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SE517220C2 - Synchronous flyback converter - Google Patents

Synchronous flyback converter

Info

Publication number
SE517220C2
SE517220C2 SE9804454A SE9804454A SE517220C2 SE 517220 C2 SE517220 C2 SE 517220C2 SE 9804454 A SE9804454 A SE 9804454A SE 9804454 A SE9804454 A SE 9804454A SE 517220 C2 SE517220 C2 SE 517220C2
Authority
SE
Sweden
Prior art keywords
transistor
terminal
mosfet
collector
converter
Prior art date
Application number
SE9804454A
Other languages
Swedish (sv)
Other versions
SE9804454D0 (en
SE9804454L (en
Inventor
Bo Hedenskog
Claes Svaerdsjoe
Original Assignee
Ericsson Telefon Ab L M
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ericsson Telefon Ab L M filed Critical Ericsson Telefon Ab L M
Priority to SE9804454A priority Critical patent/SE517220C2/en
Publication of SE9804454D0 publication Critical patent/SE9804454D0/en
Priority to TW088116943A priority patent/TW456096B/en
Priority to EP99964889A priority patent/EP1145415A1/en
Priority to HK02105160.1A priority patent/HK1043447B/en
Priority to CNB99814777XA priority patent/CN1135682C/en
Priority to CA002356187A priority patent/CA2356187A1/en
Priority to KR1020017007808A priority patent/KR20010093856A/en
Priority to JP2000590281A priority patent/JP2002534049A/en
Priority to AU30920/00A priority patent/AU3092000A/en
Priority to PCT/SE1999/002390 priority patent/WO2000038305A1/en
Publication of SE9804454L publication Critical patent/SE9804454L/en
Publication of SE517220C2 publication Critical patent/SE517220C2/en

Links

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M3/00Conversion of DC power input into DC power output
    • H02M3/22Conversion of DC power input into DC power output with intermediate conversion into AC
    • H02M3/24Conversion of DC power input into DC power output with intermediate conversion into AC by static converters
    • H02M3/28Conversion 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
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M3/00Conversion of DC power input into DC power output
    • H02M3/22Conversion of DC power input into DC power output with intermediate conversion into AC
    • H02M3/24Conversion of DC power input into DC power output with intermediate conversion into AC by static converters
    • H02M3/28Conversion 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
    • H02M3/325Conversion 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
    • H02M3/335Conversion 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
    • H02M3/33569Conversion 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 having several active switching elements
    • H02M3/33576Conversion 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 having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
    • H02M3/33592Conversion 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 having several active switching elements having at least one active switching element at the secondary side of an isolation transformer having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer

Landscapes

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

Abstract

In a continuous mode flyback converter having a synchronous switch (Q2) the drive pulse to the switch (Q2) on the secondary side is generated by an inverting buffer circuit being fed from the output voltage terminal. By using such an arrangement several advantages are obtained. Hence, the pulse generating circuit arrangement generates a drive signal to the synchronous switch which is independent of the input voltage and the drive losses can thereby be minimized.

Description

51 7 2 2 0 = - S1: 2 på sekundärsidan. FET-transistorn kan exempelvis vara direkt ansluten till en hjälplindning anordnad i serie med transfor- matorns sekundärlindning. En omvandlare utformad i enlighet med dessa principer beskrivs exempelvis i den svenska paten- tansökan nr 9801595-1. 51 7 2 2 0 = - S1: 2 on the secondary side. The FET transistor can, for example, be directly connected to an auxiliary winding arranged in series with the secondary winding of the transformer. A converter designed in accordance with these principles is described, for example, in Swedish patent application no. 9801595-1.

I sådana drivningsstrukturer, där en hjälplindning används kommer emellertid amplituden vid styret på FET:n på sekun- därsidan att bero på inspänningen, dvs spänningen som ansluts till primärsidan. Detta kommer att orsaka ytterligare driv- ningsförluster, eftersom drivningsamplituden måste utformas för den lägsta inspänningen i ett sådant fall. Detta är sär- skilt ett problem i tillämpningar där ett stort inspänningsin- tervall önskas. Vidare beskrivs andra DC-DC-omvandlare i en- lighet med teknikens ståndpunkt i WO 98/04028 och i wo 95/02918.However, in such drive structures, where an auxiliary winding is used, the amplitude at the handlebars of the FET on the secondary side will depend on the input voltage, ie the voltage connected to the primary side. This will cause further drive losses, as the drive amplitude must be designed for the lowest input voltage in such a case. This is especially a problem in applications where a large input range is desired. Furthermore, other DC-DC converters are described in accordance with the prior art in WO 98/04028 and in wo 95/02918.

