q901MOS switching tube is opened, flow through the electric current of Rs resistance, Ip2 represents that the Q901MOS pipe turn-offs the electric current that flows through Rs resistance before; U represents T901 transformer conversion efficiency ), Wherein: Vc903=Lp* (Ip2-Ip1)/Ton(Lp indication transformer primary side Np1 winding sensibility reciprocal, Ton represents Q901MOS switching tube ON time) Ip2=Vrs/Rs(Vrs represents the voltage that detects on the Rs resistance; Rs represents the Rs resistance value), 0 ≦ Ip1<Ip2, when Ip1=0, transformer work enters the discontinuous mode operating state; When 0<Ip1<Ip2; transformer work continuous mode operating state; and when Vrs=Ip2*Rs carried out through R901 resistance and C901 electric capacity that resultant voltage is greater than PWMICCS end internal protection magnitude of voltage after the low-pass filtering, PWMIC inside just began to do the action of OPP overpower protection.From top relational expression and explanation as can be known: flyback power supply OPP overpower protection point size and input voltage be voltage Vc903 on difference that 90Vrsm-264Vrms time protection is put and the big electric capacity of C903 power frequency filtering; the sensibility reciprocal of transformer T901 primary side Np1 winding and the isallobaric device parameter of transformer transformation efficiency; Rs current sense resistance; R901 resistance is relevant with the RC low-pass filter circuit that C901 electric capacity is formed; if these parameter designing are reasonable inadequately; OPP will occur and cross the defeated rate protection point set point that departs from objectives; at present in the middle of these parameters; Vc903 has the greatest impact at wide voltage source on the big capacitor C 903 of power frequency filtering; 370V/120V=3.08 when Vc903 is input 90Vrms during power input voltage 264Vrms; promptly 3.08 times; therefore overpower protection point greatly in the time of usually can be than input 90Vrms when importing 264Vrms; as: the design of overpower protection point is at 40W during input 90Vrms; then the overpower protection point becomes 60W when 264Vrms; when therefore design does not have the flyback power supply electricity of OPP compensation; to enough design margins to be arranged to its inverse-excitation type transformer and MOS switching tube; when output overloading or short circuit; also not reaching full at transformer closes and before switch MOS pipe Q901Ids drain electrode end electric current also do not reach the specification maximum; PWMIC must begin to do OPP protection action; draw trouble to guarantee that the power supply part is not damaged or does not produce safety; and design margin increases and may increase by design cost; and because input 90Vrsm differs greatly to 264VrmsOPP overpower protection point; therefore also increase the power supply design difficulty, also caused parts such as causing switch MOS pipe Q901 because of output short-circuit or overload to occur damaging simultaneously easily.
Fig. 2 overpower protection loop is by Rs, R901, C901, R912 forms, wherein R912 is connected between big electric capacity anode of C903 power frequency filtering and the IC901OPP overpower protection measuring ability end (CS end), as wide power high-low pressure OPP Overpower compensating circuit, is that big capacitor C 903 voltages of power frequency are about 120V in the 90Vrms at input voltage, IC901OPP overpower protection measuring ability end this moment (CS end) obtains less OPP Overpower compensating, offset current I=120V/ (R905+R901+Rs); At input voltage is that big capacitor C 903 voltages of power frequency are about 370V in the 264Vrms, and IC901 OPP overpower protection measuring ability end this moment (CS end) obtains bigger OPP Overpower compensating, offset current I=370V/ (R905+R901+Rs); Many more by the high more resultant OPP Overpower compensating of power supply input ac voltage, make that to be input as between the 90Vrms-264Vrms OPP overpower protection point more approaching, because compensating resistance R912 is connected on power frequency capacitor C 903 anodes and IC901CS low-pressure end, as input voltage 264Vrms, direct voltage is about 370V on the power frequency electric capacity, then the ohmically power consumption P=370V*370V/R912 of R912 this moment; Adopt this kind overpower to mend to taste device, when R912 resistance during less than 1M, excessive OPP Overpower compensating can appear in circuit; It is better that the R905 value is set in 1M left and right sides OPP Overpower compensating effect, but loss this moment power consumption on R912 resistance is bigger, is about 0.136mW, can't use on the lower liquid crystal display product of stand-by power consumption.The R912 resistance value the not enough problem of OPP Overpower compensating occurs greater than more than the 2M, and when promptly power supply was imported between 90Vrms-264Vrms, power supply output overpower protection point began to occur bigger difference.
