A Long Reset-Time Power-On Reset Circuit With Brown-Out Detection Capability

A compact low-power on-chip power-on reset circuit with a brown-out detection capability is presented. With a pico-farad-order on-chip MOS capacitor, a long reset time is achieved. A prototype design implemented in a 0.18-μm CMOS process provides a reset signal with duration of hundreds of milliseconds. The embedded brown-out detection circuit can detect the event, as long as the brown-out duration is longer than the millisecond range. The chip consumes only 1 μA under a 1.8-V supply and occupies a 120 μm × 100 μm active area.