X40414, X40415 pdf datasheet (

The X40410/11/14/15 combines power-on reset control,
watchdog timer, supply voltage supervision, and
secondary voltage supervision, and Block Lock™ protect
serial EEPROM in one package. This combination
lowers system cost, reduces board space requirements,
and increases reliability.
Applying voltage to VCC activates the power-on reset
circuit which holds RESET/RESET active for a period of
time. This allows the power supply and system oscilla-Low VCC detection circuitry protects the user’s system
from low voltage conditions, resetting the system when
VCC falls below the minimum VTRIP1 point. RESET/RESET
is active until VCC returns to proper operating level
and stabilizes. A second voltage monitor circuit tracks
the unregulated supply to provide a power fail warning
or monitors different power supply voltage. Three common
low voltage combinations are available, however,
Intersil’s unique circuits allows the threshold for either
voltage monitor to be reprogrammed to meet special
needs or to fine-tune the threshold for applications requiring
higher precision.