page ?no. ?: ? 1/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com rs2138 ? high ? precision ? cc/cv ? primary \ side ? pwm ? power? switch ? ? general ? description ? rs2138? is ? a ? high? performance ? offline ? pwm ? power ? switch ? for ? low ? power ? ac/dc ? charger ? and? adaptor ? applications. ? it ? operates ? in ? primary \ side ? sensing ? and ? regulation. ? consequently, ? opto \ coupler ? and? 431? could ? be ? eliminated. ? proprietary ? constant ? voltage? (cv) ? and? constant ? current ? (cc) ? control ? is ? integrated ? as ? shown ? in ? the ? fig.1. ? ? in? cc? control, ? th e ? current ? and? output ? power ? setting ? can ? be ? adju sted ? externally ? by ? the ? sense ? resistor ? rs ? at ? cs ? pin. ? in? cv? control, ? multi \ mode ? operations ? are ? utilized ? to ? achieve ? high? performance ? and? high? efficiency. ? in? addition,? good ? load ? regulation ? is ? achieved ? by ? the ? built \ in ? cable ? drop ? compensation. ? device ? operates ? in ? pfm? in ? cc? mode ? as ? well? at ? larg e ? load ? condition ? and? it ? operates ? in ? pwm ? wi th ? frequency? reduction ? at ? light/medium ? load. ? ? rs2138? offers ? power ? on ? soft ? start ? control? and? protection ? coverage ? with ? auto \ recovery ? features ? including ? cycle \ by \ cycle ? current ? limiting, ? vdd? ovp, ? vdd? clamp ? and? uvlo. ? excellent ? emi ? performance ? is ? ac hieved ? with ? frequ ency ? jiggling. features ? applications ? 5% ? constant ? voltage? regulation, ? 5% ? constant ? current ? regulation ? at ? universal ? ac ? input ? primary \ side ? sensing ? and ? regulation ? without? 431 ? and? opto \ coupler ? power ? on ? soft \ start ? built \ in ? leading ? edge? blanking ? (leb) ? cycle \ by \ cycle ? current ? limiting ? vdd? under ? voltage ? lockout? with ? hysteresis ? (uvlo)? programmable ? cv? and? cc? re gulation ? adjustable ? constant ? current ? and ? output ? power ? setting ? built \ in ? secondary ? constant ? current ? control ? with ? primary ? side ? feedback ? built \ in ? adaptive ? current ? peak ? regulation ? built \ in ? primary ? winding ? inductance ? compensation ? program ? cable ? drop ? compensation ? vdd? ovp ? and? vdd? clamp ? available ? in ? an ? dip \ 8?packag e ? rohs ? compliant ? and? 100% ? lead ? (pb) \ free? and ? green ? (halogen ? free? with ? commercial ? standard) ? cell ? phone ? charger ? digital ? cameras ? charger ? small ? power ? adaptor ? auxiliary ? power ? for ? pc, ? tv? etc. ? linear ? regulator/rcc ? replacement ? ? ? fig.1. ? typical ?cc/cv ? curve ?
