CN101359878B - Flyback voltage converter having self-driving synchronous rectifier - Google Patents

Flyback voltage converter having self-driving synchronous rectifier Download PDF

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Publication number
CN101359878B
CN101359878B CN2007101413590A CN200710141359A CN101359878B CN 101359878 B CN101359878 B CN 101359878B CN 2007101413590 A CN2007101413590 A CN 2007101413590A CN 200710141359 A CN200710141359 A CN 200710141359A CN 101359878 B CN101359878 B CN 101359878B
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synchronous rectifier
voltage
self
flyback converter
circuit
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CN101359878A (en
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王志良
余金生
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GLACIAL TECHNOLOGY Co Ltd
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GLACIAL TECHNOLOGY Co Ltd
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Abstract

The invention discloses a flyback converter with a self-driving synchronous rectifier which utilizes a transistor as a secondary rectifier to replace the traditional diode rectifier to lower the conduction loss. But the transistor is needed to be driven by suitable gate driver. Traditionally, a force driving gate driver is adopted realized by an integrated circuit with being complex and expensive, and an ordinary self-driving gate driver is still complex. The drive circuit of the flyback converter with the self-driving synchronous rectifier is formed that a secondary drive coil is connected in series with a diode, a switch controller and a switch to be taken as the self-driving gate driver, wherein, the switch controller decides the opening or the closing of the switch; a voltage detection circuit is utilized to be connected with the switch controller, and can detect the voltage of the synchronous rectifier which is connected with a secondary coil to control the switch controller; therefore, the flyback converter with the self-driving synchronous rectifier can efficiently simplify the complexity of the circuit and lower the cost.

