US Patent 7757565 Self-powered sensor

A self-powered sensor is provided for strain-rate monitoring and other low power requirement applications. The self-powered sensor is comprised of: a piezoelectric transducer; a non-volatile memory comprised of at least one floating gate transistor; a current reference circuit adapted to receive a voltage signal from the piezoelectric transducer and operable to output a reference current into the non-volatile memory; an impact-monitoring circuit having a triggering circuit and a switch; the triggering circuit adapted to receive the voltage signal from the piezoelectric transducer and operable to control the switch based on the rate of change of the voltage signal.