Summary of the invention
In order to overcome the deficiency of above-mentioned technology, the utility model improves existing flyback power supply Overpower compensating circuit, a kind of device of flyback power supply Overpower compensating of wide voltage input is provided, it adopts following scheme to realize: the inverse-excitation type transformer T901 that comprises flyback power supply, OPP Overpower compensating circuit, and as flyback power supply PWM control IC, it is characterized in that: described inverse-excitation type transformer T901 comprises:
One primary side Np1 winding, its end p11 of the same name is connected with the big capacitance cathode end of C903 power frequency, and different name end p12 is connected with the drain electrode of MOS switching tube Q901;
One primary side Np2 winding, its end of the same name is connected with reference to ground with inverse-excitation type transformer T901 primary side, and the different name end is connected with the Vcc power supply circuits;
One primary side NP3 winding, its different name end p32 connect inverse-excitation type transformer T901 primary side with reference to ground, and the other end is connected with OPP Overpower compensating circuit as end p31 of the same name;
Primary side Ns1, Ns2 ... the Nsn winding, its termination inverse-excitation type transformer T901 primary side of the same name is with reference to ground, and the different name end is connected with output rectification circuit;
Described OPP Overpower compensating circuit output end be connected as flyback power supply PWM control IC, described pulse-width modulation output function end Gate as flyback power supply PWM control IC is connected with the grid of MOS switching tube Q901.
Described OPP Overpower compensating circuit is provided with the switching tube that a group transistor Q902, Q903 do OPP Overpower compensating circuit.
The utility model is skillfully constructed, circuit structure is simple, by increasing this OPP Overpower compensating circuit, make power supply product more meet the requirement of wide power product design specification (PDS), make product safer in use, simultaneously also can reduce or cause the problem of damage parts such as MOS switching tube in short-term, effectively prolong product useful life because of output overloading.
Description of drawings
Fig. 1 is that known input 90Vrms-264Vrms inverse-excitation type wide power does not adopt any OPP Overpower compensating circuit to have the flyback power supply in overpower protection loop.
Fig. 2 is that current waveform figure under the state is thought in flyback power supply Q901MOS management.
Fig. 3 is that known input 90Vrms-264Vrms inverse-excitation type wide power uses a power resistor R912 to be connected to the schematic diagram that the big electric capacity anode of C903 power frequency filtering and PWMICOPP overpower protection measuring ability end (CS end) are done the OPP Overpower compensating.
Fig. 4 is the circuit structure principle schematic of the utility model embodiment.
Fig. 5 is the circuit theory schematic diagram that the utility model embodiment PWMIC detects the output voltage feedback end.
Embodiment
It is as shown in Figure 4 a kind of that present embodiment provides, this enforcement provides a kind of device of flyback power supply Overpower compensating of wide voltage input, the inverse-excitation type transformer T901 that comprises flyback power supply, OPP Overpower compensating circuit, and as flyback power supply PWM control IC, it is characterized in that: described inverse-excitation type transformer T901 comprises:
One primary side Np1 winding, its end p11 of the same name is connected with the big capacitance cathode end of C903 power frequency, and different name end p12 is connected with the drain electrode of MOS switching tube Q901;
One primary side Np2 winding, its end of the same name is connected with reference to ground with inverse-excitation type transformer T901 primary side, and the different name end is connected with the Vcc power supply circuits;
One primary side NP3 winding, its different name end p32 connect inverse-excitation type transformer T901 primary side with reference to ground, and the other end is connected with OPP Overpower compensating circuit as end p31 of the same name;
Primary side Ns1, Ns2 ... the Nsn winding, its termination inverse-excitation type transformer T901 primary side of the same name is with reference to ground, and the different name end is connected with output rectification circuit;
Described OPP Overpower compensating circuit output end be connected as flyback power supply PWM control IC, described pulse-width modulation output function end Gate as flyback power supply PWM control IC is connected with the grid of MOS switching tube Q901.In present embodiment, the number of turns of described winding is a circle.