Description

Flyback converter with self-driven synchronous rectifier
Technical field
The present invention particularly has the flyback converter of self-driving type synchronous rectifier about a kind of flyback converter.
Background technology
Traditional flyback converter (flyback converter) mainly utilizes transformer and diode as rectifier, is called diode rectifier again, in order to the power transfer of power supply to external load circuit.Transformer circuit has the primary coil (primary winding) and the secondary coil (secondary winding) of separation, wherein primary coil is in order to connect external power source, and secondary coil is an induction coil, magnetic flux (magnetic flux) in order to the inductive primary coil changes and living induced voltage, connect rectifier (rectifier) and form power circuit (power circuit), in order to drive external load circuit (load).
Please refer to Fig. 1, it is depicted as the circuit of traditional flyback converter.Transformer 10 has primary coil Lp and the secondary coil Ls that is separated from each other, and primary coil Lp is in order to connection external power source (power source), and secondary coil Ls behind power circuit (power circuit), connects external load circuit (load).Stain among the figure on primary coil Lp and the secondary coil Ls is represented same polarity (being negative or positive electrode simultaneously).
Secondary coil Ls connects diode D1 to form power circuit, and wherein diode D1 is called diode rectifier again in order to rectification.One output of power circuit is a voltage output end, and the other end is an earth terminal, and cross-over connection capacitor C o between voltage output end and earth terminal is called load capacitance (load capacitor).
At first introduce the supply power mode of external power source, its divide into usually continuous conduction mode (continuousconduction mode, CCM) and DCM (discontinuous conduction mode, DCM).Continuous conduction mode only is the special case of DCM, and DCM below is described.Wherein input voltage is powered with periodic manner, and the time is designated as t, and it is defined as follows:
1. be open period at first, be designated as T On(0<t<T On), inside and outside power supply is executed voltage V during this i(V i=HIGH) in primary coil L p, primary coil L pEnergy storage is by primary coil L pThe electric current of coil is cumulative to maximum, secondary coil L sNo current.
2. then for during resetting, be designated as T r(T On<t<T On+ T r), inside and outside power-off during this, secondary coil L sRelease energy, by the current i of secondary wire coil Ls sBy maximum decrescence to 0, primary coil L pReflected output voltage (reflected output voltage) N wherein pAnd N sDifference primary coil L pAnd secondary coil L sCoil number, primary coil L pElectric current
Figure G2007101413590D00022
Be formed at primary inductance and primary coil L pLoop in, but the current i by primary switch Sw(t)=0.
3. be timing period at last, be designated as T Dead=T s-T On-T r(T On+ T r<t<T s), T wherein sDuring expression switch one-period, power-off (V in inside and outside during this i=0), secondary coil L sNo longer release energy, no current is by primary coil L pAnd secondary coil L s
Do not reduce to 0 (releasing can be incomplete) when induced current, next cycle promptly begins, and then is called continuous conduction mode.Cooperate Fig. 1, below the start principle of explanation flyback converter.
In the open period, primary coil L pAnd secondary coil L sThe end points of last sign stain is a high-pressure side, diode D 1Be reverse biased, power circuit is conducting not, by load capacitance C oThe voltage V of external load circuit is provided o
During the replacement, primary coil L pAnd secondary coil L sThe end points of last sign stain is a low-pressure end, diode D 1Be forward bias voltage drop, the power circuit conducting, electric power is in load capacitance C oAnd external load circuit.
Timing period, primary coil L pAnd secondary coil L sOn voltage be 0, diode D 1Be reverse biased-V oClose, by load capacitance C oThe voltage V of external load circuit is provided o
The shortcoming of this kind flyback converter is that diode rectifier will cause serious conducting loss (conduction loss).For reducing the conducting loss, the general synchronous rectifier that adopts is to substitute diode rectifier, for example, mos field effect transistor (metal oxide semiconductor field effecttransistor, MOS) often be used as synchronous rectifier, it is implemented circuit and please refer to Fig. 2.
The circuit of comparison diagram 2 and flyback converter shown in Figure 1, its difference is in adopting n-MOS transistor (n type metal oxide semiconductor field-effect transistor) M 1Substitute diode, as synchronous rectifier, but this kind design needs with integrated circuit controller (controller) IC with control n-MOS transistor M 1Conducting.
Other has the design of similar flyback converter, please refer to Fig. 3, and it is in n-MOS transistor M with the different of Fig. 2 circuit 1Be connected in the earth terminal of loading coil.Flyback converter shown in Figure 3 is called low-pressure end and drives flyback converter (low side driven flyback converter), and the flyback converter of Fig. 2 circuit is called high-pressure side driving flyback converter (high side driven flybackconverter).This type of design has increased the complexity and the cost of circuit because of utilizing integrated circuit controller IC.
For reducing the complexity and the cost of conducting loss, circuit, utilize different circuit to make flyback converter, still have its demand.
Summary of the invention
A purpose of the present invention is to reduce the conducting loss of flyback converter, and it utilizes the conducting of synchronous rectifier with control secondary power coil.
