Patent ID: 9698770
Date: 2017-07-04
CPC Classifications: H03K

Claim:
1. A circuit, comprising: a bias generator for receiving an operating voltage generated by a power supply and generating a bias voltage in response to the received operating voltage; a shaper for generating, in response to the generated bias voltage, a shaped signal for indicating the operating voltage; a comparator for comparing a threshold reference voltage with the shaped signal and for generating, in response to the generated bias voltage, a comparison signal for indicating a result of the comparison; and a reset signal generator for generating, in response to the comparison signal, a reset signal for resetting protected circuitry powered by the operating voltage generated by the power supply; wherein the comparator is operable to delay, in response to the indication of the slew rate of the received operating voltage, the comparing a threshold reference voltage with the shaped signal; wherein the speeds of operation of the bias generator and the comparator collectively slow down or speed up in response to variations in the operating voltage; wherein the comparator includes a hysteresis circuit for forcing a first comparator node controlled by the threshold voltage to a high state and a second comparator node controlled by the shaped signal to a low state, the first and second nodes being forced by the hysteresis circuit during ramping of the power supply.