gt 1504 150khz,2apwmbuckswitchingregulator gmostechnologycrop. www.gmos -semi.com 1/9 the generaldescription gt1504isamonolithicintegratedcircuitthat providealltheactivefunctionsforastep-down switchingregulator,capableofdrivinga2aload without additionaltransistorcomponent.requiring aminimumnumberofexternalcomponent,the boardspacecanbesavedeasily.theexternal shutdownfunctioncanbecontrolledbyttllogic levelandthencome intostandby mode.the internal compensation makes feedback control havegoodlineandloadregulationwithoutexternal design. regarding protected function, thermal shutdownistopreventovertemperatureoperating fromdamage,andcurrentlimitisagainstover currentoperatingoftheoutputswitch.thegt1504 operatesataswitchingfrequencyof150khzthus allowingsmallersizedfiltercomponentsthanwhat would beneededwithlowerfrequencyswitching regulators.otherfeaturesincludeaguaranteed +4% toleranceonoutputvoltageunderspecified inputvoltageandoutputloadconditions,and+15% ontheoscillatorfrequency.theoutputversion includedfixed3.3v,5v,12v,andanadjustable type.thepackagesareavailableinastandard 8-leadsop8. features - - 3.3v,5v,12vandadjustableoutputversions adjustableversionoutputvoltagerange,1.23vto 37v+4%maxoverlineandloadcondiction - - - - - - - - - sop-8lpackages voltagemodenon-synchronouspwmcontrol thermal-shutdownandcurrent-limitprotection on/offshutdowncontrolinput inputvoltagerangeupto40v outputloadcurrent:2a 150khzfixedfrequencyinternaloscillator lowpowerstandbymode built-inswitchingtransistoronchip applications - - - - simplehigh-efficiencystep-down(buck)regulator efficientpreregulatorforlinearregulators on-cardswitchingregulators positivetonegativeconverter -batterycharger pin assignments sop - 8l 7 6 5 (topview) 1 2 3 4 v in out fb gnd 8 sd gnd gnd gnd pin descriptions name description v in operatingvoltageinput. out switching output. gnd ground . ?? fb outputvoltagefeedbackcontrol. sd on/off shutdown. ?? gt1504 150khz,2apwmbuckswitchingregulator gmostechnologycorp. www.gmos -semi.com 2/9 ordering information package blank: sop - 8l gt1504 outputversion xx x x packing blank:tube a : taping -adj:adjustable -33 :3.3v -50 :5.0v -12 :12v block diagram current source bias 1.235v reference 2.5v regulator 150khz osc. start up + + + _ thermal limit pre-driver comp comp output gnd sd v in fb 220mv 2a switch 200mv + _ amp comp
gt1504 150khz,2apwmbuckswitchingregulator gmostechnologycorp. www.gmos -semi.com 3/9 absolute maximum ratings symbol parameter rating unit v cc ? supplyvoltage +45 v v sd ??? on/offpininputvoltage -0.3to+25 v v fb ? feedbackpinvoltage -0.3to+25 v v out ? outputvoltagetoground -1 v p d ? powerdissipation internallylimited w t st ? storagetemperature -65to+150 o c t op ? operatingtemperature -40to+125 o c v op ? operatingvoltage +4.5to+25 v electrical characteristics (all output voltage versions) unless otherwise specified, v in =12v for 3.3v, 5v, adjustable version and v in =24v for the 12v version. i load = 0.2a symbol paramet er conditions min. typ. max. unit -50 i b ? feedbackbiascurrent v fb =1.3v ?? (adjustableversiononly) -10 -100 na 127 150 173 f osc ? oscillatorfrequency 110 173 khz fscp ?? oscillator frequency ofwhencurrentlimitoccurred shortcircuitprotect andv fb <0.55v ? 30 70 khz 1.4 v sat ?? saturation voltage ?? i out =1.5a no outside circuit ? v fb =0v force driver on ? 