1 / 5 ML63 ML63 series dc - dc converter v application u power source of portable products u palmtops u portable cameras and video recorders u wireless mouse and keyboard v features l small number of external components: inductor, diode and capacitor. l ultra low input current : typical 0.6ua (at no load, 1.5v input) l oscillator : 100 khz, 180 khz ( + 15%) l low ripple and noise l low startup voltage : max 0.9v (with 1ma input) l high efficiency: typical 80% l package available: sot - 89 (500mw) & to - 92 (300mw) v absolute maximum ratings parameter symbol ratings units in put voltage v in 8 v output current i out 500 ma output voltage v out v ss - 0.3 ~v in +0.3 v sot - 89 500 continuous total power dissipation to - 92 p d 300 mw operating ambient temperature t opr - 30 ~ +80 o c storage temperature t stg - 40 ~ +125 o c v general description the ML63 is a group of vfm step - up dc/dc converter ic with ultra - low supply current by cmos process. it consists of an oscillator, a vfm control circuit, a lx switch driver transistor, a reference voltage unit, an error amp lifier for voltage detection and an lx switch protection circuit. it is suitable for use with battery - powered instruments with low noise and ultra low supply current. v block diagram v lx limiter buffer osc 100khz/180khz vref vfm control out error amp . lx vss lxsw
2 / 5 ML63 v electrical characteristics vin = 1.6v, iout = 10ma, ta = 25 o c, unless otherwise provided . ML63271 / ML63271a vout=2.7v parameter symbol conditions min typ max units output voltage v out 2.633 2.700 2.767 v startup voltage v start i out =1ma 0.8 0.9 v hold - on vol tage v hold i out =1ma 0.7 v type = ML63271a 85 100 115 khz oscillator frequency f osc type = ML63271 153 180 207 khz input current 1 i in1 at no load 8 12 ua input current 2 i in2 v in = 3.2v 6 ua lx switching current i lx v lx =0.4v, v in =2.55v 40 ma lx leakage current i lxleak v in =3.5v, v lx =6.0v 0.5 ua oscillator duty cycle maxdty measuring lx waveform 75 % efficiency eff 80 % input voltage v in 8 v vin = 1.8v, iout = 10ma, ta = 25 o c, unless otherwise provided . ML63301 / ML63301a vout= 3.0v parameter symbol conditions min typ max units output voltage v out 2.925 3.000 3.075 v startup voltage v start i out =1ma 0.8 0.9 v hold - on voltage v hold i out =1ma 0.7 v type = ML63301a 85 100 115 khz oscillator frequency f osc type = ML63301 153 180 207 khz input current 1 i in1 at no load 8 12 ua input current 2 i in2 v in = 3.5v 6 ua lx switching current i lx v lx =0.4v, v in =2.85v 40 ma lx leakage current i lxleak v in =3.5v, v lx =6.0v 0.5 ua oscillator duty cycle maxdty measuring lx waveform 75 % efficiency eff 80 % input voltage v in 8 v vin = 1.8v, iout = 10ma, ta = 25 o c, unless otherwise provided . ML63501 vout= 5 .0v parameter symbol conditions min typ max units output voltage v out 4.925 5.000 5.075 v startup volta ge v start i out =1ma 0.8 0.9 v hold - on voltage v hold i out =1ma 0.7 v oscillator frequency f osc 85 100 115 khz input current 1 i in1 at no load 8 12 ua input current 2 i in2 v in = 3.5v 6 ua lx switching current i lx v lx =0.4v, v in =2.85v 40 ma lx lea kage current i lxleak v in =3.5v, v lx =6.0v 0.5 ua oscillator duty cycle maxdty measuring lx waveform 75 % efficiency eff 80 % input voltage v in 8 v
3 / 5 ML63 v application notes note on use 1. it is recommended to use capacitor with a capacity of 10uf or more for good frequency characteristics, otherwise it will lead to high output ripple. tantalum type capacitor is recommended. as there may be the case where a spike - shaped high voltage is generated by the induct or when lx transistor is turned off, the operating voltage of capacitor should be at least three times of the output set voltage so as to avoid over - voltage damage. 2. it is recommended to use inductor has sufficiently small d.c. resistance, large allowab le current and hardly reaches magnetic saturation. when the inductance of inductor is small, there may be the case that the inductor current exceeds the absolute maximum ratings at the maximum load condition. 3. it is recommended to place external compone nts as close as possible to the dc/cd converter so as to minimize the interconnection parasitic between components and dc/dc converter, especially for the capacitor connected to vout pin. it is recommended to place 0.1uf ceramic capacitor between vout pin and vss pin. 4. it is recommended to provide sufficient grounding for vss pin. this will help to stable the zero level within dc/dc converter induced by the switching current level variation during operation. and the insufficient grounding may result in u nstable operation of dc/dc converter. v pin configuration sot - 89 : pin number pin name description 1 vss ground 2 vout voltage output/internal power supply 3 lx switch to - 92 : pin number pin name descript ion 1 vss ground 2 vout voltage output/internal power supply 3 lx switch
4 / 5 ML63 typical application circuit 1. step - up circuit 2. step - down circuit 3. step - up/step - down circuit note : the starter circuit is necessary for above circuits. typical value: inductor : 270uh capacitor: aluminium type, 4.7uf. diode: schottky diode with forward voltage drop of 0.2v or less
5 / 5 ML63 rev description date first official specification 23 /10/02 v ordering information v history of revision designator description output voltage eg. 27=2.7v 30=3.0v a 50=5.0v b oscil lator frequency 1 = 180khz 1a = 100khz c package type p = sot - 89 t = to - 92 d device orientation r = embossed tape (orientation of device : right) l = embossed tape (orientation of device : left) b = bag (to - 92) the information presente d in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. no liability will be accepted by the publisher for any consequence of its use.
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