UM805

UM805/811/812 4-Pin μP Voltage Monitors with Manual Reset Input UM805/811/812 SOT143 General Description The UM805/811/812 are low-power microprocessor (μP) supervisory circuits used to monitor power supplies 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 UM805/811/812 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 threshold. Reset thresholds are available for operation with a variety of supply voltages. The UM805 has an o_p__e__n__-_d__r__a_in output stage, while the UM811/812 have push-pull outputs. The UM805’s open-drain RESET output requires a pull-up _r__e_s__i_s__t_o__r_ that can be connected to a voltage higher than VCC. The UM805/8...