1 rev.1.0 parameter symbol limit unit vin power supply voltage vin -0.3 to +40 v apply voltage to fb vfb gnd-0.3 to vin v apply voltage to en ven gnd-0.3 to vin+0.3 v apply voltage to sw vsw gnd-0.3 to vin+0.3 v apply voltage to vc vc vin-20 to vin+0.3 v power dissipation pd 300 mw operating temperature range top -40 to +85 c storage temperature range tstg -65 to +150 c elm610d a 1.3a 36v pwm step down dc/dc converter general description features maximum absolute ratings ? pc motherboard ? lcd monitor ? graphic card ? dvd, blu-ray player ? telecom equipment ? adsl modem ? printer and other peripheral equipment ? microcomputer power supply ? network power supply application 7 - ? input voltage : 5.5v to 36v ? output voltage : 0.8v to vin ? output current : 1.3a ? duty ratio : 0% to 100% ? constant frequency : typ.150khz ? soft-start ? thermal shutdown protection ? short circuit protection ? built-in internal p-channel mos ? package : sop-8 ELM610DA consists of step-down switching regulator with pwm control, reference voltage source, oscillation circuit, error amplifier, internal pmos, etc. ELM610DA provides low-ripple power, high efficiency, and excellent transient characteristics; pwm control circuit is able to vary the duty ratio linearly from 0 up to 100%. ELM610DA also contains error ampli?er circuit as well as soft-start circuit that prevents overshoot at during startup. internal enable function, over current protect function and short circuit protect function will reduce the operation frequency from 150khz to 30khz when overmuch current or short circuit occurs. meanwhile, internal compensation block is able to minimize the quantity of required external component. with internal p-channel power mos, and externally connected coil, capacitor, and diode, ELM610DA is able to function as step-down switching regulator. by the small package of sop-8, ELM610DA is capable of working as ideal power supply units for portable devices while providing outstanding features such as low current consumption. since this converter accommodates input voltage up to 36v, ELM610DA is also suitable for operations which adopt ac adapter. caution: permanent damage to the device may occur when ratings above maximum absolute ones are used.
2 rev.1.0 sop-8(top view) 4 3 2 1 5 6 7 8 pin configuration 7 - pin no. pin name pin description 1 fb feedback(0.82v operation) 2 en enable / disable h: normal operation mode.(step-down operation) l: shutdown mode.(all circuits deactivated) 3 vc add an external capacitor to vin. the voltage is set to vin -7v 4 vin ic power supply 5, 6 sw switch. connect external inductor/diode to here. minimize trace area at this pin to reduce emi. 7, 8 gnd gnd standard circuit v i n s w f b e n v c r 1 g n d c c = 0 . 1 f / 1 6 v l = 2 2 h e l m 6 1 0 d a r 2 + - c i n = 3 3 0 f / 5 0 v 2 4 v c o u t = 3 3 0 f / 1 6 v d = 2 a / 4 0 v v o u t * taping direction is one way. ELM610DA-n symbol a package d: sop-8 b product version a c taping direction n: refer to pkg file ELM610DA - n a b c selection guide vout=vfb(1+r1/r2) elm610d a 1.3a 36v pwm step down dc/dc converter
