RICOH R5108G SERIES Microprocessor Supervisory Circuit with SENSE pin User's Manual Data Sheet

R5108G SERIES

Microprocessor Supervisory Circuit with SENSE pin

NO.EA-171-111103

OUTLINE The R5108G Series are CMOS-based microprocessor supervisory circuit, or high accuracy and ultra low supply current voltage detector with built-in delay circuit and watchdog timer. When the SENSE voltage is down across the threshold, or the watchdog timer does not detect the system clock from the microprocessor, the reset output is generated. The voltage detector circuit is used for the system reset, etc. The detector threshold is fixed internally, and the accuracy is ±1.0%. The released delay time (Power-on Reset Delay) circuit is built-in, and output delay time is adjustable with an external capacitor, and the accuracy is ±16%∗. When the SENSE voltage becomes the released voltage, the reset state will be maintained during the delay time. The output type of the reset is selectable, Nch open-drain, or CMOS. The time out period of the watchdog timer can be also set with an external capacitor, and the accuracy is ±33%∗. There is a function to stop supervising clock by the watchdog timer (INH function). A necessary voltage source can be supervised with SENSE pin. There are another 4 products by the difference of packages and the function of voltage detector and watchdog timer. The package of R5108G is SSOP-8G.

FEATURES • Supply Current...................................................................... Typ. 11μA • Operating Voltage Range 1.5V to 6.0V < Voltage Detector Part > • Detector Threshold Range.................................................... 1.5V to 5.5V (0.1V steps) • Detector Threshold Accuracy................................................±1.0% • Power-on Reset Delay Time accuracy ±16%∗ (−40°C ≤ Topt ≤ 105°C) • Power-on reset delay time of the voltage detector Typ. 370ms with an external capacitor : 0.1μF • With SENSE pin....................................................................Able to keep “L” reset signal < Watchdog Timer Part > • Built-in a watchdog timer's time out period accuracy ±33%∗ (−40°C ≤ Topt ≤ 105°C) • Timeout period for watchdog timer Typ. 310ms with an external capacitor : 0.1μF • Reset timer for watchdog timer............................................. Typ. 34ms with an external capacitor : 0.1μF • With Inhibit pin (INH)............................................................. Able to stop watchdog timer • Package................................................................................SSOP-8G

∗) Accuracy to center value of (Min.+Max.)/2

APPLICATIONS • Supervisory circuit for equipment with using microprocessors.