AP1621 pwm/pfm dual mode step -down dc/dc controller this datasheet contains new product information. anachip corp. reserves the rights to modify the product specification without notice. no liability is assumed as a result of the use of this product. no rights under any patent accompany the sale of the product. rev.1.2 dec. 23, 2004 1/5 ? features - input voltage range:2.2v~7v v out type - adjustable version 2.5% - oscillator freq uency: 300khz 20% - high efficiency: 92% typ . - stand-by capability: i stb 2a. max . - output voltage type possible fb - package: sot23-5 ? applications electronic information organizers palmtops cellular and portable phones portable audio systems various multi-function power supplies ? general descriptions the AP1621 series are multi-functional step-down dc/dc converters with built-in speed, low on resistance drivers. a more than 1a output current is possible using an externally connected transistor, coil, diode and capacitor. output voltage is set-up by external resistor. 2.5% accuracy . with a 300khz switching frequency, the size of the external components can be reduced. control switches from pwm to pfm during light loads with the AP1621 pwm/pfm switchable and the series is highly efficient from light loads to large output currents. during stand-by time ce pin ?low? ,current consumption is reduced to less than 2a. with u.v.l.o internal, the external mosfet. will be forcibly switched off if used below the stipulated voltage. ? pin assignment 1 3 2 5 4 ce v out v dd gnd fb AP1621a 1 3 2 5 4 ce v out v dd gnd sot23-5 fb (top view) AP1621b ? pin descriptions pin no. a b pin name function 14v out external pmosfet connection 2 2 gnd ground 35 v dd power supply 41 ce chip enable: h: enable l: disable 5 3 fb feedback pin
AP1621 pwm/pfm dual mode step-d own dc/dc controller anachip corp. www.anachip.com.tw rev. 1.2 de c 23, 2004 2/5 ? ordering information AP1621x x x x x w : sot23-5 packing a : taping package lead free blank : normal l : lead free package version a : a version b : b version blank: adjustable -33: 3.3v vout ? block diagrams phase compensation vref with ce + - pwm/pfm controller + - ramp wave generator, osc buffer, driver v out ce gnd v dd pwm comparator fb ? absolute maximum ratings ta=25c parameter symbol rating unit v in pin voltage v dd -0.3 ~ 8 v v out pin voltage v out -0.3 ~ v in +0.3 v fb pin voltage v fb -0.3 ~ v in +0.3 v ce pin voltage v ce -0.3 ~ v in +0.3 v v out pin current v out 100 ma continuous total power dissipation pd 250 mw operating ambient temperature topr -30 ~ +80 c storage temperature tstg -40 ~ +125 c
AP1621 pwm/pfm dual mode step-d own dc/dc controller anachip corp. www.anachip.com.tw rev. 1.2 de c 23, 2004 3/5 ? electrical characteristics AP1621 v out 3.3v, f osc 300khz ta=25c parameter symbol conditions min. typ. max. unit fb voltage v fb 1.1625 1.2 1.2375 v output voltage v out AP1621-33 only 3.2 3.3 3.4 v maximum input voltage v in 7 - - v uvlo voltage min. operating voltage v uvlo same as i dd , voltage required to maintain h at v out - - 2.2 v supply current i dd no external components, ce=v in , v out =0v - 35 102 a stand-by current i stb no external components, ce=v in , v out =0v - - 2 a oscillator frequency fosc measuring of ext/waveform, v in =output voltage+0.3v 240 300 360 khz maximum duty ratio maxdty 100 - - % pfm duty ratio pfmdty no load (AP1621 only) 15 25 35 % ce ?high? voltage v ceh no external components, v fb =0v, apply 0.65v (min.) to ce, determine v out ?low? 0.65 - - *vcc ce ?low? voltage v cel same as v ceh , determine ext/?high? - - 0.20 *vcc efficiency effi - 92 - % measuring conditions: unless otherwise specified, connect external components. v in =5.0v,l out =220ma series amendment: AP1621 external components: c ce 0.1 f, r ce 100k ?
AP1621 pwm/pfm dual mode step-d own dc/dc controller anachip corp. www.anachip.com.tw rev. 1.2 de c 23, 2004 4/5 ? typical application circuit (1) AP1621-adj + - c fb r a r b d1 out v ss fb v cc r vcc c vcc AP1621 =~200k pmos v out l ce r ce c ce ) r r (1 vref vo b a + = 100k 0.1uf (2) AP1621-33 only + - d1 out v ss fb v cc r vcc c vcc ce AP1621 pmos v out r ce c ce l 100k 0.1uf ? marking information xx : identification code (see appendix) y : year: 0-9 m : month: a~l x : blank: normal l: lead free package sot23-5l xx y m x 7 12 3 4 5 appendix part number output version AP1621a AP1621b adj ex eu 3.3v ez et
AP1621 pwm/pfm dual mode step-d own dc/dc controller anachip corp. www.anachip.com.tw rev. 1.2 de c 23, 2004 5/5 ? package information package type: sot23-5l gauge plane 0.25 mm l l1 e1 e e1 d 123 4 5 b e b1 b c c1 base metal with plating a2 a1 a seating plane 0.10 c 5x 2(4x) 1(4x) dimensions in millimeters dimensions in inches symbol min. nom. max. min. nom. max. a 1.05 1.20 1.35 0.041 0.047 0.053 a1 0.05 0.10 0.15 0.002 0.004 0.006 a2 1.00 1.10 1.20 0.039 0.043 0.047 b 0.25 - 0.55 0.010 - 0.022 b1 0.25 0.40 0.45 0.010 0.016 0.018 c 0.08 - 0.20 0.003 - 0.008 c1 0.08 0.11 0.15 0.003 0.004 0.006 d 2.70 2.85 3.00 0.106 0.112 0.118 e 2.60 2.80 3.00 0.102 0.110 0.118 e1 1.50 1.60 1.70 0.059 0.063 0.067 l 0.35 0.45 0.55 0.014 0.018 0.022 l1 0.60 ref. 0.024 ref. e 0.95 bsc. 0.037 bsc. e1 1.90 bsc. 0.075 bsc. 0 o 5 o 10 o 0 o 5 o 10 o 1 3 o 5 o 7 o 3 o 5 o 7 o 2 6 o 8 o 10 o 6 o 8 o 10 o
|
