AN400 - Generating a Power-Fail Interrupt using the F-RAM Processor Companion Power- Fail Comparator

AN400 describes the implementation of an early power-fail warning using the general-purpose comparator on the F-RAM Integrated Processor Companion. This warning signal can be used to drive a microcontroller interrupt input.

Overview

The F-RAM integrated Processor Companion features a general-purpose comparator that can be used to generate an early power-fail interrupt (PFI). This warning signal can drive a microcontroller interrupt input and must occur before VDD drops too low to save all critical data to the nonvolatile RAM. The Processor Companion’s early power-fail interrupt can also be used as a warning to the system to stop conducting critical activity during a brownout condition.