Another object of the present invention is to reduce the complexity of flyback converter circuit, it utilizes secondary drive coil to connect an on-off controller, in order to receive the detection signal of voltage detecting circuit, on-off controller is according to the output signal of this detection signal control switch, and then synchronous rectifier is opened or closed in decision.
For reaching above-mentioned purpose, the flyback converter with self-driven synchronous rectifier of the present invention, it comprises transformer, diode, voltage detecting circuit, on-off controller, switch and synchronous rectifier.Transformer comprises primary coil, secondary drive coil and secondary power coil.Primary coil is in order to connect external power source.The secondary power coil connects synchronous rectifier and constitutes power circuit, and the output of power circuit comprises an earth terminal (low-pressure end), and an end is voltage output end (high-pressure side), cross-over connection output capacitance between voltage output end and earth terminal.Secondary drive coil serial connection diode, on-off controller and switch are to form drive circuit, on-off controller is connected in voltage detecting circuit to receive voltage signal, wherein voltage detecting circuit is in order to detect the voltage of power circuit, and transmit voltage signal and give on-off controller, in order to control switch, and then make switch open or close synchronous rectifier.
Description of drawings
Figure 1 shows that the circuit diagram of the flyback converter of prior art.
Figure 2 shows that the high-pressure side of prior art drives the circuit diagram of flyback converter.
The low-pressure end that Figure 3 shows that prior art drives the flyback converter circuit diagram.
Figure 4 shows that the flyback converter circuit diagram with self-driven synchronous rectifier of one embodiment of the invention.
Figure 5 shows that the drive circuit schematic diagram of the flyback converter with self-driven synchronous rectifier of one embodiment of the invention.
Figure 6 shows that the high-pressure side of one embodiment of the invention has the flyback converter circuit diagram of self-driven synchronous rectifier.
Figure 7 shows that the low-pressure end of one embodiment of the invention has the flyback converter circuit diagram of self-driven synchronous rectifier.
Figure 8 shows that the low-pressure end of one embodiment of the invention has the flyback converter circuit diagram of self-driven synchronous rectifier.
Figure 9 shows that the synchronous rectifier of one embodiment of the invention, wherein with PNP bipolar transistor and diode as synchronous rectifier.
Embodiment
Below conjunction with figs. is elaborated to illustrate spirit of the present invention to preferred embodiment of the present invention.
Please refer to Fig. 4, the kickback transformer of one embodiment of the invention shown in the figure (transformer) 100 circuit, it comprises primary coil (primary winding) L p, secondary drive coil (secondary drivingwinding) L dAnd secondary power coil (secondary power winding) L 1, primary coil L wherein pIn order to connect external power source Vi.
Secondary power coil L 1Connect power circuit (power circuit), the output of power circuit comprises voltage output end V 0(high-pressure side) and earth terminal (low-pressure end) are in order to the voltage of external load circuit (load) (not showing on the figure) to be provided, in voltage output end V 0And cross-over connection one load capacitance (load capacitor) C between earth terminal oIn order to voltage stabilizing.Secondary drive coil L dThe serial connection drive circuit, drive circuit connects voltage detecting circuit 500 and power circuit, respectively in order to receive detection signal and conducting or interrupting power circuit.
Voltage detecting circuit 500 detects the voltage of power circuit, and transmits detection signal and give drive circuit, and drive circuit is again according to this detection signal decision conducting or interrupting power circuit.
Fig. 5 is according to one embodiment of the invention explanation primary coil L p, secondary drive coil L d, drive circuit and voltage detecting circuit 500 schematic diagram.Drive circuit comprises diode D 2, on-off controller 400 and switch 200.On-off controller 400 has input 410, test side 430 and output 420, and switch 200 has the first voltage link 220, the second voltage link 230 and signal output part 240.
Secondary drive coil L dFirst end connect diode D 2Positive pole, diode D 2Negative pole connect the input 410 of on-off controller 400, the output 420 of on-off controller 400 connects the first voltage link 220 of switches 200, the side 430 of detecing of on-off controller 400 connects voltages and detects lateral circuit 500.The second voltage link 230 of switch 200 connects secondary drive coil L dSecond end and the inflow end of the synchronous rectifier on the power circuit, and the signal output part 240 of switch 200 connects the control end (not shown) of synchronous rectifiers, but so conducting or powered-down circuit.In addition, the input 410 and secondary drive coil L of on-off controller 400 dConnect capacitor C between second end 1, in order to voltage stabilizing and avoid on-off controller 400 suspension joints and undermined.
Voltage detecting circuit 500 can detect the inflow end of synchronous rectifier on the power circuit and the cross-pressure of outflow end, and in the present embodiment, it comprises two resistance R in parallel 3, R 4, connect the inflow end of synchronous rectifier and the voltage (not shown) of outflow end respectively, dimension level drive coil L dSecond end be connected in the inflow end of synchronous rectifier, so with resistance R 3Be connected in secondary drive coil L dSecond end, as shown in FIG..
