TC32MEZB [Microchip]

The TC32M is a fully-integrated processor supervisor in a 3-pin package. It provides three important functions to safeguard processor sanity: precision power on/off RESET control, watchdog timer and external RESET override. On power-up, the TC32M holds the processor in the reset state for a minimum of 500msec after VDD is within tolerance to ensure a stable system start-up. Microprocessor sanity is monitored by the on-board watchdog circuit. The microprocessor must provide a high-to-low level shift (through an external resistor divider) on the RS pin of the TC32M. Should the processor fail to supply this signal within the specified timeout period (typically 700msec), an out-of-control processor is indicated and the TC32M issues a processor reset as a result. The output of the TC32M can be wire-ORed with a push-button switch (or electronic signal) to override the TC32M and unconditionally reset the processor. When connected to a push-button switch, the TC32M provides contact debounce. The TC32M is packaged in a space-saving TO-92 or SOT-223 package. It provides all of the functionality of the industry standard TC1232 in a smaller, lower cost configuration.

• Incorporates the Functionality of the Industry Standard TC1232 (Processor Monitor, Watchdog and Manual Override RESET Controller) into a Small, Lower Cost Package
• 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 Push-button Switch