The STM690A/692A/703/704/802/805/817/818/819 supervisors are self-contained devices which provide microprocessor supervisory functions with the ability to non-volatize and write-protect external LPSRAM. A precision voltage reference and comparator monitors the VCCinput for an out-of-tolerance condition. When an invalid VCCcondition occurs, the reset output (RST) is forced low (or high in the case of RST). These devices also offer a watchdog timer (except for STM703/704/819) as well as a power-fail comparator (except for STM818) to provide the system with an early warning of impending power failure. These devices are available in a standard 8-pin SOIC package or a space-saving 8-pin TSSOP package.