page ?no. ?: ? 2/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com ? this ? integrated ? circuit ? can ? be ? damaged ? by ? esd. ? orister ? corporation ? recommends ? that ? all ? integrated ? circuits ? be ? handled ? with ? appropriate ? precautions. ? failure ?to ? observe? proper ?handling ?and? installation ? procedures ? can ?cause ?damage. ? ? esd ? damage ? can ? range ? from ? subtle ? performance ? degradation ? to ? complete ? device? failure. ? precision ? integrated ? circuits ? may ? be ? more ? susceptible ?to ?damage ?becaus e ? very ?small ?parametric ?changes ? could ? cause ?the ? device ?not ?to ? meet ?its ?published ? specifications. ? application ? circuits ? gnd vout -+ d1 1 2 3 4 c1 c2 u1 rs2138 comp inv cs drain drain vcc gnd gnd r1 l1 c3 naux d2 r2 r3 r4 c4 r5 c5 d3 t1 d4 c6 r6 1 2 np ns ac in ? pin? assignments ? dip \ 8 ? ? ? ? package ? pin? symbol ? description ? 1? vdd? power ? supply ? 2? comp ? loop ? compensation ? for ? cv? stability ? 3? inv ? the ? voltage ? feedback ? from ? auxiliary ? winding. ? connected?to ? resistor ? divider ? from ? auxiliary ? winding ? reflecting ? output ? voltage. ? pwm ? duty ? cycle ? is ? determined ? by ? ea ? output ? and ? current ? sense? signal ? at ? pin ? 4. ? 4? cs ? current ? sense ? input ? 5,6? drain ? hv ? mosfet ? drain ? pin. ? the ? drain ? pin ? is ? connected ? to ? the ? primary ? lead ? of ? the ? transformer ? dip \ 8? 7, ? 8? gnd ? ground ? ordering ? information ? device ? device ? code ? rs2138 ? y? z ? y? is ? package ? & ? pin ? assignments ? designator ? : ? p: ? dip \ 8? z ? is ? lead ? free ? designator ? : ? p: ? commercial ? standard, ? lead ? (pb) ? free? and? phosphorous ? (p)? free? package ? g: ? green ? (halogen ? free? with ? commercial ? standard) ?
page ?no. ?: ? 3/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com block? diagram ? ? absolute ? maximum ? ratings ? symbol ? parameter? range? units? \? drain ? voltage ? (off ? state) ?\ 0.3v ? to ? bvdss ? v ? \? vdd ? voltage ?\ 0.3 ? to ? vdd_clamp ? v ? \? vdd ? zener ? clamp ? continuous ? current ? 10? ma ? \? comp ? voltage ?\ 0.3 ? to ? 7 ? v ? \? cs ? input ? voltage ?\ 0.3 ? to ? 7 ? v ? \? inv ? input ? voltage ?\ 0.3 ? to ? 7 ? v ? t j ? junction ? temperature ?\ 20? to ? 150 ? o c? t opr ? operating ? temperature ? range ?\ 20? to ? +85 ? o c? t stg ? storage ? temperature ? range ?\ 55? to ? 150 ? o c? t lead ? lead ? temperature ? (soldering, ? 10secs) ? 260 ? o c? note: ? stress? beyond ? those ? listed ? under ? ?absolute ? maximum ? ratings?? may ? cause ? permanent ? damage ? to ? the ? device. ? exposure ? to ? absolute ? maximum \ rated ? conditions ? for ? extended? periods ? may ? affect ? device ? reliability. ? output? power? table ? part ? no. ? package ? 230vac ? 15% ? 85? to? 265vac ? rs2138p ? dip \ 8 ? 20w ? 16w ?
page ?no. ?: ? 4/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com electrical ? characteristics ? (v dd =16v,? t a =25c, ? unless ? otherwise ? specified) ? symbol ? parameter ? test ? conditions ? min. ? typ. ? max. unit ? supply ? voltage ? (vdd) ? section ? i dd_st ? standby ? current ? vdd=13v?\ ? 5? 20? ua? i dd_op ? operation ? current ? operation ? supply ? current ? inv=2v,cs=0v, ? vdd=vddg=20v ? \? 2.5? 3.5? ma? uvlo(on) ? vdd? under ? voltage ? lockout? enter ? vdd? falling ? 7.5 ? 8.5 ? 10 ? v? uvlo(off) ? vdd? under ? voltage ? lockout? exit ? vdd? rising ? 13.5 ? 14.5 ? 16.0 ? v? ovp ? over ? voltage ? protection ? voltage ? ramp? up? vdd? until ? gate ? clock ? is ? off 27.5 ? 29.5 ? 31.5 ? v? v dd _clamp ? maximum ? vdd? opertation ? voltage ? i dd =10ma? 30.5 ? 32.5 ? 34.5 ? v? current ? sense ? input ? section ? t leb ? leb ? time ?\?\? 540 ?\? ns ? vth_oc ? over ? current ? threshold ?\? 870? 900? 930? mv ? td_oc ? ocp ? propagation ? delay?\ ? \ ? 150 ?\? ns ? z sense _in ? input ? impedance ?\?\? 50 ?\? k? tss ? soft ? start ? time ?\ ? \ ? 