Datasheet Microchip MIC2755

MIC2755
Battery Operated Supervisor General Description Features The MIC2755 is composed of multiple comparators, a
reset pulse generator, and logic. It is designed for
monitoring the battery supply of portable digital systems,
including PDAs and pagers.
The MIC2755 can detect three different battery states:
battery OK, low battery, and dead battery. The reset
(/RST) output is asserted for at least 700ms when a fresh
battery is inserted. The non-maskable interrupt output
(/NMI) is asserted when the battery voltage is below the
NTH threshold, indicating that high-power system
operations should not occur. If and when battery voltage
falls below the power-off threshold (PTH), the reset output
is asserted and latched, inhibiting system operation until
the battery is replaced or recharged.
All three voltage thresholds are set using external
resistors. A manual reset function can be implemented by
connecting a switch directly to the power on reset/manual
reset [RTH(/MR)] input. Internal circuitry detects switch
activation and generates a minimum 175ms debounced
reset signal. The MIC2755’s power supply input is
separate from the detector inputs to allow it to be powered
from a down-stream voltage, such as the output of a boost …