Describedly comprise pulse-width modulation output function end Gate at least as flyback power supply PWM control IC, PWMIC function of supplying power end Vcc, OPP output overpower protection measuring ability CS, PWMIC detects output voltage feedback end FB, and PWMIC connects with reference to ground end GND.The inner that described PWMIC detects output voltage feedback end FB is connected with a pull-up resistor Rfb one end, and another termination of pull-up resistor Rfb one reference voltage V ref; When the voltage of OPP output overpower protection measuring ability end CS detects the voltage of output voltage feedback end FB greater than PWMIC, pulse-width modulation output function end Gate output low level; Described PWMIC detects output voltage feedback end FB voltage and a flyback power supply output band year pass is: when being output as underloading, PWMIC detects output voltage feedback end FB voltage and reduces to lower voltage quasi position, and the OPP of PWMIC output overpower protection measuring ability end CS detects less voltage, and this moment, the pulse-width modulation output function end Gate of PWMIC exported less pulse width modulation duty; And when output year change is heavy, PWMIC detects output voltage feedback end FB voltage and rises to the higher voltage position, this moment, the pulse-width modulation output function end Gate output pulse width modulation duty cycle of PWMIC increased, and the OPP of PWMIC output overpower protection measuring ability end CS detects bigger voltage; When output overloading; PWMIC detects output voltage feedback end FB voltage and rises to higher voltage; this moment, the pulse-width modulation output function end Gate output pulse width modulation duty cycle of PWMIC continued to increase; and the OPP of PWMIC output overpower protection measuring ability end CS detects voltage when reaching the OPP protection point reference voltage of PWMIC inner setting, and PWMIC just begins to do the OPP overpower protection.
What deserves to be mentioned is, for device of the present utility model can well be applied in the middle of the power supply of the very low liquid crystal display product of standby power requirement.Described OPP Overpower compensating circuit inside is provided with the switching tube that a group transistor (Q902, Q903) is done OPP Overpower compensating circuit, determine whether to do OPP Overpower compensating circuit by detecting PWMICFB terminal voltage size and open or turn-off, when power supply is output as underloading, OPP Overpower compensating circuit is turned off by this transistor (Q902, Q903), and the Overpower compensating circuit stops the OPP overpower protection measuring ability end CS of PWMIC is done wide power interchange input high-low pressure Overpower compensating; When power supply was output as heavy duty, OPP Overpower compensating circuit was opened by transistor (Q902, Q903), and OPP Overpower compensating circuit begins the OPP overpower protection measuring ability end CS of PWMIC is done wide power interchange input high-low pressure Overpower compensating.
In order to allow those skilled in the art can clearly understand the utility model, some control principles of present embodiment circuit are carried out concrete introduction below in conjunction with Fig. 4:
It is as follows how to allow the OPP compensating circuit open the operation principle of still turn-offing when one, flyback power supply is exported weight:
When power supply output with load when reducing, electric power output voltage Vout increases, because of V1=Vout*R904/ (R903+R904), so V1 voltage increases, because of V1 is the R end that is input to TL431, and the R end is the anode of TL431 internal error amplifier, so TL431 internal transistor base current Ib1 increases, because of If=Ib1*K (K is a TL431 internal transistor multiplication factor), so flowing through IC902 optocoupler internal illumination diode electric current I f increases, because of IC902 optocoupler Ic1=If*CTR (CTR is that the inner photoelectricity of optocoupler transforms transmission ratio), so, IC902 optocoupler output current Ic1 increases, because of optocoupler output (C end) is connected with the FB end of IC901PWMIC, with reference to figure 5-the inner FB end of IC901PWMIC is connected with a pull-up resistor Rfb one end, and another termination one reference voltage of pull-up resistor Rfb, its Vfb=Vref-Ic1*Rfb, so PWMICFB terminal voltage Vfb reduces, because of Vg=Vfb*R909/ (R909+R910), so Q902 switching tube grid Vg voltage reduces, when power supply output is carried when light more, Q902 switching tube grid voltage Vg is just more little, and when Vg voltage during less than Q902 switching tube threshold voltage Vgs (th), the Q902 switching tube turn-offs, this moment, the Q903 switching tube also was turned off, and promptly OPP Overpower compensating circuit quits work.When power supply output with load when increasing, electric power output voltage Vout reduces, because of V1=Vout*R904/ (R903+R904), so V1 voltage reduces, because of V1 is the R end that is input to TL431, and the R end is the anode of TL431 internal error amplifier, so TL431 internal transistor base current Ib1 reduces, because of If=Ib1*K (K is a TL431 internal transistor multiplication factor), so flowing through IC902 optocoupler internal illumination diode electric current I f reduces, because of IC902 optocoupler Ic1=If*CTR (CTR is that the inner photoelectricity of optocoupler transforms transmission ratio), so, IC902 optocoupler output current Ic1 reduces, because of optocoupler output (C end) is connected with the FB end of IC901PWMIC, with reference to figure 5-the inner FB end of IC901PWMIC is connected with a pull-up resistor Rfb one end, and another termination one reference voltage of pull-up resistor Rfb, its Vfb=Vref-Ic1*Rfb, so PWMICFB terminal voltage Vfb increases, because of Vg=Vfb*R909/ (R909+R910), so Q902 switching tube grid Vg voltage increases, when power supply output is carried when heavy more, Q902 switching tube grid voltage Vg is just big more, and when Vg voltage during greater than Q902 switching tube threshold voltage Vgs (th), the Q902 switching tube is opened, this moment, the Q903 switching tube also was opened, and promptly OPP Overpower compensating circuit is started working.
