advanced power electronics corp. features description input voltage 3v to 13v output voltage 3.3v to 20v duty ratio 0% to 85% pwm control oscillation frequency 500khz. enable and thermal shutdown function. internal current limit. built-in n-channel mosfet esop-8 & pb-free package. halogen free product data and specifications subject to change without notice typical application 20130222v1.1 APE1912 step-up pwm dc/dc converte r 1 the APE1912 is high efficient step-up dc/dc converter. large output current is possible having a built in internal n channel mosfet, and using an external coil and diode. the APE1912 can be operated at switching frequencies of 500 khz allowing for easy filtering and lo w noise, the size of the external components can be reduced. output voltage is programmable with 1.0v of standard voltage supply internal, and using externally connected components, output voltage (fb) can be set up at will. the soft-start time can be programmed by outside capacitor; the function prevents overshoot at startup. build inside current limit, thermal shutdown and enable functions. vcc= 3.0 ~ 4.5 v r4 12k c2 0. 47 uf d1 b540a c4 220 uf l1 2.2uh vout =5 v u1 ape 1912 sw vcc ss en fb sgnd nc pgnd c1 10 uf c3 0. 1uf r3 3k r1 100k 0. 47 uf c8 c5 22 uf c7 r5 470r 0. 1 uf v out < 8v, v out = v fb x (1+r4/r3) , v fb = 1.0v, r3 = 1k 20m < cout esr < 80m
advanced power electronics corp. APE1912 absolute maximum ratings vcc pin voltage (v cc ) ----------------------------------- gnd - 0.3v to gnd + 14v feedback pin voltage (v fb ) ---------------------------- - gnd - 0.3v to 6v on/off pin voltage (v en ) ------------------------------ - gnd - 0.3v to vcc switch pin voltage (v sw ) -------------------------------- - gnd - 0.3v to 22v ss pin voltage (v ss ) ------------------------------------- - gnd - 0.3v to 6v power dissipation (p d ) ----------------------------------- internally limited storage temperature range (t st ) ------------------- - -40c to +150c operating junction temperature (t opj ) ------------- - -20c to +125c thermal resistance from junction to case(rth jc ) 15c/w 40c/w note. rth ja is measured with the pcb copper area (connect to exposed pad) of approximately 1 in 2 (multi-layer). electrical specifications (v in =3.3v, v out =5v, t a =25 o c, unless otherwise specified) parameter sym test condition min typ max units operating supply voltage v cc 3 - 13 v output voltage range v out 3.3 - 20 v feedback voltage v fb i out =0.1a 0.98 1 1.02 v feedback bias current i fb i out =0.1a - 0.1 0.5 ua quiescent current i ccq v fb =1.5v force driver off - 4 6 ma shutdown supply current i sd v en =0v - 1 10 ua oscillation frequency f osc sw pin 400 500 600 khz line regulation v cc =3~0.8 x vout - 1 - % load regulation i out =50m~1a - 1 - % v sh high (regulator on) 2 - - v sl low (regulator off) - - 0.8 i sh v en =2.5v (on) - 20 - ua i sl v en =0.3v (off) - -1 - ua ss pin current i ss -8-ua switching current limit i lim-sw 56- a v cc =5v - 25 - v cc =3.3v - 35 - efficiency effi v cc =3v, v out =5v, i out =0.5a - 90 - % maximum duty cycle dc max v fb =0v - 85 - minimum duty cycle dc min v fb =1.5v - 0 - thermal shutdown temp tsd - 145 - o c r dson 2 thermal resistance from junction to ambient(rth ja ) en pin input current v en pin logic input threshold voltage m % internal mosfet r dson
advanced power electronics corp. APE1912 package & ordering information pin descriptions pin symbol pin descripiton vcc sw fb h : normal operation ss soft-start pin. pgnd power ground pin sgnd block diagram en 3 ic power supply pin switch pin. connect external inductor & diode her e feedback pin l : shutdown signal ground pin. shutdown pin phase compensation + - pwm controller + - oscillator buffer driver fb en pgnd sw vcc thermal shutdown vref=1.0v 0.06v 8ua ss regulator v en sgnd package type mp : esop-8 APE1912x ( top view ) 1 2 3 4 8 7 6 5 ss fb esop-8 en v cc sgnd nc pgnd sw exposed pad (ep is connect to sw)
advanced power electronics corp. APE1912 function description pwm control setting the output voltage table 1 resistor select for output voltage setting input capacitor selection function description output capacitor selection 4 the APE1912 consists of dc/dc converters that employ a pulse-width modulation (pwm) system. in converters of the APE1912, the pulse width varies in a range from 0 to 85%, according to the load current. the ripple voltage produced by the switching can easily be removed through a filter because the switching frequency remains constant. therefore, these converters provide a low-ripple power over broad ranges of input voltage and load current. application circuit item shows the basic application circuit with APE1912 adjustable output version. the external resistor sets the output voltage according to the following equation: v out = 1.0v x (1+r4/r3) v out r3 r4 5v 3k 12k 12v 1k 11k 15v1.3k18k the input capacitor reduces the surge current drawn from the input and switching noise from the device. the input capacitor impedance at the switching frequency shall be less than input source impedance to prevent high frequency switching current passing to the input. a low esr input capacitor sized for maximum rms current must be used. the capacitor voltage rating should be at least 1.5 times greater than the input voltage, and often much higher voltage ratings are needed to satisfy. the output capacitor is required to keep the output voltage ripple small and to ensure regulation loop stability. the output capacitor must have low impedance at the switching frequency. a low esr capacitor sized for maximum rms current must be used. the low esr requirements needed for low output ripple voltage. the capacitor voltage rating should be at least 1.5 times greater than the input voltage, and often much higher voltage ratings are needed to satisfy.
advanced power electronics corp. APE1912 function description output capacitor selection 5 when laying out the pc board, the following suggestions should be taken to ensure proper operation of the APE1912. these items are also illustrated graphically in below. 1. the power traces, including the source trace, the schottky and the c1 trace should be kept short, direct and wide to allow large current flow. 2. the power ground & r fb ground is keep c4 ? s ground closed and far away signal ground. 3. the signal ground trance is distant from power ground trance. 4. the exposed pad is connecting to sw trace closely and widely. (reduce ic temperature) 5. do not trace signal line under inductor.
advanced power electronics corp. APE1912 typical performance characteristics 6 250 300 350 400 450 500 550 600 650 700 750 -50-250 255075100 temperature () frequency (khz) temperature vs frequency vcc=5v, vout=12v iout=100ma 0.95 0.96 0.97 0.98 0.99 1.00 1.01 1.02 1.03 1.04 1.05 -50 -25 0 25 50 75 100 temperature () vfb (v) temperature vs vfb
advanced power electronics corp. marking information esop-8 APE1912 7 1912mp ywwsss part numbe r date code (ywwsss) y last digit of the year ww week sss sequence package code
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