10 ?\? ms ? cv ? section ? freq_nom ? system ? nominal ? switch ? frequency?\ ?\ ? 60 ?\? khz? freq_startup?\ ? inv=0v, ? comp=5v?\ ? 14 ?\? khz? f/freq? frequency? jitter ? range ?\ ? \ ? +/ \ 4 ?\? % ? error ? amplifier ? section ? v ref _ea ? reference ? voltage ? for ? ea ?\? 1.97? 2? 2.03? v? gdc ? dc ? gain ? of ? the ? ea ?\?\? 60 ?\? db ? i_comp_max ? max. ? cable ? compensation ? current ? inv=2v, ? comp=0v ?\? 42 ?\? ua? power ? mosfet ? section ? bvdss ? mosfet ? drain \ source ? breakdown ? voltage \? \? 650 ?\? v? rds(on)? static? drain ? to ? source ? on ? resistance ?\?\? 3.0? 3.6 ?? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
page ?no. ?: ? 5/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com detail ? description ? rs2138 ? is ? a? cost ? effective? pwm ? power ? switch? optimized ? for ? off \ line ? low? power ? ac/dc ? applications? including ? battery ? chargers ? and ? adaptors. ? it ? operates ? in ? primary ? side? sensing ? and ? regulation, ? thus ? opto\ coupler ? and ? 431 ? are ? not ? required. ? proprietary ? built \ in ? cv ? and ? cc ? control ? can ? achieve? high ? precision ? cc/cv ? control ? meeting ? mos t ? adaptor ? an d ? charger ? application ? requirements. ? ? startup ? current ? and ? start ? up ? control ? startup ? current ? of ? rs2138 ? is ? designed ? to ? be ? very ? low ? so ? that ? vdd ? could ? be ? charged ? up ? above ? uvlo ? threshold ? and ? starts ? up ? quickly. ? a ? large? value? startup ? resistor ? can ? therefore ? be ? used ? to ? minimize? the ? power? loss ? in ? application. ? ? operating ? cur r ent ? the? operating ? current ? of ? rs2138 ? is ? as ? low? as ? 2.5ma. ? good ? efficiency ? is ? achieved ? with ? the ? low? operating ? current ? together ? with ? multi \ mode ? control ? features. ? ? soft ? start ? rs2138 ? features ? an ? internal ? soft ? start ? to ? minimize? the ? component ? electrical ? over \ stress ? during ? power ? on ? startup. ? as ? soon ? as ? vd d? reaches ? uvlo ? (o ff), ? the ? control ? algorithm ? will ? ramp ? peak ? current ? voltage? threshold ? gradually ? from ? nearly ? zero? to ? normal ? setting ? of ? 0.90v. ? every ? restart? is ? a ? soft ? start. ? ? cc/cv ? operation ? rs2138 ? is ? designed ? to ? produce ? good ? cc/cv ? control ? characteristic ? as ? shown ? in ? the ? fig. ? 1. ? ? in ? charger ? applications, ? a? dischar ged ? ba ttery ? charging ? starts ? in ? the ? cc ? portion ? of ? the ? curve ? until ? it ? is ? nearly ? full ? charged ? and ? smoothly ? switches ? to ? operate ? in ? cv ? portion ? of ? the ? curve. ? ? in ? an ? ac/dc ? adapter, ? the ? normal ? operation ? occurs? only ? on ? the ? cv ? portion ? of ? the ? curve. ? the? cc? portion ? provides ? output ? current ? limiting. ? in ? cv ? op e ration, ? the ? output ? voltage ? is ? regulated ? through ? the ? primary ? side? control. ? in ? cc? operation ? mode, ? rs2138 ? will ? regulate ? the ? output ? current ? constant ? regardless ? of ? the ? output? voltage ? drop. ? ? principle ? of ? operation ? to ? support ? rs2138 ? proprietary ? cc/cv ? control, ? system ? needs ? to ? be ? designed ? in ? dcm ? mode ? for? flyback ? system ? (r efer ? to ? typical ? application ? di agram). ? ? in ? the ? dcm ? flyback ? converter, ? the ? output? voltage ? can ? be ? sensed ? via ? the ? auxiliary ? winding. ? during ? mosfet ? turn \ on ? time, ? the ? load ? current ? is ? supplied ? from ? the ? output ? filter ? capacitor ? c o .? the ? current ? in ? the ? primary ? winding ? ramps? up. ? when ? mosfet ? turns ? off, ? the ? primary ? current ? transfers ? to ? the ? secondary ? at ? the ? amplitude ? of ? ? p s p s i n n i = ? ? the? auxiliary ? voltage ? reflects ? the ? output ? voltage ? as ? shown ? in ? fig.2 ? and ? it ? is ? given ? by ? ? )vv( n n v o s aux aux += ? ? where ? v ? indicates ? the ? drop ? voltage? of ? the ? output? diode. ? ?