When synchronous rectifier 300 conductings, flow into end 320 and outflow end 330 as short circuit, two resistance R of voltage detecting circuit 500 3, R 4 Send test side 430 electronegative potentials of on-off controller 400 to by parallel connected end, and make switch on-off controller 400 open switch 200; When synchronous rectifier 300 not conductings, flow into 330 of end 320 and outflow ends and be open circuit, and send test side 430 high potentials of on-off controller 400 to, and make switch on-off controller 400 off switch 200.
Fig. 6 is for having the primary coil L of the flyback converter of self-driven synchronous rectifier according to one embodiment of the invention explanation high-pressure side p, secondary drive coil L d, drive circuit, secondary power coil L 1, power circuit and voltage detecting circuit 500 schematic diagram.As shown in the figure, power circuit comprises synchronous rectifier 300, and synchronous rectifier 300 has control end 310, flows into end 320 and outflow end 330, secondary power coil L 1Connect to flow into and hold 320, outflow end 330 is connected to voltage output end V 0
The signal output part 240 of the switch 200 of drive circuit connects the control end 310 of synchronous rectifier 300, and the second voltage link 230 of switch 200 is connected in the inflow end 320 of synchronous rectifier 300 and second end of secondary power coil.
Voltage detecting circuit 500 is connected in the test side 430 of on-off controller 400, and it comprises two resistance R in parallel 3, R 4, be connected to the inflow end 320 and the outflow end 330 of the synchronous rectifier 300 of power circuit.
According to the foregoing description, in the power supply power-up period, utilize the change in voltage of the test side 430 of on-off controller 400, whether conducting of control input end 410 and output 420, so as to controlling the change in voltage of 230 of the first voltage link 220 and the second voltage links, and then the electric potential signal of the signal output part 240 of control switch 200.When synchronous rectifier 300 that signal output part 240 is connected on the power circuit, electric potential signal is with whether conducting of the inflow end 320 of may command synchronous rectifier 300 and outflow end 330.If the control end 310 of synchronous rectifier 300 is unlocked and the voltage that flows into end 320 when being higher than the voltage of outflow end 330, electric current flows to outflow end 330, secondary power coil L by flowing into end 320 1Can be via synchronous rectifier 300 chargings in load capacitance C oAnd driving external load circuit (not showing on the figure).When if the control end 310 of synchronous rectifier 300 is closed, flow into end 320 and outflow end 330 for opening circuit, power circuit forms not conducting, by load capacitance C oDrive external load circuit.
Fig. 7 is for having the primary coil L of the flyback converter of self-driven synchronous rectifier according to one embodiment of the invention explanation low-pressure end p, secondary drive coil L d, drive circuit, secondary power coil L 1, power circuit and voltage detecting circuit 500 schematic diagram.The power circuit that has the flyback converter of self-driven synchronous rectifier with high-pressure side is compared, the inflow end 320 that low-pressure end has the synchronous rectifier 300 in the power circuit of flyback converter of self-driven synchronous rectifier is serially connected with on the earth terminal (low-pressure end), and outflow end 330 connects secondary power coil L 1, control end 310 connects the signal output part 240 of switch 200.The power circuit of flyback converter that the open and close of the control end of present embodiment and high-pressure side have self-driven synchronous rectifier is identical, repeats no more in this.
Be noted that, in an embodiment, utilize N (P) type metal oxide semiconductor field-effect transistor (n/p-channel metal oxide semiconductor field effect transistor, n/p-MOS), N (P) type meets face field-effect semiconductor (p/n-channel junction field effecttransistor, p/n-JFET) or PNP (NPN) bipolar transistor (pnp/npn bipolar junctiontransistor, during pnp/npn-BJT) as synchronous rectifier, grid (base) utmost point is as control end 310, and defines respectively according to the characteristic of source transistor (emission) utmost point and leakage (current collection) utmost point and to flow into end 320 and outflow end 330.
For example, the synchronous rectifier that has the flyback converter of self-driven synchronous rectifier with n-MOS as high (low) pressure side, its control end 310, inflow end 320 and outflow end 330 are respectively the transistorized grid of n-MOS, source electrode and drain electrode, and voltage detecting circuit is the cross-pressure that detects the body diode (body diode) between the transistorized source-drain electrodes of n-MOS.
And for example, utilize PNP or npn type bipolar transistor as synchronous rectifier, cause is but the characteristic of the body diode of MOS transistor needs an external diode that cross-pressure is provided, and its connected mode is that the positive pole of diode and negative pole are connected inflow end 320 and outflow end 330 respectively.In an embodiment, when utilizing the positive-negative-positive bipolar transistor as synchronous rectifier, as control end 310, outflow end 330 and inflow end 320, hold cross-over connection diode between 320 (emitters) and the outflow end 330 (collector electrode) with its base stage, collector electrode and emitter in flowing into.
Then, Figure 8 shows that a low-pressure end has the circuit diagram of the flyback converter embodiment of self-driven synchronous rectifier.As shown in the figure, synchronous rectifier 300 is a n-MOS transistor M 2
