advanced power electronics corp. features description input voltage 3v to 20v output voltage 3.3v to 32v 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. data and specifications subject to change without notice 201010182 APE1911 package & ordering information step-up pwm dc/dc converter 1 typical application the APE1911 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 APE1911 can be operated at switching frequencies of 500 khz allowing for easy filtering and low 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. v out = v fb x (1+r4/r3) , v fb = 1.0v, r3 = 1k ~3k ? vcc=5v r4 11k c2 0.47uf c1 470uf d1 b340a c4 470uf l1 22uh vout=12v u1 APE1911 6 2 4 1 3 8 7 5 sw vcc ss en fb sgnd pgnd sw c7 0.1uf c3 option r3 1k r1 100k 0.47uf c8 c5 4.7uf package type mp : esop-8 APE1911x (top view ) 1 2 3 4 8 7 6 5 ss fb esop-8 en v cc sgnd pgnd sw sw exposed pad (ep is connect to sw)
advanced power electronics corp. APE1911 absolute maximum ratings vcc pin voltage (v cc ) ----------------------------------- - gnd - 0.3v to gnd + 22v 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 34v 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 =5v, v out =12v, t a =25 c, unless otherwise specified) parameter sym test condition min typ max units operating supply voltage v cc 3 - 20 v output voltage range v out 3.3 - 32 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*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 2.8 3 - a v cc =5v - 40 80 v cc =12v - 30 60 efficiency effi v cc =5v, v out =12v, i out =0.5a - 92 - % maximum duty cycle dc max v fb =0v - 85 - minimum duty cycle dc min v fb =1.5v - 0 - thermal shutdown temp tsd - 145 - c 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 r dson
advanced power electronics corp. APE1911 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 here 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
advanced power electronics corp. APE1911 function description pwm control setting the output voltage table 1 resistor select for output voltage setting inductor selection input capacitor selection 4 the APE1911 consists of dc/dc converters that employ a pulse-width modulation (pwm) system. in converters of the APE1911, 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 APE1911 adjustable output version. the external resistor sets the output voltage according to the following equation: for most designs, low inductance values are physically smaller but require faster switching, which results in some efficiency loss. the inductor value can be derived from the following equation: v out = 1.0v x (1+r4/r3) l = [v in x (v out -v in )] / v out x ? i l x f lx where is inductor ripple current. large value inductors lower ripple current and small value inductors result in high ripple currents. choose inductor ripple current approximately 15% of the maximum input current 2.4a, ? i l =0.18a. the dc current rating of the inductor should be at least equal to the maximum load current plus half the ripple current to prevent core saturation (2.4a+0.18a). 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. v out 9v 12v 15v 18v l1 value 18uh 22uh 25uh 33uh v out r3 r4 12v 1k 11k 15v1.3k18k 18v1.3k22k 24v1.3k30k 32v2.2k68k
advanced power electronics corp. APE1911 function description output capacitor selection output capacitor selection 5 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. when laying out the pc board, the following suggestions should be taken to ensure proper operation of the APE1911. 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 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. (APE1911 pcb layout -top view)
advanced power electronics corp. APE1911 typical performance characteristics 6 11 11.2 11.4 11.6 11.8 12 12.2 12.4 12.6 12.8 13 345678910 vcc (v) vout (v) vcc vs vout iout=0.1a 11 11.2 11.4 11.6 11.8 12 12.2 12.4 12.6 12.8 13 0 100 200 300 400 500 600 iout (ma) vout (v) iout vs vout vcc=5v 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 369121518 vcc (v) current limit (a) vcc vs current limit vout=24v 0.0 1.0 2.0 3.0 4.0 5.0 6.0 -50 -25 0 25 50 75 100 temperature () current limit (a) temperature vs curret limit vcc=5v, vout=12v 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. APE1911 typical performance characteristics 7 (v cc =5v, vout=12v, load=0.8a, ss=0.47uf) power-on wave enable-on wave (v cc =5v, vout=12v, load=0.8a, ss=0.47uf) v cc ss v out i sw v en ss v out i sw
advanced power electronics corp. marking information esop-8 APE1911 8 1911mp ywwsss part number date code (ywwsss) y ? last digit of the year ww ? week sss ? sequence package code
package outlines detail a l h e a a2 a1 e d 7 (4x) b y c detail a y x expose pad dimensions in millimeters dimensions in inches symbol min. nom. max. min. nom. max. a - - 1.75 - - 0.069 a1 0 - 0.15 0 - 0.06 a2 1.25 - - 0.049 - - c 0.1 0.2 0.25 0.0075 0.008 0.01 d 4.7 4.9 5.1 0.185 0.193 0.2 e 3.7 3.9 4.1 0.146 0.154 0.161 h 5.8 6 6.2 0.228 0.236 0.244 l 0.4 - 1.27 0.015 - 0.05 b 0.31 0.41 0.51 0.012 0.016 0.02 e 1.27 bsc 0.050 bsc y - - 0.1 - - 0.004 x - 2.34 - - 0.092 - y - 2.34 - - 0.092 - 0 o - 8 o 0 o - 8 o mold flash shall not exceed 0.25mm per side jedec outline: ms-012 ba advanced power electronics corp. APE1911
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