Two, OPP Overpower compensating operation principle:
Because inverse-excitation type wide power OPP overpower protection point is common: when input 90Vrms alternating voltage, OPP protection point is less, when input 264Vrms alternating voltage, OPP protection point is bigger, therefore wish when being input as 90Vrms, obtain less OPP compensation, and when being input as 264Vrms, obtain big OPP compensation, compensate when big more, output overpower protection point can become low more, therefore can make that the OPP overpower protection point of power input voltage between 90Vrms-264Vrms is more approaching by R906/R901 resistance size in the adjustment OPP compensating circuit, concrete operation principle is as follows: it is 1 circle Np3 winding that transformer T901 is increased by a number of turns, and Np1 winding p11 end is end of the same name with Np3 winding p31 end; And Np1 winding p12 end holds relative p11/p31 end to be the different name end with Np3 winding p32, that is: when MOS switching tube Q901 drain electrode end is opened, T901 transformer Np1 winding p11 end is for just, and the p12 end is to bear; Np3 winding p31 end is for just, and the p32 end is for bearing.This moment, the Np3 winding Np1 winding that is coupled was represented the number of turns of Np3 winding to voltage Vnp3=Vc903*Np3/Np1=Vc903/Np1(Np3; Np1 represents the number of turns of Np1 winding; Vc903 represents the direct voltage on the big capacitor C 903 of power frequency), Np3 voltage that winding is coupled to transfers OPP Overpower compensating circuit and does the OPP Overpower compensating through R911 à D901 à Q903 à R906 to the PWMICCS end, when power input voltage is 90Vrms, the big capacitor C 903 voltage Vc903 of power frequency filtering are about about 120V, this moment, transformer T903Np3 winding was coupled to voltage Vnp3=120V/Np1 (Np1 represents this winding number of turns), hypothesis: Np1=50 encloses earlier, D901 forward conduction voltage Vf=0.7V, the Q903 crystal is guaranteed adequate food and is closed conduction voltage drop Vce=0.3V, Rs=0.68 ,, R911=10
Figure 609001DEST_PATH_IMAGE002
, then this moment, the PWMICCS end obtained the OPP bucking voltage
△V1=(Vnp3-Vf-Vce)*(Rs+R901)/(R911+R906+R901+Rs)
=1.4V* (0.68+R901)/(10.68+R901+R906); When power input voltage is 264Vrms, the big capacitor C 903 voltage Vc903 of power frequency filtering are about about 370V, this moment, transformer T903Np3 winding was coupled to voltage Vnp3=370V/Np1 (Np1 represents this winding number of turns), and then this moment, the PWMICCS end obtained the OPP bucking voltage
△V2=(Vnp3-Vf-Vce)*(Rs+R901)/(R911+R906+R901+Rs)
=6.4V* (0.68+R901)/(10.68+R901+R906); OPP Overpower compensating voltage was about input 4.57 times during 90Vrms when △ V2/ △ V1=4.57 was power input voltage 264Vrms, by adjusting R906 and R901 resistance size power input voltage OPP overpower protection point between 90Vrms-264Vrms was close again.
Three, the effect of each part in the OPP Overpower compensating circuit:
R911 resistance is placed on D901 rectifier diode anode, has better EMI and suppresses effect;
The D901 diode plays rectified action in the middle of circuit;
C901/C904/C905 electric capacity is used as the assorted fast of filtering high frequency;
R907/R908 resistance is as the divider resistance between Q903PNP transistor base and the emitter;
R910/R909 is a Q902MOS switching tube grid divider resistance;
R906 is for adjusting OPP Overpower compensating resistance;
R901 is promptly as OPP Overpower compensating resistance, again and C901 electric capacity form the RC low-pass filter circuit and prevent that the assorted fast PWMICCS of interfering with between the Q901/Rs from holding;
Q902 and Q903 transistor are done the switching tube that control OPP compensating circuit is opened and turn-offed, and wherein: Q902 is the N-channel MOS pipe, and also available NPN transistor substitutes; Q903 is the PNP transistor, and also available P channel MOS tube substitutes.
The above only is preferred embodiment of the present utility model, and all equalizations of being done according to the utility model claim change and modify, and all should belong to covering scope of the present utility model.

