1 / 7 MA5604 major power technology co., ltd. rev. 1.0 jun . 04 , 201 4 38 v 5 a synchronous buck converter ? general description the ma560 4 is a monolithic synchronous buck regulator. the device integrates internal high side and external low side power mosfets, and provides 5a of continuous load current over a wide input voltage of 8 v to 38 v. current mode control provides fast transient response and cycle - b y - cycle current limit. an internal soft - start prevents inrush current at turn - on, this device, available in so p 8l - ep ( exposed pad) package, provides a very compact solution wi th minimal external components. ? features - wide 8 v to 38 v operating input range - integrated 9 0m high side power mosfet switches - output adjustable from vfb ( 1 v) to 20v - up to 9 5 % efficiency - internal soft - start - stable with low esr ceramic output capacitors - fixe d 16 0khz frequency - cycle - by - cycle over current protection - input under /over voltage lockout ? application circuit in en vdd lg bs sw fb comp input c 7 10 f 50 v r 4 100 k c 5 100 nf l 1 33 h r 1 40 k r 2 10 k c 8 22 f 10 v output 5 v 5 a c 3 r 3 c 4 0 . 1 f c 6 0 . 1 f ma 5604 r 5 0 3 . 3 nf 15 k pad ( gnd ) c 2 470 f 10 v q 1 nmos c 1 220 f 50 v v out =v fb (1+ r1/r2 ) , v fb = 1 .00 v, r2 suggest 10k~30k
2 / 7 MA5604 major power technology co., ltd. rev. 1.0 jun . 04 , 201 4 ? pin assignment the package of ma560 4 is so p8l - ep(exposed pad) ; the pin assignment is given by : name description bs boot - strap pin. supply high side gate driver. decouple this pin to lx pin with 0.1uf ceramic cap. in power input pin . bypass i n to gnd with a suitably large capacitor to eliminate noise on the input to the ic. sw power switching output. sw is the switching node that supplies power to the output. connect the output lc filter from sw to the output load. lg gate drive for extern al low side n - mosfet. . pad ground ( connect to gnd) . fb feedback input. fb senses the output voltage to regulate that voltage. drive fb with a resistive voltage divider from the output voltage. comp compensation node. comp is used to compensate the regu lation control loop. connect a series rc network from comp to gnd to compensate the regulation control loop. en enable control. pull high to turn on. do not float. vdd internal regulator pin ? o rder/marking information order information top marking (so p - 8l)
3 / 7 MA5604 major power technology co., ltd. rev. 1.0 jun . 04 , 201 4 ? b lock d iagram ? a bsolute maximum ratings ( at t a =25 c ) characteristics symbol rating unit supply voltage v in C 0.3 to + 4 2 v switch node voltage v sw C 0.3 to v in + 0.3 v boost voltage v bs vsw C 0.3 to vsw + 6 v all other pins C 0.3 to +6 v lead temperature 260 c storage temperature C 65 to +150 c junction temperature t j 150 c output voltage v out vfb to 20 v ambient operating temperature C 40 to +8 5 c thermal resistance from junction to case jc 15 c/w thermal resistance from junction to ambient ja 40 c/w note : ja is measured with the pcb copper area of approximately 1 in 2 ( multi - layer). that need connect to exposed pad.