page ?no. ?: ? 6/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com ? fig.2. ? auxiliary ? voltage ? waveform ? ? via ? a? resistor ? divider ? connected ? between ? the ? auxiliary ? winding ? and ? inv ? (pin ? 3), ? the ? auxiliary ? voltage? is ? sampled ? at ? the ? end ? of ? the ? demagnetization ? and ? it ? is ? hold ? until ? the ? next ? sampling. ? ? the? sampled ? voltage? is ? compared ? with ? v ref ? (2.0v) ? and ? the ? error ? is ? amplified.? the? error ? amplifier ? output? comp ? reflects ? the ? load ? condition ? and ? controls ? the ? pwm ? switching ? frequency ? to ? regulate ? the ? output? voltage, ? thus ? constant ? output ? voltage ? can ? be ? achieved. ? ? when ? sampled ? voltage? is ? below ? v ref ? and ? the ? error ? amplifier ? output ? comp ? reaches ? its ? maximum, ? the ? switching ? frequency ? is ? controlled ? by ? the ? sampled ? voltage? thus ? the ? output ? voltage ? to ? regulate ? the ? output ? current, ? thus ? the ? constant ? output ? current ? can ? be ? achieved.? ? adjustable ? cc? point ? and ? output ? power ? in ? rs2138, ? the ? cc? point ? and ? maximum ? output ? power? ca n? be ? externally ? ad justed ? by ? external ? current ? sense? resistor ? r s ? at? cs ? pin ? as ? illustrated ? in ? typical ? application ? diagram. ? the ? output ? power ? is ? adjusted ? through ? cc ? point ? change. ? the ? larger ? r s , ? the ? smaller? cc? point ? is, ? and ? the ? smaller ? output ? power ? becomes, ? and ? vice ? versa ? as ? shown ? in ? fig.3. ? ? ? fig.3. ? adjustable ? output ? power ? by ? changing ? r s ? ? operation ? switching ? frequency ? the? switching ? frequency ? of ? rs2138 ? is ? adaptively ? controlled ? according ? to ? the ? load ? conditions ? and ? the ? operation ? modes. ? no ? external ? frequency ? setting ? components ? are ? required. ? the ? operation ? switching ? frequency ? at? maximum? output? power ? is ? set ? to ? 60khz ? internally. ? ? for ? flyback ? operating ? in ? dcm, ? the? maximum? output ? power ? is ? given ? by ? 2 max pswp o ifl 2 1 p = ? where ? l p ? indicate? the ? inductance ? of ? primary ? winding ? and ? i p ? is ? the ? peak? current ? of ? primary ? winding. ? ?
