Robust power-on reset circuit with brown-out detection

An on-chip power-on reset circuit with a brown-out detection capability is implemented in a 0.18 μm CMOS. A pF-order capacitor is charged with a proportional-to-absolute-temperature (PTAT) current from a bandgap reference with limited loop bandwidth and slow start-up feature, to generate a reset signal with high robustness and wide-range supply rise time. An embedded brown-out detector based on complementary voltage-to-current (V-to-I) conversion and current comparison can accurately respond to the brown-out event with high robustness over process and temperature when the supply is lower than 1.5 V and the brown-out duration is longer than 0.1 ms. The presented design with embedded offset voltage cancellation consumes a quiescent current of 8.5 μA from a 1.8 V supply and works over ambient temperature of -40° to 120°.