4 / 7 MA5604 major power technology co., ltd. rev. 1.0 jun . 04 , 201 4 ? e lectrical c h aracteristics ( v in = 12v, t a = +25c, unless otherwise noted. ) characteristics symbol conditions min typ max units input voltage range 8 - 38 v shutdown supply current i sd v en = 0v - 0.7 1. 3 ma quiescent current i ccq v en = 5 .0v; v fb = 1.0 5 v - 0.7 1.5 ma feedback voltage v fb 8 v v in 38v 0.9 8 1 . 00 1.02 v feedback overvoltage threshold ovp ( fb) - 1.1x - v fb high - side switch on resistance ( note ) r ds(on)1 - 90 - m high - side switch leakage current v en = 0v, v sw = 0v - - 10 a high - side switch current limit minimum duty cycl e 5 . 1 6 . 0 - a l g rise time t lxr c lx =1000pf - 4 0 - n s l g fall time t lxf c lx =1000pf - 4 0 - ns lg driver bias supply voltage - 5 - v oscillation frequency f osc1 - 16 0 - khz short circuit oscillation frequency f osc2 v fb = < 0 .5 v - 6 0 - khz maximum dut y cycle d max - 90 - % minimum on time ( note ) t on(min) - 220 - ns en lockout threshold voltage enh ( lock) - 2.5 - v en lockout hysterisis - 210 - mv input under voltage lockout threshold uvlo v in rising 6.5 7. 0 7.5 v input under voltage lockout thr eshold hysteresis uvlo - hys - 80 0 - mv input ov er voltage lockout threshold ovlo v in rising - 40 - v input ov er voltage lockout threshold hysteresis ovlo - hys - 5 - v soft - start period - 3 - ms thermal shutdown t sd - 1 5 0 - c thermal shutdown hyste risis t sh - 30 - c note : guaranteed by design.
5 / 7 MA5604 major power technology co., ltd. rev. 1.0 jun . 04 , 201 4 ? function descriptions the ma560 4 is a synchronous rectified, current - mode, step - down regulator. it regulates input voltages from 8 v to 38 v down to an output voltage as low as v fb , and supplies up to 5a of load current. the ma560 4 uses current - mode control to regulate the output voltage. the output voltage is measured at fb through a resistive voltage divider and amplified through the internal tran conductance error amplifier. the voltage at the comp pin is compared to the switch current measured internally to control the output voltage. the converter uses internal n - channel mosfet switches to step - down the input voltage to the regulated output voltage. since the high side mosfet requires a gate voltage gr eater than the input voltage, a boost capacitor connected between sw and bs is needed to drive the high side gate. the boost capacitor is charged from the internal 5v rail when sw is low. when the ma560 4 fb pin exceeds 1 0% of the nomi nal regulation voltage of v fb , the over voltage comparator is tripped and the comp pin is discharged to gnd, forcing the high - side switch off. ? application information component selection setting the output voltage the output voltage is set using a resistive voltage divider from the output voltage to fb pin. the voltage divider divides the output voltage down to th e feedback voltage by the ratio . thus the output voltage is: v out = v fb 2 2 1 r r r ? for example, v fb =1.00v for a 5.0 v output voltage, r2 is 10k, and r1 is 40 k. inductor selection the inductor is required to supply constant current to the output load while being driven by the switched input voltage. a larger value inductor will result in less ripple current that will result in lower output rippl e voltage. however, the larger value inductor will have a larger physical size, higher series resistance, and/or lower saturation current. a good rule for determining the inductance to use is to allow the peak - to - peak ripple current in the inductor to be a pproximately 30% of the maximum switch current limit. vin <28v <35v inductor 47 uh 33uh the choice of which style inductor to use mainly depends on the price vs. size requirements and any emi requirements.
6 / 7 MA5604 major power technology co., ltd. rev. 1.0 jun . 04 , 201 4 ? t ypical characteristics p ower on : v in = 12 v, v out = 5 v, i load = 0 a c h1=sw , c h2=v out , c h3=v in , ch4=i out en on: v in = 12 v, v out = 5 v, i load = 5 a cable on: v in = 12 v, v out = 5 v, i load = 5 a c h1=sw , c h2=v out , c h3=v in , ch4=i out c h1=sw , c h2=v out , c h3=v in , ch4=i out
7 / 7 MA5604 major power technology co., ltd. rev. 1.0 jun . 04 , 201 4 ? package outlin es ? detail a l h e a a 2 a 1 e d 7 ( 4 x ) b y c detail a y x expose pad ? symbol dimensions in millimeters dimensions in inches 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 3.33 - 0.092 0.131 y - 2.34 2.54 - 0.092 0.10 0 o - 8 o 0 o - 8 o ? mold flash sh all not exceed 0.25mm per side ? jedec outline: ms - 012 ba
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