PC Power Fail and Reset Controller

The DS1632 PC Power-fail and Reset Controller contains internal circuitry to implement a 32.768kHz oscillator with the addition of only a 6pF 32.768kHz crystal. The DS1632 switches between a battery and the incoming supply, depending on which is greater, with a voltage drop of less than 0.2 volts. It provides resets for both power-up and pushbutton input with automatic resets during power transients. A precision comparator constantly monitors the main power and signals a power failure. The DS1632 also monitors battery power and signals a low-battery condition.

Power resets, low battery flags, and power-fail flags make the DS1632 a versatile system manager, with extremely low-power circuitry that conserves system resources in battery-backed applications.

* Power-fail detect circuitry

* Pushbutton reset

* Reset pulse width of either 95ms or 190ms

* Active high and low resets

* Accurate 5% or 10% +5-volt power supply monitoring

* Battery switch

* On-chip 32.768kHz crystal oscillator

* Low battery warning

* 5-volt operation

* Thermal range: 0°C to +70°C