System Reset PST575 MITSUMI System Reset Monolithic IC PST575 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 delay time generating circuit that can set the time by an external capacitor and resistor. It is ideal for use in multi-CPU systems because a fast-rising output waveform can be obtained. Features 1. Ultra-low current consumption 2. Low operating limit voltage 3. Output current high for ON 4. Hysteresis voltage provided in detection voltage 5. Delay time can set over a wide range using external capacitor and resistor. 6. 10 ranks of detection voltage ICCH=7.5µA typ. ICCL=400µA typ. 0.65V typ. 30mA typ. 50mV typ. 10µS~10S PST575 C : 4.5V typ. D : 4.2V typ. E : 3.9V typ. F : 3.6V typ. G : 3.3V typ. H : 3.1V typ. I : 2.9V typ. J : 2.7V typ. K : 2.5V typ. L : 2.3V typ. Package MMP-4A (PST575 M) DIP-8A (PST575 ) contains detection voltage rank * Applications 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. Pin Assignment 8 1 7 2 6 3 DIP-8A 5 4 3 GND 4 Cd 5 VOUT 7 VCC 4 3 1 2 MMP-4A 1 VCC 2 VOUT 3 Cd 4 GND System Reset PST575 MITSUMI Equivalent Circuit Diagram Absolute Maximum Ratings Item Storage temperature Operating temperature Power supply voltage Symbol TSTG TOPR VCC max. Allowable loss Pd Electrical Characteristics Item Detection voltage Hysteresis voltage Detection voltage temperature coefficient Low-level output voltage Output leakage current Circuit current while on Circuit current while off "H" transport delay time "L" transport delay time Operating power supply voltage Output current while on I Output current while on II Threshold voltage for delay time setting comparator (CO2) *1 : tpLH : V = (V typ.-0.4V) *2: V =V min.-0.15V CC CC S (Ta=25°C) S Rating -40~+125 -20~+75 -0.3~10 200 (MMP-3A) 300 (TO-92A) Units °C °C V mW (Ta=25°C) (Except where noted otherwise, resistance unit is Ω) Symbol Measuring circuit 1 Measurement conditions PST575C PST575D PST575E PST575F RL=470 PST575G VOL <= 0.4V PST575H VCC=H L PST575I PST575J PST575K PST575L RL=470, VCC=L H L V S/ T 1 RL=470, Ta=-20°C~+75°C VOL IOH ICCL ICCH tpLH tpHL VopL IOL I IOL II 1 1 1 1 2 2 1 1 1 Vtsh 1 VS VS 1 Typ. 4.5 4.2 3.9 3.6 3.3 3.1 2.90 2.70 2.50 2.30 50 Max. Units 4.7 4.4 4.1 3.8 3.5 V 3.3 3.05 2.85 2.65 2.45 100 mV ±0.01 %/°C VCC=Vs min.-0.05V, RL=470 0.1 VCC=7.5V VCC=Vs min.-0.05V, RL=∞ 400 VCC=Vs typ./0.85V, RL=∞ 7.5 Rd=100k, Cd=0.01µF 1 0.75 1.25 Rd=100k, Cd=0.01µF 1 6 RL=4.7kΩ, VOL =< 0.4V 0.65 VCC=Vs min.-0.05V, RL=0 8 30 Ta=-20°C~+75°C, RL=0 2 5 VCC=5.0V, Rd=100k, Cd=0.01µF 3.5 3.7 RL=4.7k, CL=100pF 0.4 V ±0.1 µA 650 µA 12.0 µA 1.75 mS 20 µS 0.85 V mA mA (VS typ.+0.4V), tpHL : VCC= (VS typ.+0.4V) Min. 4.3 4.0 3.7 3.4 3.1 2.9 2.75 2.55 2.35 2.15 25 * * * (VS typ.-0.4V), CL=100pF 3.9 V System Reset PST575 MITSUMI Measuring Circuit (Example: PST575C) [1] [2] Input pulse 0.8V 4.9 VS 4.1 0V Note: Input model is an example for PST575C (MMP-4P). Characteristics (Example: PST575C) VCC vs. VOUT VCC vs. ICC 500 8 7 VOUT (V) Ta=-20°C 400 6 5 Ta=25°C 4 ICC 300 (µA) 3 Ta=-25°C Ta=25°C Ta=75°C 2 1 0 1 2 3 Ta=75°C 200 4 5 6 7 8 VCC (V) 100 0 0 1 2 3 4 5 6 7 8 VCC (V) VS vs. Ta VS (V) VS vs. Ta 4.53 80 4.52 70 4.51 60 4.50 VS 50 (mV) 4.49 40 4.48 30 4.47 -40 20 -20 0 20 Ta (°C) 40 60 80 -40 -20 0 20 Ta (°C) 40 60 80 System Reset PST575 MITSUMI IOL vs. Ta VOL vs. Ta 60 300 50 250 IOL (mA) 40 VOL (mV) 30 20 200 150 100 10 -40 -20 0 20 40 60 80 50 -40 -20 0 Ta (°C) ICCH vs. Ta 20 40 60 80 40 60 80 Ta (°C) ICCL vs. Ta 10 500 9 8 lCCH (µA) ICCL 400 (µA) 7 6 300 5 4 -40 -20 0 20 40 60 80 -40 -20 0 20 Ta (°C) Ta (°C) tpLH vs. Ta Cd (Rd) vs. tpLH Rd=100k Cd=0.01µF (Mylar) 10.0 1.7 7 5 3 2 1.6 0 =1 d R 1.0 Cd (µF) 7 5 1.5 k 0k 0 =1 d R 3 2 1.3 1.2 k 70 =4 Rd 0.1 7 5 3 2 0.01 tpLH 1.4 (mS) 1.1 -40 0 20 Ta (°C) 1 2 34 5 7 10 2 34 5 7 100 2 3 4 5 7 1000 tpLH (mS) Pd vs. Ta 300 200 Pd (mW) 100 0 -20 0 25 50 Ta 75 (°C) 100 125 40 60 80 System Reset PST575 MITSUMI Timing Chart 7 6 5 VCC VS 4 3 VCC/VOUT (V) 2 VOUT 1 0 Variable Time Undefined RESET ON OFF Application Circuits (Pin numbers are for an example of MMP-4P.) 1. Normal hard reset Delay time (tPLH) ··1.3Cd Rd+0.007 (mS) = Cd : µF Rd : kΩ Note: Connect a capacitor between IC pins 1 and 2 if VCC line impedance is high. 2. Manual reset added Note: Use RL, CL and Rm to prevent manual switch chattering. Connect a capacitor between IC pins 1 and 2 if VCC line impedance is high. MITSUMI System Reset PST575 3. Battery checker (LED ON for high voltage) Note: Connect a capacitor between IC pins 1 and 2 if VCC line impedance is high. 4. Battery checker (LED ON for low voltage) Note: Connect a capacitor between IC pins 1 and 2 if VCC line impedance is high. 5. Hysteresis voltage UP method When increasing hysteresis voltage for stable system operation, determine RH as follows and connect externally. However, ICCH is -5000PPM/°C, so perform temperature compensation at RH when using over a wide temperature range. Hysteresis voltage UP amount ( Vsup) is ·· RH ICCL Vsup = Total hysteresis voltage ( Vstotal) is ·· Vs+ Vsup Vstotal = (Operation will be destabilized is RH is raised too much.) Note: Connect a capacitor between IC pins 1 and 2 if VCC line impedance is high.