mitsumi system reset pst574 system reset monolithic ic pst574 outline this ic functions in a variety of cpu systems and other logic systems, to detect power supply voltage and reset the system accurately when power is turned on or interrupted. this ultra-low current consumption low reset type system reset ic has a built-in fixed delay time generating circuit. it is ideal for use in multi-cpu systems because a fast-rising output waveform can be obtained. features package applications pin assignment 1. ultra-low current consumption i cch =7.5a typ. i ccl =400a typ. 2. low operating limit voltage 0.65v typ. 3. output current high for on 30ma typ. 4. hysteresis voltage provided in detection voltage 50mv typ. 5. built-in delay circuit with excellent delay time 50mv typ. temperature characteristics 6. 10 ranks of detection voltage pst574 c : 4.5v typ. h : 3.1v typ. d : 4.2v typ. i : 2.9v typ. e : 3.9v typ. j : 2.7v typ. f : 3.6v typ. k : 2.5v typ. g : 3.3v typ. l : 2.3v typ. mmp - 3a (pst574 m) to - 92a (pst574 ) * contains detection voltage rank . 1. reset circuits in microcomputers, cpus and mpus (especially multi-cpu sets) 2. logic circuit reset circuits. 3. battery voltage check circuits. 4. back-up power supply switching circuits. 5. level detection circuits. 123 to - 92a 3 1 2 mmp-3a 1 v cc 2 gnd 3 v out 1 v cc 2 gnd 3 v out products to be discontinued
mitsumi system reset pst574 equivalent circuit diagram absolute maximum ratings (ta=25c) electrical characteristics (ta=25c) (except where noted otherwise, resistance unit is ) item symbol rating units storage temperature t stg - 40~+125 c operating temperature t opr - 20~+75 c power supply voltage v cc max. - 0.3~10 v allowable loss pd 200 (mmp-3a) mw 300 (to-92a) item symbol measurement measurement conditions min. typ. max. units circuit pst574c 4.3 4.5 4.7 pst574d 4.0 4.2 4.4 pst574e 3.7 3.9 4.1 r l =470 pst574f 3.4 3.6 3.8 detection voltage v s 1v ol < = 0.4v pst574g 3.1 3.3 3.5 v v cc =h l pst574h 2.9 3.1 3.3 pst574i 2.75 2.90 3.05 pst574j 2.55 2.70 2.85 pst574k 2.35 2.50 2.65 pst574l 2.15 2.30 2.45 hysteresis voltage v s 1r l =470, v cc =l h l 25 50 100 mv detection voltage temperature v s / t 1 r l =470, ta= - 20c~+75c 0.01 %/c coefficient low-level output voltage v ol 1 v cc =v s min. - 0.05v, r l =470 0.1 0.4 v output leakage current i oh 1v cc =7.5v 0.1 a circuit current while on i ccl 1v cc =v s min. - 0.05v, r l = 400 650 a circuit current while off i cch 1v cc =v s typ./0.85v, r l = 7.5 12.0 a "h"transport delay time tplh 2 * 1 r l =4.7k, c l =100pf 250 400 600 s "l"transport delay time tphl 2 * 1 r l =4.7k, c l =100pf 6 20 s operation limit voltage vopl 1 r l =4.7k , v ol < = 0.4v 0.65 0.85 v output current while on ii ol i1v cc =vs min. - 0.05v, r l =0 8 30 ma output current while on ii i ol ii 1 * 2 ta= - 20c~+75c, r l =0 5m a * 1 : tplh : v cc =(v s typ. - 0.4v) (v s typ.+0.4v), tphl : v cc =(v s typ.+0.4v) (v s typ.-0.4v) * 2 : v cc =v s min. - 0.15v products to be discontinued
mitsumi system reset pst574 measuring circuit characteristics (example: pst574c) [1] [2] vcc vs. v out vcc vs. icc 8 7 6 5 4 3 2 1 012345678 v out (v) v cc (v) ta = - 25 c ta = 25 c ta = 75 c 500 400 300 200 100 0 012345678 i cc ( a) v cc (v) t a = - 20 c t a = 25 c t a = 75 c vs vs. ta vs vs. ta - 40 - 20 0 20 40 60 80 4.47 4.48 4.49 4.50 4.51 4.52 4.53 v s (v) t a ( c) v s (mv) t a ( c) - 40 - 20 0 20 40 60 80 20 30 40 50 60 70 80 0.8v v s 0v 4.9 4.1 note: input model is an example for pst574c. products to be discontinued
mitsumi system reset pst574 iol vs. ta vol vs. ta 60 50 40 30 20 10 - 40 - 200 20406080 i ol (ma) t a ( c) 300 250 200 150 100 50 - 40 - 200 20406080 v o l (mv) t a ( c) i cch vs. ta i ccl vs. ta 9 10 8 7 6 5 4 - 40 - 200 20406080 l cch ( a) t a ( c) 500 400 300 - 40 - 200 20406080 i ccl ( a) t a ( c) t plh vs. ta pd vs. ta - 40 - 200 20406080 t a ( c) 500 600 450 400 350 300 250 t plh ( s) 300 200 0 0 25 50 75 100 125 100 pd (mw) ta ( c) 6 5 7 4 3 2 1 0 v cc /v out (v) r eset v cc v out v s time on off undefined timing chart products to be discontinued
mitsumi system reset pst574 application circuits 1. normal hard reset note: connect a capacitor between ic pins 1 and 2 if v cc line impedance is high. 2. battery checker (led on for high voltage) note: connect a capacitor between ic pins 1 and 2 if v cc line impedance is high. 3. battery checker (led on for low voltage) note: connect a capacitor between ic pins 1 and 2 if v cc line impedance is high. 4. hysteresis voltage up method when increasing hysteresis voltage for stable system operation, determine rh as follows and connect externally. however, i cch is - 5000ppm/c, so perform temperature compensation at rh when using over a wide temperature range. hysteresis voltage up amount ( vsup) is vsup . = . rh i ccl total hysteresis voltage ( vstotal) is vstotal . = . vs + vsup (operation will be destabilized if rh is raised too much.) note: connect a capacitor between ic pins 1 and 2 if v cc line impedance is high. products to be discontinued
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