BCD OFF LINE TECHNOLOGY The high level of integration of the L6590 family is made possible by the BCD OFF LINE technology Compared to other high voltage technologies BCD allows more design flexibil ity due to the large variety of components available: n high voltage N channel LDMOS 700V n medium voltage bipolar transistor 20V both NPN and PNP type n low and medium voltage CMOS devices to 10V n zener voltage references n resistors and capacitors Figure BCD Off line Cross Sections

Claudio Adragna

Description

Niveau: Secondaire, CAP
1/28 AN1261 APPLICATION NOTE May 2001 BCD OFF-LINE TECHNOLOGY The high level of integration of the L6590 family is made possible by the BCD OFF-LINE technology. Compared to other high voltage technologies, BCD allows more design flexibil ity due to the large variety of components available: n high voltage N-channel LDMOS (700V) n medium voltage bipolar transistor (20V, both NPN and PNP type) n low and medium voltage CMOS devices (5 to 10V) n zener voltage references n resistors and capacitors. Figure 1. BCD Off-line Cross Sections CMOS POLY1 - POLY2 CAP Pch. Nch. H.V. LDMOS L.V. LDMOS NPN LPNP D SG DG B E C B C E DG D G S S S by Claudio Adragna GETTING FAMILIAR WITH THE L6590 FAMILY HIGH-VOLTAGE FULLY INTEGRATED POWER SUPPLY In offline switchers in general and in low power ones in particular, the driving factors when making a design are reduction of cost, component count, size, weight as well as design to market. The monolithic or ”one-chip” solution, where PWM control and power switch are integrated on the same sil- icon and/or housed in the same package, looks very attractive especially in low power applications, where the typical approach, with separate PWM IC and power switch, features the higher cost-per-watt.

• pgnd pgnd


• power ac-dc


• vcc


• start-up generator


• pwm standby


• voltage power


• vcc voltage


• drain


• pin

Informations

• Publié par: profil-vauh-2012
• Nombre de lectures: 82
• Langue: English

Extrait

AN1261 APPLICATIONNOTE HIGH-VOLTA G G E E T F TI U N L G LY FA IN MI T L E IA G R RA W T IT E H D T P H O E W L6 E 5 R 90 S F U A P M P I L L Y Y byClaudioAdragna Inofflineswitchersingeneralandinlowpoweronesinparticular,thedrivingfactorswhenmakingadesign arereductionofcost,componentcount,size,weightaswelasdesigntomarket. Themonolithicorºone-chipºsolution,wherePWMcontrolandpowerswitchareintegratedonthesamesil- iconand/orhousedinthesamepackage,looksveryattractiveespecialyinlowpowerapplications,where thetypicalapproach,withseparatePWMICandpowerswitch,featuresthehighercost-per-watt.Amono- lithicsolution,whichalowstobuildanSMPSwithveryfewexternalparts,hasinthiscaseadramaticimpact. Ontheotherhand,theflexibilityoftheºtwo-chipºapproachdoesnotprovidesignificantadvantagesinsuch systemswherenosophisticatedfunctionalityisnormalyrequired.Additionaly,themonolithicapproachim- provessystemreliabilityandreducesdesigneffort. ThisapplicationnotedescribesindetailstheL6590andtheL6590A,asetofintegratedmonolithicswitching regulatorsforofflineconverters.AfterabriefdescriptionofBCDOFFLINE,thetechnologyusedforthese devices,theirinternalarchitectureandfunctionalitywilbedescribedindetails,thenanumberofapplication ideasandapplicationexampleswilbeprovided. BCDOFF-LINETECHNOLOGY ThehighlevelofintegrationoftheL6590familyismadepossiblebytheBCDOFF-LINEtechnology.Comparedto otherhighvoltagetechnologies,BCDallowsmoredesignflexibilityduetothelargevarietyofcomponentsavailable: n highvoltageN-channelLDMOS(700V) n mediumvoltagebipolartransistor(20V,bothNPNandPNPtype) n lowandmediumvoltageCMOSdevices(5to10V) n zenervoltagereferences n resistorsandcapacitors. Figure1.BCDOff-lineCrossSections DGSSGDBECBCE May2001 H.V.LDMOSL.V.LDMOSNPN SGDDGS Pch.Nch. CMOSPOLY1-POLY2CAP PNPL 82/1

