MIC2779

The MIC2779 is a voltage monitor-uniquely designed to detect two separate voltage thresholds-combined with a delay generator and logic. It is designed for monitoring the battery supply of portable digital systems, particularly PDAs,pagers, and cellular telephones.

High- and low-voltage thresholds of MIC2779 can be adjusted independently,allowing for wide hysteresis. Voltage detection thresholds are accurate to 2%.

If the battery voltage falls below the low-voltage threshold, the output /RST or RST of MIC2779 is asserted and latched, preventing system operation until the battery is replaced or recharged.Internal logic prevents the output from chattering due to battery recovery or load removal. The output of MIC2779 is asserted for 140ms minimum) when a fresh battery is inserted. For applications requiring open-drain output, see MIC2778/MIC833.

The IC's power supply input is separate from the detector inputs, allowing the MIC2779 to be powered from a downstream supply, such a boost converter. Supply current is extremely low (1A, typical), making it ideal for portable applications.

A high-precision 1% grade is available. The MIC2779 is supplied in Micrel's IttyBitty™ 5-lead SOT-23-5 package.