Switch 200 with an interlock type circuit as, the interlock type circuit comprises a npn bipolar transistor Q 1, PNP bipolar transistor Q 2, two resistance R 1, R 2Transistor Q 1Emitter connect transistor Q 2Emitter and tie point be defined as signal output part 240.Two-transistor Q 1, Q 2Base stage join resistance R 1Be connected across transistor Q 1Collector electrode and base stage between, and resistance R 2Be connected across transistor Q 2Collector electrode and base stage between.Transistor Q 1And transistor Q 2Collector electrode be defined as the first voltage link 220 and the second voltage link 230 respectively.
On-off controller 400 is a PNP bipolar transistor Q 3, its emitter, base stage and collector electrode are defined as input 410, test side 430 and output 420 respectively.
Voltage detecting circuit 500 comprises two resistance R in parallel 3, R 4, parallel connected end is connected in test side 430 (the bipolar transistor Q of on-off controller 400 3Base stage), resistance R 3, R 4Be connected to the inflow end 320 and outflow end 330 (the n-MOS transistor M of synchronous rectifier 300 2Source electrode and drain electrode).
According to the conducting situation of the circuit in the one-period of power supply power supply, power supply power supply power-up period is divided into during open period, the replacement and timing period (definition is described in prior art).When using the foregoing description, its each interval conducting is described below:
Open period T On(0<t<T On): diode D 2Be subjected to reverse biased (reverse biased) and form and to open circuit capacitor C 1Execute voltage in bipolar transistor Q 3Emitter, divider resistance R 4With R 3Execute being biased in its base stage, because of n-MOS transistor M 2Body diode be subjected to reverse biased (reverse biased) and form and to open circuit, make its drain electrode be in high potential, and then make bipolar transistor Q 3Base potential be higher than its emitter current potential, bipolar transistor Q 3Emitter and base stage be subjected to reverse biased and close the bipolar transistor Q of switch 200 1Also close n-MOS transistor M 2Be closed.Even n-MOS transistor M 2Grid accumulate electric charge, transistor Q that also can be very fast via switch 200 2And resistance R 2And discharge, make n-MOS transistor M 2The cross-pressure of grid source two utmost points reduce to 0 (V GS=0), closes n-MOS transistor M 2, not conducting of power circuit is by output capacitance C oDrive the voltage V of external load circuit oTherefore, at open period T On(0<t<T On) in, electric current is by n-MOS transistor M 2Grid flow to transistor Q 2, promptly the signal output part 240 of switch 200 provides low voltage signal.
T during the replacement r(T On<t<T On+ T r): diode D 2Be subjected to forward bias voltage drop (forward biased) and conducting, because of n-MOS transistor M 2Body diode be subjected to forward bias voltage drop (forward biased) and conducting makes its drain electrode be in electronegative potential, divider resistance R 4With R 3Impose on bipolar transistor Q 3The voltage of base stage be lower than capacitor C 1Impose on bipolar transistor Q 3The voltage of emitter, bipolar transistor Q 3Emitter and base stage be subjected to forward bias voltage drop and conducting, the bipolar transistor Q of switch 200 1Also conducting, electric current is by the inflow end 220 of switch 200, via resistance R 1, turn-on transistor Q 1, and then providing high potential at the signal output part 240 of switch 200, this high potential makes n-MOS transistor M 2Be unlocked, thereby conducting n-MOS transistor M 2Source electrode (flow into end 320) and drain electrode (outflow end 330), power circuit forms path.Therefore, T during resetting r(T On<t<T On+ T r) in, electric current is by transistor Q 1Flow to n-MOS transistor M 2Grid, promptly the signal output part 240 of switch 200 provides high voltage signal.
Timing period T Dead(T On+ T r<t<T On+ T r+ T Dead): primary coil L p, secondary drive coil L dAnd secondary power coil L 1No longer release energy and no current and pass through, at this moment diode D 2No-bias and form and open circuit n-MOS transistor M 2Be closed, not conducting of power circuit is by output capacitance C oDrive the voltage V of external load circuit o
Another embodiment is when utilizing the PNP bipolar transistor as synchronous rectifier 300, needs external diode, and to produce the cross-pressure that flows into end 320 and outflow end 330, the embodiment of its synchronous rectifier as shown in Figure 9.
The principle that high-pressure side has the flyback converter of self-driven synchronous rectifier has the flyback converter of self-driven synchronous rectifier with low-pressure end, only notes that the polarity of synchronous rectifier need connect correctly, and this repeats no more.
In sum, utilize secondary drive coil to form one drive circuit, on-off controller on the drive circuit is subjected to the detection signal of voltage detecting circuit with control switch, and then can open or the powered-down circuit on synchronous rectifier, promptly utilize drive circuit to open or the powered-down circuit, so finish flyback converter with self-driven synchronous rectifier.
Above-described embodiment only is explanation technological thought of the present invention and characteristics, its purpose makes person skilled in the art scholar can understand content of the present invention and is implementing according to this, when not limiting claim of the present invention with it, be that every equalization of doing according to disclosed spirit changes or modification, must be encompassed in the claim of the present invention.

