System Reset PST91XX MITSUMI System Reset Monolithic IC PST91XX Series Outline The function of this low reset type IC is to accurately reset systems after detecting the supply voltage at the time of switching power on and instantaneous power off in various CPU and other logic systems. Further, this IC, with its super low consumption current and high precision voltage detection capacity, is most suited as a voltage check circuit for a number of products which use batteries. Features 1. High precision voltage detection Vs±3% max. 2. Super low current consumption ICCH=1.5µA typ. ICCL=1.0µA typ. 3. Low operating threshold voltage 0.65V typ. 4. Hysteresis voltage is provided as a detect voltage 50mV typ. 5. Large output current at the time ON 15mA typ. 6. The detect voltage can be selected at your discretion at 0.1V step within the range of 1.9 to 4.6V by the following stipulation method. PST91XX Detected voltage value (Example : for 4.2V ······ PST9142) Package TO-92A (PST91 SOT-25A (PST91 ) N) Applications 1. Reset circuits for microcomputers, CPU and MPU. 2. Reset circuit for logic circuitry. 3. Battery voltage check circuit. 4. Circuit for changing over to backup battery. 5. Level detecting circuit. Pin Assignment 5 1 2 3 TO-92A 1 VOUT 2 VCC 3 GND 1 4 2 3 SOT-25A (TOP VIEW) (Note) The pin 2 of SOT-25 package is a SUB terminal. Connect it to GND. 1 NC 2 SUB 3 GND 4 VOUT 5 VCC System Reset PST91XX MITSUMI Equivalent Circuit Diagram Absolute Maximum Ratings Item Storage temperature Operating temperature Power supply voltage (Ta=25°C) Symbol TSTG TOPR VCC * Pd Allowable loss Note: Ratings -40~+125 -20~+75 -0.3~+10 150 (SOT-25A) 300 (TO-92A) Units °C °C V mV *Some models have an expanded temperature range (-30 ~ +85°C). Electrical Characteristics Item (Ta=25°C) (The unit of resistance is Ω unless otherwise indicated.) Symbol Measurement Circuit Measurement conditions Min. Typ. Max. Units 4.6~ VS Detection Voltage 1 RL=470, VOL <= 0.4V VCC=H L -3% 1.9 +3% typ. (0.1V typ. V step) VS 1 RL=470, VCC=L VS/ T 1 RL=470, Ta=-20~+75°C ±0.01 Low Level Output Voltage VOL 1 VCC=VS min.-0.05V, RL=470 0.2 Output Leakage Current IOH 1 VCC=10V, VO=VCC Circuit Current at ON Time ICCL 1 VCC=VS min.-0.05V, RL=∞ Circuit Current at OFF Time ICCH 1 "H" Transmission Delay Time tpLH "L" Transmission Delay Time Hysteresis Voltage Detection Voltage Temperature Coefficient 1 * H L 30 50 100 mV %/°C 0.4 V ±0.1 µA 1.0 2.0 µA VCC=VS typ./0.85V, RL=∞ 1.5 2.5 µA 2 CL=100pF, RL=4.7k 20 60 µs tpHL 2 CL=100pF, RL=4.7k 20 60 µs Operating Threshold Voltage VOPL 1 RL=4.7k, VOL <= 0.4V 0.65 0.85 V Output Current at ON Time 1 IOL1 1 VO=0.4V RL=0, 5 mA VCC=VS min.-0.05V, VO=0.4V Output Current at ON Time 2 1 * Note: IOL2 1 Ta=-30~+80°C, VO=0.4V RL=0, VCC=VS min.-0.15V *1 Some models have an expanded temperature range (-30 ~ +80°C). 3 mA System Reset PST91XX MITSUMI Application Circuits Characteristics (Example: PST9145) VS vs. Ta IOL vs. Ta 40 4.65 4.60 35 4.55 VS (mV) IOL 30 (mA) 4.50 4.45 25 4.40 4.35 Ta 100 90 80 70 60 VS 50 (mV) 40 30 20 10 0 2.5 2 1.5 1 0.5 -20-10 0 10 20 30 40 50 60 70 Ta VopL (V) -20-10 0 10 20 30 40 50 60 70 Ta (°C) (°C) VOpL vs. Ta 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 Ta (°C) VS vs. Ta 3 0 -20-10 0 10 20 30 40 50 60 70 (°C) ICCH vs. Ta ICCH (µA) 20 -20-10 0 10 20 30 40 50 60 70 VOL vs. Ta VOL (mV) 240 220 200 180 160 140 120 100 80 60 -20-10 0 10 20 30 40 50 60 70 -20-10 0 10 20 30 40 50 60 70 Ta (°C) Ta (°C)