AN1261APPLICATIONNOTE Inthiswayitispossibletorealizecompactandrobustdesignsolutionsbyintegratingonthesamesiliconchip bothhighvoltagepowercomponentsandsophisticatedcontrolandprotectionfunctions. Standardjunctionisolationisused,asshowninthecrosssectionofthetechnologyinFigure1.Thewasteof siliconareaduetolateraldiffusioninthickepitaxiallayers,normallyrequiredforhighvoltagecapability,iselim- inatedwiththeso-calledRESURF(ReducedSurfaceField)approach.ThistechniqueallowstheICtowithstand highvoltagesinverythinepitaxiallayers( ≤ 10 m m). TheRESURFapproachimplieslateralcurrentflowinthehighvoltageDMOS,sothisdevicehasalateralstruc- ture.Asaresult,thesubstrateoftheICisgroundedandthereismuchlessnoisegenerationcomparedtoa discreteFET. GENERALDEVICEDESCRIPTION Thisfamilyisasetofmonolithicswitchingregulatorsabletooperatewithaverywiderangeofinputvoltageand primarilyintendedforFlyback,BoostorForwardtopologiesinofflineapplications.Thepowerthatthedevices areabletohandleisinexcessof10Win110VacorWideRangeMains(WRM)applicationsandfrom15to20W in220Vacmainsapplications.Inthispowerrangeflybackisthemostcommontopology,soitwillbeconsidered asthereferencetopologyinthefollowing. Thefamilyincludesthreemembers:theL6590(housedinminidip),theL6590D(housedinSO16W)andthe L6590A(housedinminidip). Typically,theL6590andtheL6590Daresuitableforlow-powerAC-DCadapters,auxiliarypowersuppliesofCRTand LCDmonitorsandTV's.TheL6590Amaybeusedintheseapplicationsaswell,howeveritismorespecificforauxiliary powersuppliesofdesktopPC'sandservers.Allofthedevicescanbeusedalsotobuildbothhigh-voltageandlow- voltageDC-DCconverterssincetheyareabletooperatewithinputvoltagesaslowas40 . V Figure2.L6590FamilyInternalBlockDiagram D (1 R ) A [ I 1] N [x]:L6590D(SO16W) D ( R 1 A ) IN START-UP START-UP CCV (3 V ) C [ C 4] (3) THERMAL S & U U P V P L L O Y VREF T S H .D E O R W MA N L S & U U P V P L L O Y VO O L V T E A R GE SHUTDOWN + + - - OVP VREF SGND VREF ]5[ + BROWNOUT + + BROWNOUT + BOK KOB GND - OCP - 2.5V [6] (6 G ,7 N , D 8) - CUR O R V E E N R T - 2.5V (5) (6,7,8) STANDBY PWM STANDBY PWM PGND - VFB [9,...,16] 65/2 O 2 S k C Hz + (5)[8] 65/ O 22 S k C Hz 2.5V 1mA PMOC ( C 4 O )[ M 7] P (4) L6590/L6590DL6590A Figure2showstheinternalblockdiagramsofthedevices.Theinternalpowerswitchisrealisedwithalateral highvoltagepowerMOSFETwithatypicalR DS(on) of13 W andaV (BR)DSS of700V.Thefixedfrequency(65 kHz)internaloscillatorandthenon-dissipativestart-upallowtominimizetheexternalcomponentscount. ThePWMcontrolincorporatesavoltagemodecontrolschemeandconverter'soutputvoltageregulationcanbe achievedwithbothopto-isolatedandprimarysensingfeedback.Internalprotectionslikecycle-by-cyclecurrent 82/2