Self-resetting comparator circuit and method

摘要

A comparator circuit and method for comparing first and second inputs. First and second input capacitors are provided for storing first and second voltages indicative of the first and second inputs when the circuit is in a sample phase. A comparator stage coupled to the first and second input capacitors switches from a measure state to one of first and second output states when the comparator circuit is in a hold phase based upon the relative magnitudes of the first and second inputs. Reset circuitry operates to discharge the input capacitors when the comparator stage switches to one of the output states. During a subsequent sample phase, the discharged input capacitors can be rapidly charged to new voltages thereby increasing the operating speed of the comparator circuit.