general description the MAX8680 highly efficient complete power-supply solution is designed for digital still cameras (dscs) and digital video cameras (dvcs). the device integrates seven on-chip power mosfet dc-dc converters with up to 95% efficiency to power all critical power supplies in dsc systems. each converter also features true shutdown , as well as internal compensation to mini- mize external component count. the seven dc-dc converter outputs are: step-up synchronous-rectified dc-dc converter (su). the MAX8680 is bootstrapped from v su . main synchronous-rectified step-down dc-dc con- verter (m) for dsp i/o supply voltage. ddrz synchronous-rectified step-down dc-dc converter (z) for dsp ddr supply voltage. low-voltage (down to 1v) synchronous-rectified step-down dc-dc converter (sd) for dsp core sup- ply voltage. high-voltage, step-up dc-dc converter with current regulation and pwm dimming control (ledbst) for white leds (wled). high-voltage step-up dc-dc converter (ccdbst) for ccd imagers or positive lcd bias supplies. transformerless inverting dc-dc converter (ccdinv) for ccd imagers or negative lcd bias supplies. the MAX8680 has an independent/simultaneous power-on sequence of the ccdbst and ccdinv con- verters. for a preset power-on sequence of ccdbst before ccdinv, contact the factory. the MAX8680 operates with 1-cell lithium-ion (li+) bat- tery, two-aa cell, or dual-battery designs and is avail- able in a 5mm x 5mm, 40-pin thin qfn package. the MAX8680 operates over the -40? to +85? extended temperature range. applications dscs and dvcs pdas and portable media players gps navigation systems features ? 95% efficient synchronous-rectified dc-dc converters ? 90% efficient boost-buck operation ? 85% efficient dc-dc converters for ccd, lcd, wled, and/or oled ? internal compensation on all channels ? true shutdown on all step-up converters ? overload protection ? soft-start for controlled startup current ? dropout operation (100% duty cycle) on step- down converters ? regulated current output for up to 6 white leds ? pwm dimming of wled current ? adjustable led overvoltage protection up to 27v ? transformerless inverting converter for ccd ? 2mhz switching frequency for low-voltage channels ? 2.5% switching frequency accuracy ? 1a shutdown supply current ? power-on voltage tracking for core and main outputs ? all internal power mosfets ? sdok power-ok indicator MAX8680 smallest, all-internal mosfet, 7-channel dsc pmic in tiny 5mm x 5mm thin qfn ________________________________________________________________ maxim integrated products 1 batt su step-up onsu main step-down ddrz step-down ledbst ccdbst ccdinv onm onsd onled onbst oninv onz sd step-down v su 5v v main 3.3v v sd 1.8v v ddrz 2.5v v ledbst up to 6 wleds v ccdbst +15v v ccdinv -7.5v input 2.7v to 5.5v sdok MAX8680 typical operating circuit 19-0681; rev 2; 11/07 pin configuration appears at the end of data sheet. for pricing, delivery, and ordering information, please contact maxim direct at 1-888-629-4642, or visit maxim's website at www.maxim-ic.com. evaluation kit available ordering information part temp range pin-package pkg code MAX8680etl+ -40 c to +85 c 40 thin qfn-ep* 5mm x 5mm x 0.8mm t4055-2 + denotes a lead-free package. * ep= exposed paddle. true shutdown is a trademark of maxim integrated products, inc. abridged
MAX8680 smallest, all-internal mosfet, 7-channel dsc pmic in tiny 5mm x 5mm thin qfn 14 ______________________________________________________________________________________ batt lxsu pvsu su fbsu pgsu (ep) pgsu (ep) pgsd (ep) pgm (ep) lxm v su v su (5v, 500ma) pvm fbm v main (3.3v, 300ma) pvsd lxsd fbsd onsu onm onled onbst oninv lxinv fbinv swbst lxbst fbbst pvled swled lxled ovled fbled pgbst (ep) pgled (ep) ep gnd ref pvinv v batt or v su v batt (2v to 5.5v) v ccdbst (15v, 30ma) v ledbst (16v, 30ma) v ccdinv (-7.5v, 100ma) onsd pvbst c20 0.1 f c18 1 f l2 4.7 h c1 22 f c2 22 f l1 2 h l6 4.7 h l7 4.7 h d1 d2 d3 c5 1 f 24 33 32 30 26 27 38 39 1 35 5 34 28 40 6 10 21 7 25 8 9 11, 12 14 13 18 22 19, 20 17 23 15 16 29 lxsu 31 pvsu 37 lxz 4 r16 100k v batt onz 2 pgz (ep) fbz 3 pvz 36 d4 d5 d6 d7 MAX8680 c3 22 f c4 22 f c16 0.1 f r17 100 r2 100k r3 232k r1 402k c6 10 f c7 10 f v batt c8 10 f v batt or v su c11 1 f v batt c14 1 f v batt v ref c16 1 f r4 100k v sd (1.8v, 250ma) l3 4.7 h r5 80k c10 10 f c9 10 f r6 100k v ddrz (2.5v, 200ma) l4 4.7 h l5 4.7 h r7 150k c12 10 f c13 10 f c15 1 f r8 100k r9 1.6m r10 100k c17 1 f c19 4.7 f r11 1.4m r12 100k r13 604k r14 100k sdok r15 10 figure 1. MAX8680 typical application circuit (for li+ cell design, connect pvz and pvinv to batt; for two-aa or dual-battery design, connect pvz and pvinv to pvsu) note: all converters?power ground connections are through the exposed paddle (ep). abridged
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