3 rev.1.0 block diagram 7 - von/off en sw oscillation circuit error ampli?er pwm control circuit reference voltage source and soft start vin fb vc gnd thermal shutdown protection parameter symbol condition min. typ. max. unit input voltage vin 5.5 36.0 v en pin input voltage venh evaluate oscillation at sw pin 2.0 v venl evaluate oscillation stop at sw pin - 0.8 feedback voltage vfb iout=0.1a 0.803 0.820 0.836 v feedback bias current ifb iout=0.1a - 0.1 0.5 a current limit icl 2.0 a quiescent current (switch off) ignd en ven_h, vfb=1v 1 2 ma current consumption during power off ignd_off en ven_l 1 10 a voltage clamp vc no load vin-6 vin-7 vin-8 v oscillation frequency fosc 120 150 180 khz frequency of current limit or short circuit protect foscl 20 30 40 khz line regulation vout vout vin=12v to 36v, iout=0.2a 1 2 % load regulation vout vout iout=0.1 to 1.3a 0.2 0.5 % internal mosfet rdson rds(on) vfb=0v, iout=1a 80 100 m ef?ciency vin=24v, vout=5v, iout=1.3a 87 % electrical characteristics vin=24v, top=25 c , unless otherwise speci?ed elm610d a 1.3a 36v pwm step down dc/dc converter
4 rev.1.0 sop-8 marking e l m 6 1 0 da ab c application notes pwm control ELM610DA is dc/dc converter which consists pulse-width modulation (pwm) system. in converters of ELM610DA, the pulse width varies according toe the load current, within the range from 0 to 100%. the ripple voltage produced by switching can easily be removed through the ?lter since switching frequency remains con - stant; ELM610DA is capable of providing low-ripple power within broad ranges of input voltage and load cur - rent. test circuits v i n s w f b e n v c l = 2 2 h c c = 0 . 1 f e l m 6 1 0 d a r 1 r 2 v o u t g n d v i n r l c i n = 3 3 0 f d c o u t = 3 3 0 f 7 - elm610d a 1.3a 36v pwm step down dc/dc converter mark content ELM610DA product name abc assembly lot no.: 000 to 999 repeated
5 rev.1.0 typical characteristics 7 - 0 4 8 12 16 20 24 28 32 36 0.4 0.8 1.2 1.6 2.0 2.4 iout=1ma 10ma 100ma 1a vin (v) vout (v) vout-vin ? v=1.8v 0.1 1 10 100 1000 0 20 40 60 80 100 vin=6v vin=12v vin=24v iout (ma) efficiency (%) efficiency-iout -40 -20 0 20 40 60 80 0.80 0.85 0.90 top ( ? ) vfb (v) vfb-top vin=12v, iout=0.1a 0.1 1 10 100 1000 1.6 1.8 2 vin=24v vin=12v vin=6v iout (ma) vout (v) vout-iout 0 2 4 6 8 10 12 14 16 18 20 0 1 2 3 0 1 2 time (ms) start response vout (v) ven (v) vin=12v, no load 0 40 80 120 160 200 1.5 2 2.5 0 1 2 time (ms) load transient response vout (v) iout (a) vin=12v, iout=1ma ? 1a ? vout=1.8v : cin=330f, cout=330f, l=22h, r1=5.1k , r2=4.3k , top=25c elm610d a 1.3a 36v pwm step down dc/dc converter
6 rev.1.0 7 - 0 4 8 12 16 20 24 28 32 36 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 iout=1ma 10ma 100ma 1a vin (v) vout (v) vout-vin ? v=3.3v 0.1 1 10 100 1000 0 20 40 60 80 100 vin=6v vin=12v vin=24v iout (ma) efficiency (%) efficiency-iout 0.1 1 10 100 1000 3.1 3.2 3.3 3.4 3.5 vin=24v vin=12v vin=5v iout (ma) vout (v) vout-iout -40 -20 0 20 40 60 80 0.80 0.85 0.90 top ( ? ) vfb (v) vfb-top vin=12v, iout=0.1a 0 2 4 6 8 10 12 14 16 18 20 0 1 2 3 0 1 2 time (ms) start response vout (v) ven (v) vin=12v, no load 3.5 0 10 20 30 40 50 60 70 80 90 100 2.5 3 3.5 4 0 1 2 time (ms) load transient response vout (v) iout (v) vin=12v, iout=1ma ? 1a ? vout=3.3v : cin=330f, cout=330f, l=22h, r1=13.1k , r2=4.3k , top=25c elm610d a 1.3a 36v pwm step down dc/dc converter
7 rev.1.0 7 - 0 4 8 12 16 20 24 28 32 36 1.0 2.0 3.0 4.0 5.0 6.0 iout=1ma 10ma 100ma 1a vin (v) vout (v) vout-vin ? v=5.0v 0.1 1 10 100 1000 0 20 40 60 80 100 vin=6v vin=12v vin=24v iout (ma) efficiency (%) efficiency-iout 0.1 1 10 100 1000 4.6 4.8 5 5.2 vin=12v vin=6v iout (ma) vout (v) vout-iout vin=24v -40 -20 0 20 40 60 80 0.80 0.85 0.90 top ( ? ) vfb (v) vfb-top vin=12v, iout=0.1a 0 2 4 6 8 10 12 14 16 18 20 0 1 2 3 4 5 6 0 1 2 time (ms) start response vout (v) ven (v) vin=12v, no load 0 10 20 30 40 50 60 70 80 90 100 3 4 5 6 0 1 2 time (ms) load transient response vout (v) iout(a) vin=12v, iout=1ma ? 1a ? vout=5.0v : cin=330f, cout=330f, l=22h, r1=22k , r2=4.3k , top=25c elm610d a 1.3a 36v pwm step down dc/dc converter
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