Maxim Integrated MAX820SCSE

Description
The MAX792/MAX820 microprocessor (μP) supervisory circuits provide comprehensive power-supply and watchdog monitoring for systems without battery backup. They feature:
μP Reset: RESET and RESET outputs are asserted during power-up, power-down, and brownout conditions. RESET is valid down to 1V.
Manual-Reset Input: Allows for manual reset.
Two-Stage Power-Fail Warning: A low-line comparator monitors Vcc and compares it to a preset threshold 120mV above the reset threshold.
Watchdog Fault Output: WDO is asserted if the watchdog input is not toggled within a preset timeout period.
Pulsed Watchdog Output: Provides advance warning of impending WDO assertion.
Write Protection: Protects CMOS RAM, EEPROM, or other memory devices.

Features
Independent watchdog timer (preset or adjustable)
On-board gating of chip-enable signals
Memory write-cycle completion
10ns (max) chip-enable gate propagation delay
Voltage monitor for overvoltage warning
±2% reset and low-line threshold accuracy (MAX820, external programming mode)

Applications
Computers
Controllers
Intelligent instruments
Critical μP power monitoring