Redogörelse för uppfinningen Det är ett syfte med föreliggande uppfinning att övervinna problemen såsom beskrivits ovan och att åstadkomma en flyback- omvandlare i en kontinuerlig mod som har en enkel konstruktion och som samtidigt är effektiv jämfört med omvandlare i enlig- het med teknikens ståndpunkt och som är särskilt väl lämpad för ett stort inspänningsintervall.Disclosure of the Invention It is an object of the present invention to overcome the problems as described above and to provide a flyback converter in a continuous mode which has a simple construction and which is at the same time efficient compared to transducers according to the prior art and which is particularly well suited for a large input voltage range.

Detta syfte och andra uppnås genom strömomvandlarna såsom angivna i de bilagda patentkraven.This object and others are achieved by the current converters as set out in the appended claims.

Således alstras en drivpuls av en inverterande buffert- krets, som matas från utspänningen. Genom att använda en sådan pulsalstrande krets blir drivsignalen till den synkrona om- kopplaren oberoende av inspänningen och drivförlusterna kan därigenom minimeras.Thus, a drive pulse is generated by an inverting buffer circuit, which is supplied from the output voltage. By using such a pulse generating circuit, the drive signal to the synchronous switch becomes independent of the input voltage and the drive losses can thereby be minimized.

Kortfattad beskrivning av ritninqarna Föreliggande uppfinning kommer nu att beskrivas närmare med hjälp av icke begränsande exempel och med hänvisning till de bilagda ritningarna, på vilka: - fig 1 är ett kretsschema över en DC-DC-omvandlare i kon- tinuerlig mod, - fig 2a - 2c år tidsdiagram. 'i VEEIÉ ' I šWi HIFK? EI " .Iïí 517 220 zf: 3 Beskrivninq av föredraqna utförinqsformer I fig 1 visas en DC-DC-omvandlare. Strömomvandlaren inne- fattar, på primärsidan, en primârlindning 101 och en omkoppla- re 103. Primärlindningen matas med ström från en likspän- ningskälla 105. Omkopplaren kan exempelvis vara en n-kanal MOSFET-transistor Q1 såsom visas i figuren. Transistorns Q1 kollektoranslutningsklâmma är ansluten till en första anslut- ningsklâmma på primárlindningen 101 och emittern är ansluten till lågspànningsinanslutningsklämman på spänningskâllan 105.Brief Description of the Drawings The present invention will now be described in more detail by means of non-limiting examples and with reference to the accompanying drawings, in which: - Fig. 1 is a circuit diagram of a DC-DC converter in continuous mode, - Fig. 2a - 2c year time chart. 'i VEEIÉ' I šWi HIFK? Description of Preferred Embodiments Fig. 1 shows a DC-DC converter. The current converter comprises, on the primary side, a primary winding 101 and a switch 103. The primary winding is supplied with current from a direct voltage. The switch may be, for example, an n-channel MOSFET transistor Q1 as shown in Fig. The collector terminal of the transistor Q1 is connected to a first terminal of the primary winding 101 and the emitter is connected to the low voltage terminal of the voltage terminal 105.

Omkopplaren styrs av en styranordning (ej visad) ansluten till styret på transistorn Q1 och är anordnad att slà till och från transistorn Q1 vid önskade tidpunkter. Styranordningen kan ex- empelvis få styrdata från utanslutningsklàmmorna på omvandla- res sekundärsida.The switch is controlled by a control device (not shown) connected to the control of the transistor Q1 and is arranged to switch on and off the transistor Q1 at desired times. The control device can, for example, receive control data from the connection terminals on the secondary side of the converter.

Likspånningskâllan 105 kan i sin tur vara ansluten till en växelspânningsmatning (ej visad) via en likriktarkrets. Pri- mârsidan matar en sekundârsida med energi via en transformator M2. Sekundârsidan innefattar en sekundärlindning 101 med en motsatt lindningsriktning än lindningen på primärsidan.The DC voltage source 105 may in turn be connected to an AC power supply (not shown) via a rectifier circuit. The primary side supplies a secondary side with energy via an M2 transformer. The secondary side comprises a secondary winding 101 with an opposite winding direction than the winding on the primary side.

