LP3470

LP3470 Tiny Power On Reset Circuit June 1999 LP3470 Tiny Power On Reset Circuit General Description The LP3470 is a micropower CMOS voltage supervisory circuit designed to monitor power supplies in microprocessor (µP) and other digital systems. It provides maximum adjustability for power-on-reset (POR) and supervisory functions. It is available in the following six standard reset threshold voltage (VRTH) options: 2.63V, 2.93V, 3.08V, 4.00V, 4.38V, and 4.63V. If other voltage options between 2.4V and 5.0V are desired please contact your National Semiconductor representative. The LP3470 asserts a reset signal whenever the VCC supply voltage falls below a reset threshold. The reset time-out period is adjustable using an external capacitor. Reset remains asserted for an interval (programmed by an external capacitor) after VCC has risen above the threshold voltage. The device is available in the tiny SOT23-5 package. n Custom Reset Threshold Voltages: For other voltages between 2.4V and 5.0V contact your National Semiconductor representative n Very Low Quiescent Current (16 µA typical) n Guaranteed Reset valid down to VCC=0.5V Features n Tiny SOT23-5 Package n Open Drain Reset Output n Programmable Reset Timeout Period Using an External Capacitor n Immune to Short VCC Transients Applications n n n n Critical µP and µC Power Monitoring Intelligent Instruments Computers Portable/Battery-Powered Equipments Key Specifications n ± 1% Reset Threshold Accuracy Over Temperature n Sta...