Patent ID: 8283934
Filing Date: 2012-10-09
Classification: H03K

Abstract:
1. A capacitance sensor comprising: a first charging voltage detector configured to detect a change in a voltage loaded into a first capacitor between a first electrode and a ground terminal; a second charging voltage detector configured to detect a change in a voltage loaded into a second capacitor between the first electrode and a second electrode; and a determiner configured to generate a determination signal based on a detection voltage transmitted from each of the first charging voltage detector and second charging voltage detector, wherein the first charging voltage detector includes: a first comparator configured to compare a first detection voltage obtained from the first detection operation of the detection circuit with a first threshold; a first counter configured to count an output from the first comparator, the second charging voltage detector includes: a second comparator configured to compare a second detection voltage obtained from the second detection operation of the detection circuit with a second threshold; a second counter configured to count an output from the second comparator, wherein the determiner is configured to output the determination signal when detecting an output of the first counter and an output of the second counter.