Patent ID: 7283922
Filing Date: 2007-10-16
Classification: B60C

Abstract:
1. A transducer adapted to respond to transmitted signals of a given frequency for providing a bias potential to said transducer and for enabling said transducer to transmit a transducer output signal to a remote location, comprising: a radio antenna for receiving transmitted radio signals; a rectifier circuit coupled to said antenna and operative to provide a DC operating voltage in response to said received radio signals; a piezoresistive array operative to provide an output signal indicative of an applied pressure when said array is biased; a switch coupled to said rectifier circuit and said array and operative in a first mode to apply said DC operating bias to said array, and operative in a second mode to remove said operating bias; and an interface circuit coupled to said switch and said array and operating said switch in said first mode during the presence of received radio signals to cause said array to provide said output signal and apply said output signal to said antenna for transmission of said output signal to said remote locations, said interface circuit operative to operate said switch in said second mode when said transmitted radio signals are not received; wherein, said interface circuit is further coupled to said rectifier circuit to receive an operating bias from said rectifier circuit.