En första anslutningsklämma 111 på lindningen 109 är anslu- ten till en första anslutningsklämma 113 på en resistor R1, emittern 115 på en PNP-transistor Q3 och till en första an- slutningsklämma 117 på en utkondensator CO. Den andra anslut- ningsklämman 119 på resistorn R1 är ansluten till en första anslutningsklämma 121 på en resistor R2, vars andra anslut- ningsklämma 123 är ansluten till en andra anslutningsklämma 125 på lindningen 109.A first terminal 111 on the winding 109 is connected to a first terminal 113 of a resistor R1, the emitter 115 of a PNP transistor Q3 and to a first terminal 117 of an output capacitor CO. The second connection terminal 119 on the resistor R1 is connected to a first connection terminal 121 on a resistor R2, the second connection terminal 123 of which is connected to a second connection terminal 125 on the winding 109.

Basen 127 pà transistorn Q3 är ansluten till en punkt 129 mellan den andra anslutningsklämman 119 på resistorn R1 och den första anslutningsklämman 121 på resistorn R2. Kollektorn 131 på transistorn Q3 är ansluten till kollektorn 133 på en NPN-transistor Q4.The base 127 of the transistor Q3 is connected to a point 129 between the second connection terminal 119 of the resistor R1 and the first connection terminal 121 of the resistor R2. The collector 131 of the transistor Q3 is connected to the collector 133 of an NPN transistor Q4.

Basen 135 på transistorn Q4 är i en föredragen utförings- form ansluten till lindningens 109 andra anslutningsklämma 125 via en resistor R3 och en kondensator Cl ansluten i serie.The base 135 of the transistor Q4 is in a preferred embodiment connected to the second connection terminal 125 of the winding 109 via a resistor R3 and a capacitor C1 connected in series.

Transistorns Q4 emitter 137 är ansluten till kondensatorns CO andra anslutningsklämma 139 och till emittern 141 på en FET- transistor Q2. Styret 143 på transistorn Q2 är anslutet till en punkt 145 mellan kollektoranslutningsklämmorna på transis- "I lïišïl' ïIIH' Éííilïš EE' IW 517 220 31; 4 torerna Q3 och Q4. Kollektorn på transistorn Q2 är ansluten till den andra anslutningsklämman 125 på lindningen 109. En last ZL kan vara ansluten mellan anslutningsklâmmorna på ut- kondensatorn CO.The emitter 137 of the transistor Q4 is connected to the second terminal 139 of the capacitor CO and to the emitter 141 of a FET transistor Q2. The gate 143 of the transistor Q2 is connected to a point 145 between the collector connection terminals of the transistors Q3 and Q4. The collector of the transistor Q2 is connected to the second connection terminal 125 on the winding terminal 109 A load ZL can be connected between the connection terminals of the output capacitor CO.

Vid drift lagras under tillslagstiden på Q1, dvs då sty- ranordningen gör MOSFET-transistorn ledande, energi i trans- formatorns M2 kärna. På grund av lindningsriktningen kommer en positiv spänning att skapas vid transistorns Q2 kollektoran- slutningsklämma. Transistorn Q4 kommer samtidigt att vara le- dande och transistorn Q2 kommer därför att vara fránslagen.During operation, during the switch-on time of Q1, ie when the control device makes the MOSFET transistor conductive, energy is stored in the core of the transformer M2. Due to the winding direction, a positive voltage will be created at the collector connection terminal of the transistor Q2. Transistor Q4 will be conductive at the same time and transistor Q2 will therefore be switched off.

Dà transistorn Ql är fránslagen av styranordningen kastas polariteten i lindningarna i transformatorn M2 om på grund av energin som är lagrad i kärnan på transformatorn M2. De omvän- da polariteterna kommer att orsaka att en negativ spänning alstras vid transistorns Q2 emitteranslutningsklämma. Via spänningsdelaren som skapas av resistorerna Rl och R2 kommer den omvända polariteten på sekundârsidan att få transistorn Q3 att leda. Då transistorn Q3 börjar att leda gär styreanslut- ningsklämman 143 pà transistorn Q2 hög och transistorn Q2 bör- jar att leda. Kondensatorn Cl och resistorn R3 är anordnade så att frånslags- och tillslagstiderna för transistorn Q3 blir låga.When the transistor Q1 is switched off by the control device, the polarity of the windings in the transformer M2 is reversed due to the energy stored in the core of the transformer M2. The inverted polarities will cause a negative voltage to be generated at the emitter terminal of the transistor Q2. Via the voltage divider created by the resistors R1 and R2, the reverse polarity on the secondary side will cause the transistor Q3 to conduct. When transistor Q3 begins to conduct, the control terminal 143 of transistor Q2 goes high and transistor Q2 begins to conduct. The capacitor C1 and the resistor R3 are arranged so that the switch-off and switch-on times of the transistor Q3 are low.