Claims (6)

1. flyback converter with self-driven synchronous rectifier comprises:
One kickback transformer has a primary coil, level drive coil and a secondary power coil, and wherein this primary coil connects an external power source so as to input voltage;
One power circuit, its this secondary power coil tandem one synchronous rectifier by this kickback transformer is constituted, so that a voltage output end and an earth terminal to be provided, and between this voltage output end and this earth terminal cross-over connection one electric capacity, wherein this synchronous rectifier has a control end, an inflow end and an outflow end, this inflow end is serially connected with this secondary power coil with this outflow end, and this control end receives a control signal with conducting or disconnect this inflows and hold and this outflow end;
One drive circuit, its this secondary drive coil by this kickback transformer is connected in series a diode, one on-off controller and a switch constitute, wherein this on-off controller has an input, one output and a test side, this switch has one first voltage link, one second a voltage link and a voltage signal output end, this switch first voltage link connects the output of this on-off controller, the input of this on-off controller connects the negative pole of this diode, the positive pole of this diode connects first end of this secondary drive coil, second end of this secondary drive coil connects this second voltage link of this switch and this inflow end of this synchronous rectifier, and this voltage signal output end of this switch connects this control end of this synchronous rectifier, in order to this control signal to be provided, and between second end of the input of this on-off controller and this secondary drive coil cross-over connection one second electric capacity, in order to voltage stabilizing; And
One voltage detecting circuit connects this test side and this power circuit of this on-off controller, in order to the inflow end that detects this synchronous rectifier and the cross-pressure between outflow end, and transmits detection signal and gives this on-off controller.
2. the flyback converter with self-driven synchronous rectifier according to claim 1, it is characterized in that it is a high-pressure side self-powered flyback converter or a low-pressure end self-powered flyback converter, wherein this synchronous rectifier is serially connected with and is called this high-pressure side self-powered flyback converter between this secondary power coil and this voltage output end, if be serially connected with between this secondary power coil and this earth terminal, then be called this low-pressure end self-powered flyback converter.
3. the flyback converter with self-driven synchronous rectifier according to claim 1 and 2 is characterized in that this switch comprises:
One npn bipolar transistor, the collector electrode and the base stage of one first this npn bipolar transistor of resistance cross-over connection, the collector electrode of this npn bipolar transistor is defined as this first voltage link; And
One PNP bipolar transistor, the collector electrode and the base stage of one second this PNP bipolar transistor of resistance cross-over connection, and base stage and emitter that the base stage and the emitter of this PNP bipolar transistor is connected to this npn bipolar transistor, wherein the collector electrode of this PNP bipolar transistor is defined as this second voltage link, and the tie point of two-transistor emitter is defined as this voltage signal output end.
4. the flyback converter with self-driven synchronous rectifier according to claim 1 and 2, it is characterized in that this synchronous rectifier is that N type metal oxide semiconductor field-effect transistor, P-type mos field-effect transistor, N type connect face type field-effect transistor, the P type connects face type field-effect transistor, npn bipolar transistor or PNP bipolar transistor, wherein npn bipolar transistor or PNP bipolar transistor need external one second diode.
5. the flyback converter with self-driven synchronous rectifier according to claim 1 and 2 is characterized in that this on-off controller is a PNP bipolar transistor, and its emitter, base stage and collector electrode are respectively this input, this test side and this output.
6. the flyback converter with self-driven synchronous rectifier according to claim 1 and 2, it is characterized in that this voltage detecting circuit is two resistance in parallel, its parallel connected end connects the test side of this on-off controller, and the other end of this two resistance connects this inflow end and this outflow end of this synchronous rectifier respectively.
CN2007101413590A 2007-07-30 2007-07-30 Flyback voltage converter having self-driving synchronous rectifier Expired - Fee Related CN101359878B (en)

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RU2481691C1 (en) * 2012-03-16 2013-05-10 Общество с ограниченной ответственностью "Гамем" (ООО "Гамем" Static converter
RU181943U1 (en) * 2018-02-21 2018-07-30 Общество с ограниченной ответственностью "Научно-производственное предприятие "ЦИКЛ ПЛЮС" (ООО НПП "ЦИКЛ ПЛЮС") Device for connecting a static converter to a DC voltage source

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CN1380739A (en) * 2001-04-10 2002-11-20 伊博电源(杭州)有限公司 Automatical driving circuit of low-voltage output synchronous rectifier

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Publication number Priority date Publication date Assignee Title
CN1380739A (en) * 2001-04-10 2002-11-20 伊博电源(杭州)有限公司 Automatical driving circuit of low-voltage output synchronous rectifier

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Title
JP平10-290567A 1998.10.27
JP平11-285245A 1999.10.15

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