GENERAL DESCRIPTION
The TC70/71 is a fully-integrated power supply monitor, watchdog and battery backup circuit in a space-saving 8-pin package.
When power is initially applied, the TC70/71 holds the processor in its reset state for a minimum of 500msec after VCC is in tolerance to ensure stable system start-up. After start-up, processor sanity is monitored by the on-board watchdog circuit. The processor must provide periodic high-to-low level transitions to the TC70/71 to verify proper execution. Should the processor fail to supply this signal within the specified timeout period, an out-of-control processor is indicated and the TC70/71 issues a momentary processor reset as a result. The TC70 also features a watchdog disable pin to facilitate system test and debug.

FEATURES
■ Maximum Functional Integration: Precision Power
   Supply Monitor, Watchdog Timer, External RESET
   Override, Threshold Detector and Battery Backup
   Controller in an 8-Pin Package
■ Generates Power-on RESET and Guards Against
   Unstable Processor Operation Resulting from
   Power "Brown-out"
■ Automatically Halts and Restarts an Out-of
   Control Microprocessor
■ Output Can be Wire-ORed, or Hooked to Manual
   RESET Pushbutton Switch
■ Watchdog Disable Pin for Easier Prototyping (TC70)
■ Voltage Monitor for Power Fail or Low Battery
   Warning (TC71)
■ Available in 8-Pin Plastic DIP or 8-Pin SOIC Packages
■ Cost Effective

TYPICAL APPLICATIONS
■ All Microprocessor-based Systems
■ Test Equipment
■ Instrumentation
■ Set-Top Boxes