Claims (5)

1. the device of the flyback power supply Overpower compensating of one kind wide voltage input, the inverse-excitation type transformer (T901) that comprises flyback power supply, OPP Overpower compensating circuit, and as flyback power supply PWM control IC, it is characterized in that: described inverse-excitation type transformer (T901) comprising:
One primary side Np1 winding, its end of the same name (p11) is connected with the big capacitance cathode end of C903 power frequency, and different name end (p12) is connected with the drain electrode of MOS switching tube Q901;
One primary side Np2 winding, its end of the same name is connected with reference to ground with inverse-excitation type transformer (T901) primary side, and the different name end is connected with the Vcc power supply circuits;
One primary side NP3 winding, its different name end (p32) connect inverse-excitation type transformer (T901) primary side with reference to ground, and the other end is connected with OPP Overpower compensating circuit as end of the same name (p31);
Primary side Ns1, Ns2 ... the Nsn winding, its termination inverse-excitation type transformer of the same name (T901) primary side is with reference to ground, and the different name end is connected with output rectification circuit;
Described OPP Overpower compensating circuit output end be connected as flyback power supply PWM control IC, described pulse-width modulation output function end (Gate) as flyback power supply PWM control IC is connected with the grid of MOS switching tube Q901.
2. the device of the flyback power supply Overpower compensating of wide voltage input according to claim 1, it is characterized in that: the number of turns of described primary side NP3 winding is a circle.
3. according to the device of the flyback power supply Overpower compensating of the described wide voltage input of right 1; it is characterized in that: describedly comprise pulse-width modulation output function end (Gate) as flyback power supply PWM control IC; PWMIC function of supplying power end (Vcc); OPP exports overpower protection measuring ability end (CS); PWMIC detects output voltage feedback end (FB), and PWMIC connects with reference to ground end (GND).
4. the device of the flyback power supply Overpower compensating of wide voltage input according to claim 3, it is characterized in that: it is characterized in that: the inner that described PWMIC detects output voltage feedback end (FB) is connected with a pull-up resistor Rfb one end, and another termination of pull-up resistor Rfb one reference voltage V ref.
5. the device of the flyback power supply Overpower compensating of wide voltage input according to claim 1, it is characterized in that: described OPP Overpower compensating circuit is provided with the switching tube that a group transistor (Q902, Q903) is done OPP Overpower compensating circuit.
CN2010201243525U 2010-03-05 2010-03-05 Fly-back power supply overpower compensation device inputted by wide voltage Expired - Fee Related CN201608638U (en)

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Cited By (5)

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Publication number Priority date Publication date Assignee Title
CN101783595A (en) * 2010-03-05 2010-07-21 福建捷联电子有限公司 Overpower compensating method and device for wide voltage-input flyback power supply
CN102035170A (en) * 2011-01-18 2011-04-27 福建捷联电子有限公司 PFC output overvoltage protection circuit
CN102892239A (en) * 2012-10-31 2013-01-23 杭州士兰微电子股份有限公司 Flyback constant-current driving circuit and flyback constant-current driving control system containing flyback constant-current driving circuit
CN113725820A (en) * 2021-05-31 2021-11-30 杰华特微电子股份有限公司 Over-power protection method and protection circuit of flyback converter and flyback converter
EP3972107A4 (en) * 2020-03-18 2022-09-07 Shenzhen Huntkey Electric Co., Ltd. Switching power supply, power supply adapter, and charger

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101783595A (en) * 2010-03-05 2010-07-21 福建捷联电子有限公司 Overpower compensating method and device for wide voltage-input flyback power supply
CN101783595B (en) * 2010-03-05 2012-12-26 福建捷联电子有限公司 Overpower compensating method and device for wide voltage-input flyback power supply
CN102035170A (en) * 2011-01-18 2011-04-27 福建捷联电子有限公司 PFC output overvoltage protection circuit
CN102035170B (en) * 2011-01-18 2013-06-12 福建捷联电子有限公司 PFC output overvoltage protection circuit
CN102892239A (en) * 2012-10-31 2013-01-23 杭州士兰微电子股份有限公司 Flyback constant-current driving circuit and flyback constant-current driving control system containing flyback constant-current driving circuit
EP3972107A4 (en) * 2020-03-18 2022-09-07 Shenzhen Huntkey Electric Co., Ltd. Switching power supply, power supply adapter, and charger
CN113725820A (en) * 2021-05-31 2021-11-30 杰华特微电子股份有限公司 Over-power protection method and protection circuit of flyback converter and flyback converter
CN113725820B (en) * 2021-05-31 2024-05-24 杰华特微电子股份有限公司 Over-power protection method and circuit for flyback converter and flyback converter

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