fe at ur e s ? pfm con t rol a s ynchron o u s booster ? up to 86% ef ficiency ? quiescen t su pply current: 4.5a ? zero shutdown current ? output voltag e accuracy: 1% ? fixed output voltage ? provides 20m a from single aaa cell ? input voltag e rang e: 0.8 v to 5 . 5v ? startup voltage : 0.9v ? 6l sot-26 p a ckage applications ? cellular and c o rdless phon es ? wirele ss lan cards ? palmtop c o m p uters ? personal c o m m unication equipment ? pen drives ? bluetooth dev i ces ? des c ription the PIC9310 compact, hi gh-efficiency, step-up dc- dc converte rs are av ail a ble in tiny, 6-pin thin sot26 pack ages. they fe ature an ext r emely low 5a quiescen t supply current to ensur e the highest possible light-load effic iency. optimized for operati o n from one to t w o alkaline or nickel-met al- hydride (nimh) cells, or a single li+ cell, these devices are i d eal for application s w h er e extr emely low quiescent current an d ultr a- sm all size ar e critical. the PIC9310 al so feature proprietary n o ise- reduction circuitry , which suppre s se s electrom agne tic interferen ce (emi) c a u s ed by the inductor in many step -u p application s . th e family offers differ e nt combin at ions of fi xed outputs, shutdown, and emi reducti o n (see selector guide). its unique d e sign is optimi zed for high efficiency at light load con d ition. typical application circuit async boost with 600khz s w itching PIC9310 ww w. pic s emi. c o m road- 8 , house- 2 / a, b a ri dhar a di pl omati c area , dhaka- 1212, p h one: +880- 2- 8861 966, f a x: +880- 2- 8835244 1
PIC9310 asy nc boost with 600khz switchin g el ectrical characteristics (typical v a lu es are at t a = +25 c. v batt = 1.2v, v ou t = 3.3v, v ou t = v ou t ( n o m ) , shdn = out , r l = , unless otherwi s e n o t e d.) p a r a m e t e r symbo l co nditio n s m i n t y p m a x u n i t operating input voltage v in ( note 1 ) 5.5 v output voltage variation v out 3 . 2 2 4 3 . 3 0 7 3 . 3 8 9 v minimum start u p input vo l t age i out =1ma, v in :0 -> 2v 0 . 8 6 0 . 9 2 v hold on v o ltag e i out =1ma, v in :0 -> 2v 0.7 v no lo ad input current i out =0ma 10 a n- channel on-resistance r ds ( o n) measured from sw pin voltage and inductor current during sw o n time 1 . 4 ? maximum oscillating freq f osc v out forced = v out (nom) * 0.95 7 5 1 0 7 1 4 0 k h z duty ratio d max v out forced = v out (nom) * 0.95 70 77 85 % e f f i c i e n c y e f f 8 6 % quiescent current into out (no switching) v in = v out +0.5 v (v out pin) (notes 2, 3) 4.5 a quiescent current into out v out forced = v out (nom) * 0.95 13 a switch leakage vsw=5.5v,vin = vout + 0.5v 1 na v il 1 . 2 shdn voltage threshold v ih 0 . 4 mv shdn input bi as current v shd n = 5.5v 1 . 1 n a lbi voltage threshold v out forced = v out (nom)*1.05 6 4 5 6 7 0 7 0 0 mv lb i input hyste r esis v out forced = v out (nom)*1.05 18 mv lb i input curre nt v out forced = v out (nom)*1.05 0 . 0 2 na lb o o u tput lo w vo ltage force 20ma into lbo 0.5 0.6 v note 1: guar anteed with th e addition of a schottky mbr0 520l external diode between lx and out w h en using the PIC9310 with only one cell, a n d assumes a 0. 3v voltage drop across the schottky diode. note 2: supply current is me asured with an ammeter between th e output and out pin. this current correlates directl y with actual battery supply current, but is reduced in value according to th e step -up ratio and efficiency. note 3: v out fo rced to the fo llowing co nditio ns to inhibit switching: v out = 1.05 * v out( nom) , v out = 3.307v. ww w. pic s emi. c o m road- 8 , house- 2 / a, b a ri dhar a di pl omati c area , dhaka- 1212, p h one: +880- 2- 8861 966, f a x: +880- 2- 8835244 2
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