Abstract: Piezoelectric sensor controllers may facilitate detection and identification of various potential fault states with parameter measurements. In an illustrative embodiment of a piezoelectric-based sensor having response-parameter-based fault diagnosis, the sensor includes a piezoelectric transducer and a controller. The controller drives the piezoelectric transducer to generate bursts of acoustic energy and, based on a response of the piezoelectric transducer to said driving, identifies a corresponding transducer state from a set of potential states including multiple transducer fault states.

Abstract: Piezoelectric sensor controllers may facilitate detection and identification of various potential fault states with novel parameter measurements. In an illustrative embodiment of a piezoelectric-based sensor having a shorted-reverberation based resonant frequency measurement, the sensor includes a piezoelectric transducer that provides residual reverberation after being driven. The sensor further includes a controller that provides a low impedance path for the piezoelectric transducer during the residual reverberation and that measures current through the low impedance path to determine a resonant frequency of the piezoelectric transducer.

Abstract: An obstacle monitoring system includes a transducer that receives an ultrasonic echo from an obstacle and generates a signal based on the echo. The system further includes a controller coupled to the transducer that is calibrated based on a frequency response of the transducer and a coupling circuit. The system further includes circuitry generating a damping current, controlled by the controller, that reduces or eliminates reverberation of the transducer.

Abstract: An illustrative controller embodiment includes: a transmitter that causes reverberation of a piezoelectric transducer; and a linear damping module that measures characteristics of the reverberation and tunes at least one of a shunt resistance and a shunt reactance for the piezoelectric transducer based on said characteristics. An illustrative sensor embodiment includes: a piezoelectric transducer; and a transducer controller coupled to the piezoelectric transducer to transmit pulses and receive echoes for measuring distances. The controller includes a linear damping module with: a shunt resistance; a shunt inductance; and an optional switch that couples the shunt resistance and shunt inductance in parallel to the piezoelectric transducer to damp reverberation of the piezoelectric transducer after said transmit pulses. The controller measures at least one characteristic of said reverberation and responsively tunes the shunt resistance or the shunt inductance.

Abstract: Piezoelectric sensor controllers may facilitate detection and identification of various potential fault states with novel parameter measurements. In an illustrative embodiment of a piezoelectric-based sensor having a shorted-reverberation based resonant frequency measurement, the sensor includes a piezoelectric transducer that provides residual reverberation after being driven. The sensor further includes a controller that provides a low impedance path for the piezoelectric transducer during the residual reverberation and that measures current through the low impedance path to determine a resonant frequency of the piezoelectric transducer.

Abstract: Piezoelectric sensor controllers may facilitate detection and identification of various potential fault states with novel parameter measurements. In an illustrative embodiment of a piezoelectric-based sensor having response-parameter-based fault diagnosis, the sensor includes a piezoelectric transducer and a controller. The controller drives the piezoelectric transducer to generate bursts of acoustic energy and, based on a response of the piezoelectric transducer to said driving, identifies a corresponding transducer state from a set of potential states including multiple transducer fault states.

Abstract: In one embodiment, a transducer controller is configured to form a drive signal with a first frequency to drive a transducer. The drive signal has a period and a half-period and drives the transducer for a first portion of the half-period. The transducer controller is configured to, for a second portion of the half-period, sense a voltage formed by the transducer, measure portions of the voltage and estimate a phase error between the first frequency and a resonant frequency of the transducer, and to adjust the first frequency to a second frequency that reduces the phase error.

Abstract: An obstacle monitoring system includes a transducer that receives an ultrasonic echo from an obstacle and generates a signal based on the echo. The system further includes a controller coupled to the transducer that is calibrated based on a frequency response of the transducer and a coupling circuit. The system further includes circuitry generating a damping current, controlled by the controller, that reduces or eliminates reverberation of the transducer.

Abstract: In one embodiment, a transducer controller is configured to form a drive signal with a first frequency to drive a transducer. The drive signal has a period and a half-period and drives the transducer for a first portion of the half-period. The transducer controller is configured to, for a second portion of the half-period, sense a voltage formed by the transducer, measure portions of the voltage and estimate a phase error between the first frequency and a resonant frequency of the transducer, and to adjust the first frequency to a second frequency that reduces the phase error.

Abstract: An illustrative controller embodiment includes: a transmitter that causes reverberation of a piezoelectric transducer; and a linear damping module that measures characteristics of the reverberation and tunes at least one of a shunt resistance and a shunt reactance for the piezoelectric transducer based on said characteristics. An illustrative sensor embodiment includes: a piezoelectric transducer; and a transducer controller coupled to the piezoelectric transducer to transmit pulses and receive echoes for measuring distances. The controller includes a linear damping module with: a shunt resistance; a shunt inductance; and an optional switch that couples the shunt resistance and shunt inductance in parallel to the piezoelectric transducer to damp reverberation of the piezoelectric transducer after said transmit pulses. The controller measures at least one characteristic of said reverberation and responsively tunes the shunt resistance or the shunt inductance.

Abstract: A mode detector in a sensor interface is configured to detect a mode specified by a mode signal when an input signal received from a side of a first terminal is the mode signal. A communication portion in the interface transmits an electric signal, obtained from a sensor circuit, to a side of a second terminal when a mode detected with the detector is a sensor output mode. The communication portion receives an input signal from the side of the first terminal while transmitting an output signal to the side of the second terminal, when a mode detected with the detector is a communication mode.

Abstract: A mode detector in a sensor interface is configured to detect a mode specified by a mode signal when an input signal received from a side of a first terminal is the mode signal. A communication portion in the interface transmits an electric signal, obtained from a sensor circuit, to a side of a second terminal when a mode detected with the detector is a sensor output mode. The communication portion receives an input signal from the side of the first terminal while transmitting an output signal to the side of the second terminal, when a mode detected with the detector is a communication mode.