Patent ID: 9081038
Filing Date: 2015-07-14
Classification: G01R,H03F

Abstract:
1. A voltage monitor comprising: a voltage reference circuit configured to be controllably de-powered and re-powered; a sampling circuit coupled to the voltage reference circuit, the sampling circuit configured to: a first capacitive circuit configured to provide a representation of an input voltage; and a comparator circuit having first and second inputs, the first input of the comparator circuit coupled to the sampling circuit to receive the representation of the sampled voltage of the voltage reference and the second input of the comparator circuit coupled to the first capacitive circuit to receive the representation of the input voltage; a switching circuit configured to sample an offset voltage at an output of the comparator circuit onto at least one capacitor included in the first capacitive circuit; wherein the comparator circuit is configured to provide an output signal indicative of a comparison between the first and second inputs at least when the voltage reference circuit is de-powered; wherein the output signal includes offset compensation provided using the sampled offset voltage; and wherein the voltage reference circuit is configured to be re-powered in coordination with the sampling circuit for a stabilization duration before the sampling circuit samples the voltage provided by the voltage reference.