1.25 1.5 v max.dutycycle(on) v fb =0vforcedriveron ? 100 dc min.dutycycle(off) v fb =12vforcedriveroff ? 0 % 3.3 i cl ? current limit ? peakcurrent ? no outside circuit v fb =0forcedriveron ? 2.4 2.8 3.6 a output=0v no outside circuit v fb =12 force driver off ? -200 ua i l output=-1v output leakage ? current v in =24v -5 ma i q quiescentcurrent ? v fb =12forcedriveroff ? 5 10 ma 150 i stby standbyquiescent on/offpin=5v current ? v in =24v 70 200 ua v il low(regulatoron) - 0.6 v ih on/offpinlogicinput thresholdvoltage ???? high(regulatoroff) 2.0 1.3 - v i h on/offpinlogic inputcurrent ? v logic =2.5v(off) -0.01 i l on/offpininputcurrentv logic =0.5v(on) -0.1 -1 ua tjincreasing 175 ts overtemperature ??? shutdownthreshold tjdecreasing 150 gt1504 150khz,2apwmbuckswitchingregulator gmostechnologycorp. www.gmos -semi.com 4/9 electrical characteristics (continued) symbo l parameter conditions typ. limit unit fb ? v output feedback 5v gt1504 150khz,2apwmbuckswitchingregulator gmostechnologycorp. www.gmos -semi.com 5/9 typical performance characteristics typical performance characteristics normalizedoutputvoltage 5.10 5.05 5.00 4.95 4.90 -50 -25 0 25 50 75 100 125 junctiontemperature(oc) v in =20v, i load =2a normalized at t =25oc j output current io (a) switch current limit 15.0 10.0 5.0 0.0 -50 -25 0 operating quiescent current 25.0 20.0 25 50 75 100 125 junctiontemperature(oc) junction temperature(oc) efficiency 95 90 85 80 75 70 8 10 15 20 25 30 35 40 2a load 5v 3.3v 1.7 1.6 1.5 1.4 1.3 1.2 2.0 3 4 5 switch current(a) 1 2 3 1 : - 40 oc 2 : 25 oc 3 : 125 o c switch saturation voltage 8.0 6.0 4.0 2.0 0.0 0 1 2 3 4 5 6 7 10 20 30 40 supplyvolotage(v) 100.0 80.0 40.0 0.0 shutdown quiescent current 200.0 130.0 v on/off =5v 1 : - 40 oc 2 : 25 3:125 oc oc 1 3 2 switch on switch off 10 0 =10v 20v 30v v in gt1504 150khz,2apwmbuckswitchingregulator gmostechnologycorp. www.gmos -semi.com 6/9 typical performance characteristics (continued) junction temperature(oc) 1.4 5 10 15 20 22 23 24 25 on/offpinvoltage(v) feedbackpinbiascurrent on/off pin current (sinking) 150.0 120.0 90.0 60.0 30.0 0.0 v in =40v - 40oc t j 125oc 50.0 40.0 30.0 20.0 10.0 0.0 -50 -25 0 25 50 75 100 125 adjustable version only 1.0 0.0 minimum operating supply voltage 5.0 4.0 3.0 2.0 -50 -25 0 25 50 75 100125 junctiontemperature(oc) v out =1.23v i load =120ma junction temperature (oc) on/off threshold voltage 5.0 4.0 3.0 2.0 1.0 0.0 - 50 -25 0 25 50 75 100 125 switch frequency junction temperature (oc) 200 150 100 - 50 - 25 0 25 50 75 100 125 thermal protection 10 8 6 4 2 0 junctiontemperature( 50 75 100 125 150 175 200 o c) tsc off tsd on 50 0.0
gt1504 150khz,2apwmbuckswitchingregulator gmostechnologycorp. www.gmos -semi.com 7/9 typical application circuit 1 4 2 5 3 12v dcinput vin c in capacitor fb sd out d1 schottky inductor diode gnd gt1504 -adj co 470uf capacitor l1 3.3v/2a output load 8 7 6 39uh r1 1% r2 1% somestandardvalueofr 1 andr 2 formostcommonlyusedoutputvoltagearelistedbelow. vin(v)/vo(v) r 1 (k ? ) r 2 (k ? ) l 1 minimum 24/12 17.6 2 68uh 12/5.0 6 2 33uh 12/3.3 3.3 2 33uh 12/2.5 2 2 27uh 12/1.8 0.91 2 22uh 5.0/3.3 3.4 2 33uh 5.0/2.5 2.1 2 27uh 5.0/1.8 0.95 2 22uh function description pin functions +v in thisisthepositiveinputsupplyfortheicswitchingregulator.asuitableinputbypasscapacitormustbe