Reliability comparator with hysteresis

• Main Authors: Bhattacharya, Dipankar, Kriz, John Christopher, Morris, Bernard L, Wilson, William B
• Format: Patent
• Language: English
• Published: 12.09.2006

A comparator circuit includes a reference generator connecting to a first source providing a first voltage. The reference generator is operative to generate a reference signal and includes a control circuit selectively operable in at least a first mode or a second mode in response to a first control signal, wherein in the first mode the reference signal is not generated, and in the second mode the reference generator is operative to generate the reference signal. The comparator circuit further includes a comparator connecting to a second source providing a second voltage, the second voltage being less than the first voltage. The comparator is operative to receive the reference signal and an input signal, and to generate an output signal which is a function of a comparison between the input signal and the reference signal. A hysteresis circuit is included in the comparator circuit for selectively controlling a switching threshold of the comparator, relative to the input signal, as a function of the output signal of the comparator. The comparator circuit includes a voltage clamp operative to limit a voltage applied to one or more devices in the control circuit, the comparator, and/or the hysteresis circuit to less than the second voltage.