I fig 2a - 2c visas ett tidsschema för kretsen som visas i fig 1. Således visas i fig 2a spänningen som finns vid styret på transistorn Q1.Figs. 2a - 2c show a timing diagram for the circuit shown in Fig. 1. Thus, Fig. 2a shows the voltage present at the gate of the transistor Q1.

I fig 2b visas spänningen som finns mellan anslutningskläm- morna på sekundärlindningen på transformatorn M2 vid motsva- rande tidpunkter. I fig 2c visas spänningen som finns mellan styret och emitterranslutningsklämman på transistorn Q2 vid motsvarande tidpunkter.Fig. 2b shows the voltage present between the connection terminals on the secondary winding of the transformer M2 at corresponding times. Fig. 2c shows the voltage present between the gate and the emitter terminal of the transistor Q2 at corresponding times.

Genom att skapa ett arrangemang där en drivpuls till FET- transistorn på sekundârsidan alstras av en inverterande buf- fertkrets som matas frán utspänningsanslutningsklämman åstad- koms således flera fördelar. Sålunda alstrar pulsalstrings- kretsarrangemanget en drivsignal till den synkrona omkopplaren som är oberoende av inställningen och drivningsförlusterna kan därigenom minimeras.By creating an arrangement where a drive pulse to the FET transistor on the secondary side is generated by an inverting buffer circuit which is fed from the output voltage terminal, several advantages are thus achieved. Thus, the pulse generating circuit arrangement generates a drive signal to the synchronous switch which is independent of the setting and the drive losses can thereby be minimized.

.Z ï: flíïï M "Ilïï 517 220 5 Vidare krävs ingen hjälplindning pä sekundârsidan såsom krävs i den svenska patentansökan nr 9801595-1, vilket kan va- ra en fördel i vissa tillämpningar..Z ï: flíïï M "Ilïï 517 220 5 Furthermore, no auxiliary winding on the secondary side is required as required in Swedish patent application No. 9801595-1, which may be an advantage in certain applications.

Uppfinningen är inte begränsad till implementationen som beskrivs i samband med fig 1, 2a, 2b och 2c, utan kan enkelt modifieras utan att avvika från de bilagda patentkravens om- fäng.The invention is not limited to the implementation described in connection with Figs. 1, 2a, 2b and 2c, but can be easily modified without departing from the scope of the appended claims.

Claims (2)

_vc_ :aug 517 220 6 Patentkrav (nva krav)_vc_: aug 517 220 6 Patent claim (nva claim) 1. Flybackomvandlare i kontinuerlig mod med en primär och en sekundär sida, varvid sekundàrsidan innefattar en MOSFET (Q2) med ett styrarrangemang som är anordnat att i beroende av omvandlarens utspänning styra MOSFETen (Q2), kånnetecknad av att styrarrangemanget innefattar en PNP-transistor (Q3), vars emitter är ansluten till omvandlarens ena utanslutningsklämma (117), och en NPN-transistor (Q4), vars emitter är ansluten till omvandlarens andra utanslutningsklämma (139), som ävenledes är ansluten till MOSFETens (Q2) emitter, att NPN- transistorns (Q4) kollektor är hopkopplad med PNP-transistorns (Q3) kollektor, att hopkopplingspunkten mellan kollektorerna (145) är ansluten till MOSFETens (Q2) styre (143), att PNP- transistorns (Q3) bas (127) är ansluten till hopkopplingspunkten mellan två resistorer (R1, R2) som bildar en spânningsdelare och som är seriekopplade mellan omvandlarens nämnda ena utanslutningsklämma (117) och MOSFETens (Q2) kollektor och att NPN-transistorns (Q4) bas (135) âr ansluten till MOSFETens (Q2) kollektor.A flyback converter in continuous mode with a primary and a secondary side, the secondary side comprising a MOSFET (Q2) with a control arrangement which is arranged to control the MOSFET (Q2) depending on the converter output voltage, characterized in that the control arrangement comprises a PNP transistor ( Q3), the emitter of which is connected to one terminal of the converter (117), and an NPN transistor (Q4), the emitter of which is connected to the second terminal of the converter (139), which is also connected to the emitter of the MOSFET (Q2), that the NPN the collector of the transistor (Q4) is connected to the collector of the PNP transistor (Q3), that the connection point between the collectors (145) is connected to the control (143) of the MOSFET (Q2), that the base (127) of the PNP transistor (Q3) is connected to the connection point between two resistors (R1, R2) which form a voltage divider and which are connected in series between the said one terminal of the converter (117) and the collector of the MOSFET (Q2) and that the base of the NPN transistor (Q4) (135 ) is connected to the MOSFET (Q2) collector. 2. Flybackomvandlaren enligt kravet 1, kânnetecknad av att NPN-transistorns (Q4) bas (135) är ansluten till MOSFETens (Q2) kollektor via en resistor (R3) i serie med en kondensator (C1). 'šïš I' IW' EUHEÉ E! -íïlšThe flyback converter according to claim 1, characterized in that the base (135) of the NPN transistor (Q4) is connected to the collector of the MOSFET (Q2) via a resistor (R3) in series with a capacitor (C1). 'šïš I' IW 'EUHEÉ E! -íïlš
SE9804454A 1998-12-21 1998-12-21 Synchronous flyback converter SE517220C2 (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
SE9804454A SE517220C2 (en) 1998-12-21 1998-12-21 Synchronous flyback converter
TW088116943A TW456096B (en) 1998-12-21 1999-10-01 A synchronous flyback converter
PCT/SE1999/002390 WO2000038305A1 (en) 1998-12-21 1999-12-16 A synchronous flyback converter
CNB99814777XA CN1135682C (en) 1998-12-21 1999-12-16 Synchronous Flyback Converter
HK02105160.1A HK1043447B (en) 1998-12-21 1999-12-16 A synchronous flyback converter
EP99964889A EP1145415A1 (en) 1998-12-21 1999-12-16 A synchronous flyback converter
CA002356187A CA2356187A1 (en) 1998-12-21 1999-12-16 A synchronous flyback converter
KR1020017007808A KR20010093856A (en) 1998-12-21 1999-12-16 A synchronous flyback converter
JP2000590281A JP2002534049A (en) 1998-12-21 1999-12-16 Synchronous flyback converter
AU30920/00A AU3092000A (en) 1998-12-21 1999-12-16 A synchronous flyback converter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE9804454A SE517220C2 (en) 1998-12-21 1998-12-21 Synchronous flyback converter

