Pulse circuits for measuring the capacitance to ground of a plate may be used in control equipment to provide an indication of the proximity of a person or object to be sensed. Pulse circuits are disclosed that are made from sets of three or more electrical switching elements arranged so that each of...http://www.google.fr/patents/US6466036?utm_source=gb-gplus-shareBrevet US6466036 - Charge transfer capacitance measurement circuit