page ?no. ?: ? 7/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com refer ? to ? the ? equation ? 3, ? the ? change ? of ? the ? primary ? winding ? inductance ? results ? in ? the ? change ? of ? the ? maximum ? output ? power ? and ? the ? constant ? output ? current ? in ? cc ? mode. ? to ? compensate ? the ? change ? from ? variations ? of ? primary ? winding ? inductance, ? the ? switching ? frequency ? is ? locked ? by ? an ? internal ? loop ? such ? that ? the ? switching ? freque nc y? is ? ? demag sw t2 1 f = ? ? since ? t demag ? is ? inversely ? proportional? to ? the ? inductance, ? as ? a? result, ? the ? product ? l p ? and ? f sw ? is ? constant, ? thus ? the ? maximum ? output? power ? and ? constant ? current ? in ? cc ? mode ? will ? not ? change ? as ? primary ? winding ? inductance ? changes. ? up ? to ? +/ \ 10% ? variation ? of ? the ? primary ? winding ? inductance ? can ? be ? compensated. ? ? frequency ? jiggling ? for ? emi ? improvement ? the? frequency ? jiggling ? (switching ? frequency ? modulation) ? is ? implemented ? in ? rs2138. ? the ? os cillation ? fre quency ? is ? modulated ? so ? that ? the ? tone ? energy ? is ? spread ? out. ? the ? spread ? spectrum ? minimizes ? the ? conduction ? band ? emi ? and ? therefore ? eases ? the ? system ? design. ? ? current ? sensing ? and ? leading ? edge ? blanking ? cycle \ by \ cycle ? current ? limiting ? is ? offered ? in ? rs2138 ? current ? mode ? pwm ? control. ? the ? switch ? current ? is ? detected ? by ? a ? sense ? resistor ? into? the ? cs ? pin. ? an? int e rnal ? leading ? edge ? blanking ? circuit ? chops ? off ? the ? sensed ? voltage ? spike? at ? initial ? internal ? power ? mosfet ? on ? state ? so ? that ? the ? external ? rc ? filtering ? on ? sense ? input ? is ? no ? longer ? needed. ? the? pwm ? duty ? cycle ? is ? determined ? by ? the ? current ? sense ? input ? voltage ? an d ? the ? ea ? output ? voltage. ? ? gate ? drive ? the? internal ? power? mosfet ? in ? rs2138 ? is ? driven ? by ? a? dedicated ? gate ? driver ? for ? power ? switch? control. ? too ? weak? the ? gate ? drive? strength ? results? in ? higher ? conduction ? and ? switch ? loss ? of ? mosfet ? while ? too ? strong ? gate ? drive ? compromises ? emi.? ? a ? good ? tradeo ff ? is ? achieved ? through ? th e ? built \ in ? totem ? pole ? gate ? design ? with ? right ? output ? strength ? control. ? ? programmable ? cable? drop ? compensation ? in ? rs2138, ? cable ? drop ? compensation ? is ? implemented ? to ? achieve ? good ? load ? regulation. ? an ? offset ? voltage ? is ? generated ? at? inv ? by ? an ? internal ? current ? flowing ? into ? the ? resister ? divider. ? the? current ? is ? inversely ? proportional ? to ? the ? voltage ? across? pin ? com p , ? as ? a? result, ? it ? is ? inversely ? proportional ? to ? the ? output ? load ? current, ? thus ? the ? drop ? due ? to ? the ? cable ? loss ? can? be ? compensated. ? as ? the ? load ? current ? decreases ? from ? full \ load ? to ? no \ load, ? the ? offset ? voltage? at ? inv ? will ? increase.? it ? can ? also ? be ? pro g rammed ? by ? adjusting ? the ? resistance ? of ? the ? divider? to ? compensate ? the ? drop ? for ? various ? cable ? lines? used. ? ? protection ? control ? good ? power ? supply ? system ? reliability ? is ? achieved ? with ? its ? rich ? protection ? features ? including ? cycle \ by \ cycle ? current ? limiting ? (ocp), ? vdd ? clamp, ? power ? on ? soft ? start, ? and ? under ? voltage ? locko u t ? on ? vdd(uvlo). ? ? vdd ? is ? supplied ? by ? transformer ? auxiliary ? winding ? output. ? the ? output ? of ? rs2138 ? is ? shut ? down ? when ? vdd ? drops ? below? uvlo ? (on) ? limit ? and ? switcher ? enters ? power ? on ? start \ up ? sequence ? thereafter. ? ? ? ? ? ? ? ? ? ?
