Abstract: A proximity sensor oscillator is disclosed having controlled charge. The proximity sensor oscillator includes a resonant circuit which oscillates at a frequency determined by the components of the resonant circuit and with a power loss that is inversely related to the distance that a sensor element of the resonant circuit is to a conductive object. The peak amplitude of the resonant circuit varies with power loss and therefore measurement of this parameter provides an indication of the proximity of the conductive object to the sensor element. Power is provided to the resonant circuit by metering a fixed charge to the resonant circuit just before the peak of the resonant circuit voltage by means of a transistor switching circuit.