presentatthispintominimizevoltagetransientsandtosupplytheswitchingcurrentsneededbythe regulator. out internalswitchandpoweroutput.thevoltageatthispinswitchesbetween(+v in v sat )andapproximately 0.5v,withadutycycleofapproximatelyv out /v in . thepcboardcopperareaconnectedtothispinshould bekeptaminimuminordertoreducethecouplingsensitivitytothecircuitry ground circuitground. feedback completethefeedbackloopbysensingtheregulatedoutputvoltage on /off allowstheswitchingregulatorcircuittobeshutdownusinglogiclevelsignalsthusdroppingthetotalinput gt1504 150khz,2apwmbuckswitchingregulator gmostechnologycorp. www.gmos -semi.com 8/9 supplycurrenttoapproximately100ua.pullingthispinbelowathresholdvoltageofapproximately1.3v turnstheregulatoron,andpullingthispinabove1.3v(uptoamaximumof25v)shutstheregulatordown. ifthisshutdownfeatureisnotneeded,the on /off pin must be wired to the ground pin, in either case the regulatorwillbeintheoncondition. thermalconsiderations thesop-8packageneedsaheatsinkundermostcondictions.thesizeoftheheatsinkdependsonthe inputvoltage,theoutputvoltage,theloadcurrentandtheambienttemperature.thegt1504junction temperaturerisesaboveambienttemperaturefora2aloadanddifferentinputandoutputvoltages. the dataforthesecurves was takenwiththegt1504operatingasabuckswitchingregulatorinanambient temperatureof25c(stillair).thesetemperatureincrementsareallapproximateandareaffectedbymany o factors.someofthesefactorsincludeboardsize, shape,thickness,position,location,andevenboard temperature.otherfactorsaretracewidth,totalprintedcircuitcopperarea,copperthickness,singleor double-sided,multi-layerboardandamountofsolderontheboard.higherambienttemperaturesrequire moreheatsinking. forthebestthermalperformance,widecoppertracesandgenerousamountsofprintedcircuitboardcopper shouldbeusedintheboardlayout.(oneexceptionistheout(switch)pin,whichshouldnothavelargeareas ofcopper.)largeareasofcopperprovidethebesttransferofheat(lowerthermalresistance)tothe surroundingair,andmovingairlowersthethermalresistanceevenfurther. theeffectivenessofthepcboardtodissipateheatalsodependsonthesize,quantityandspacingofother componentsontheboard,aswellaswhetherthesurroundingairisstillormoving.furthermore,someof thesecomponentssuchasthecatchdiodewilladdheattothepcboardandheatcanvaryastheinput voltagechanges.fortheinductor,dependingonthephicalsize,typeofcorematerialandthedcresistance, itcouldeitheractasaheatsinktakingheatawayfromtheboard,oritcouldaddheattotheboard. marking information (1)sop-8l g t 1504 - xx ( top view ) outputtype: 1504 - adj: adj 1504-33:3.3v 1504-50:5.0v 1504-12:12v logo id code year: "04" = 2004 "03" = 2003 yy ww ~ xth week: 01~52
gt1504 150khz,2apwmbuckswitchingregulator gmostechnologycorp. www.gmos -semi.com 9/9 package information (1) package type: sop - 8l 0.015x45 l view"a" b e y 7 (4x) d 7 (4x) view"a" dimensions in millimeters dimensions in inches symbol min. nom. max. min. nom. max. a 1.40 1.60 1.75 0.055 0.063 0.069 a1 0.10 ? 0.25 0.040 ? 0.100 a2 1.30 1.45 1.50 0.051 0.057 0.059 b 0.33 0.41 0.51 0.013 0.016 0.020 c 0.19 0.20 0.25 0.0075 0.008 0.010 d 4.80 4.85 5.05 0.189 0.191 0.199 e 3.80 3.91 4.00 0.150 0.154 0.157 e ? 1.27 ? ? 0.050 ? h 5.79 5.99 6.20 0.228 0.236 0.244 l 0.38 0.71 1.27 0.015 0.028 0.050 y ? ? 0.10 ? ? 0.004 0 o ? 8 o 0 o ? 8 o
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