Publications (3)

Publication Number Publication Date
SE9804454D0 SE9804454D0 (en) 1998-12-21
SE9804454L SE9804454L (en) 2000-06-22
SE517220C2 true SE517220C2 (en) 2002-05-07

Family

ID=20413780

Family Applications (1)

Application Number Title Priority Date Filing Date
SE9804454A SE517220C2 (en) 1998-12-21 1998-12-21 Synchronous flyback converter

Country Status (10)

Country Link
EP (1) EP1145415A1 (en)
JP (1) JP2002534049A (en)
KR (1) KR20010093856A (en)
CN (1) CN1135682C (en)
AU (1) AU3092000A (en)
CA (1) CA2356187A1 (en)
HK (1) HK1043447B (en)
SE (1) SE517220C2 (en)
TW (1) TW456096B (en)
WO (1) WO2000038305A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100568319B1 (en) * 2004-10-22 2006-04-05 삼성전기주식회사 Flyback Converter with Synchronous Rectifier
CN101682264B (en) * 2007-05-30 2013-01-02 宝威意大利股份公司 Multi-output synchronous flyback converter
CN101359873B (en) * 2007-08-02 2010-09-08 洋鑫科技股份有限公司 Flyback Voltage Converter with Self-Driven Synchronous Rectifier
AT14080U1 (en) * 2013-08-12 2015-04-15 Tridonic Gmbh & Co Kg Control circuit for a control gear for bulbs

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3422777A1 (en) * 1984-06-20 1986-01-02 ANT Nachrichtentechnik GmbH, 7150 Backnang Controlled rectifier element, which is connected to an inductor, and its use
US4870555A (en) * 1988-10-14 1989-09-26 Compaq Computer Corporation High-efficiency DC-to-DC power supply with synchronous rectification
JP2845188B2 (en) * 1995-12-11 1999-01-13 サンケン電気株式会社 DC-DC converter
US5818704A (en) * 1997-04-17 1998-10-06 International Rectifier Corporation Synchronizing/driving circuit for a forward synchronous rectifier

Also Published As

Publication number Publication date
CN1135682C (en) 2004-01-21
EP1145415A1 (en) 2001-10-17
SE9804454D0 (en) 1998-12-21
HK1043447B (en) 2004-12-03
SE9804454L (en) 2000-06-22
TW456096B (en) 2001-09-21
JP2002534049A (en) 2002-10-08
KR20010093856A (en) 2001-10-29
CN1331863A (en) 2002-01-16
WO2000038305A9 (en) 2000-12-07
HK1043447A1 (en) 2002-09-13
AU3092000A (en) 2000-07-12
CA2356187A1 (en) 2000-06-29
WO2000038305A1 (en) 2000-06-29

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