The MAX811/MAX812 are low-power microprocessor
(μP) supervisory circuits used to monitor power sup-
plies in μP and digital systems. They provide excellent
circuit reliability and low cost by eliminating external
components and adjustments when used with 5V-
powered or 3V-powered circuits. The MAX811/MAX812
also provide a debounced manual reset input.
These devices perform a single function:? They assert a
reset signal whenever the VCC supply voltage falls
below a preset threshold, keeping it asserted for at
least 140ms after VCC has risen above the reset thresh-
old. The only difference between the two devices is that
the MAX811 has an active-low RESET output (which is
guaranteed to be in the correct state for VCC down to
1V), while the MAX812 has an active-high RESET out-
put. The reset comparator is designed to ignore fast
transients on VCC. Reset thresholds are available for
operation with a variety of supply voltages.
Low supply current makes the MAX811/MAX812 ideal
for use in portable equipment. The devices come in a
4-pin SOT143 package.