page ?no. ?: ? 8/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com dip\ 8 ? dimension ? ? ? notes: ? a. all ? linear? dimensions ? are ? in ? inches? (millimeters). ? b. this ? drawing ? is ? subject ? to ? change ? without ? notice. ? c. falls ? within ? jedec ? ms \ 001. ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
page ?no. ?: ? 9/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com soldering ? methods ? for ? orister?s? products ? 1. ? storage ? environment: ? temperature=10 o c~35 o c? humidity=65%15% ? 2. ? reflow ? soldering ? of ? surface \ mount ? devices ? ? profile? feature ? sn \ pb ? eutectic ? assembly ? pb \ free ? assembly ? average ? ramp \ up ? rate ? (t l ? to ? t p ) ? <3 o c/sec ? <3 o c/sec ? preheat? \? temperature ? min ? (ts min ) ? \? temperature ? max ? (ts max ) ? \? time ? (min ? to ? max) ? (ts) ? ? 100 o c? 150 o c? 60~120 ? sec ? ? 150 o c? 200 o c? 60~180 ? sec ? tsmax? to ? t l ? ? \? ramp \ up ? rate ? ? <3 o c/sec ? ? <3 o c/sec ? time ? maintained ? above: ? \? temperature ? (t l ) ? \? time ? (t l ) ? ? 183 o c? 60~150 ? sec ? ? 217 o c? 60~150 ? sec ? peak ? temperature ? (t p ) ? 240 o c? +0/ \ 5 o c ? 260 o c? +0/ \ 5 o c ? time ? within ? 5 o c? of ? actual ? peak ? temperature ? (t p ) ? 10~30 ? sec ? 20~40 ? sec ? ramp \ down ? rate ? <6 o c/sec ? <6 o c/sec ? time ? 25 o c? to ? peak ? temperature ? <6 ? minutes? <8 ? minutes? 3. ? flow ? (wave) ? soldering ? (solder ? dipping) ? products ? peak ? temperature ? dipping ? time ? pb ? devices. ? 245 o c? 5 o c? 5sec ? 1sec ? pb \ free ? devices. ? 260 o c? +0/ \ 5 o c ? 5sec ? 1sec ? ? ? ? ? ? figure ? 1: ? temperature ? profile ? t p t l ramp-down ramp-up ts max ts min critical zone t l to t p t s preheat t l t p 25 t 25 o c to peak time temperature
page ?no. ?: ? 10/10 ds \ rs2138 \ 03??? september, ? 2009 ? www.orister.com ? ? important ? notice: ? ? ? ? orister ? corporation ? orister ? cannot ? assume ? responsibility ? for ? use ? of ? any ? circuitry ? other ? than ? circuitry ? entirely ? embodied ? in ? an ? orister ? product. ? no ? circuit ? patent ? licenses, ? copyrights, ? mask ? work ? rights, ? or ? other ? intellectual ? property ? rights ? are ? implied. ? ? orister ? reserves ? the ? right? to ? make ? changes ? to ? their ? products ? or ? specifications ? or ? to ? discontinue ? an y ? prod uct ? or ? service ? without ? notice. ? except ? as ? provided ? in ? orister?s ? terms ? and ? conditions ? of ? sale, ? orister ? assumes ? no ? liability ? whatsoever, ? and ? orister ? disclaims ? any ? express ? or ? implied ? warranty ? relating ? to ? the ? sale ? and/or ? use? of ? orister ? products ? including ? liability ? or ? warranties ? relating ? to ? fitness ? for ? a? particular ? purpose, ? merchantability, ? or ? infringement ? of ? any ? pa te nt, ? copyright ? or ? other ? intellectual? property ? right. ? in ? order ? to ? minimize ? risks ? associated ? with ? the ? customer?s ? applications, ? adequate ? design ? and ? operating ? safeguards ? must ? be ? provided ? by ? the ? customer ? to ? minimize? inherent ? or ? procedural ? hazards. ? testing ? and ? other ? quality ? control ? techniques ? are ? utilized ? to ? the ? extent ? orister ? deems ? necessary ? to ? su pp ort ? this ? warranty. ? specific ? testing ? of ? all? parameters ? of ? each ? device ? is ? not? necessarily ? performed. ?? ? orister ? and ? the ? orister ? logo ? are ? trademarks ? of ? orister ? corporation. ? all ? other ? brand ? and ? product ? names ? appearing ? in ? this ? document ? are ? registered ? trademarks ? or ? trademarks ? of ? their ? respective ? holders. ? ? ? ?
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