Abstract:
An ultrasonic transducer driving circuit configured to supply an output current and/or an output voltage to an output line for driving an ultrasonic transducer is provided. The ultrasonic transducer driving circuit includes a first current discharge circuit configured to allow a current arising from electric charges accumulated in the ultrasonic transducer to flow from the output line to ground when the output line is at a positive voltage, and a second current discharge circuit configured to allow the current arising from the electric charges accumulated in the ultrasonic transducer to flow from ground to the output line when the output line is at a negative voltage. The first current discharge circuit and the second current discharge circuit are controlled based on the output current and/or the output voltage.
Abstract:
A sensor assembly includes an impedance sensor element, an impedance sensor reader and a communications module. The communications module is configured to communicate with a remote computing device. The impedance sensor reader is coupled to the impedance sensor element. The impedance sensor reader includes a synthesizer and a detector. The synthesizer is configured to output an excitation signal having known values for a plurality of signal characteristics to the impedance sensor element and to generate the excitation signal based on a plurality of direct digital synthesizer (DDS) coefficients received from the remote computing device through the communications module. The detector is coupled to the impedance sensor element and configured to detect a response of the impedance sensor element to the excitation signal and determine an impedance of the impedance sensor element based at least in part on the response of the impedance sensor element to the excitation signal.
Abstract:
A system including a low noise amplifier is provided. The system further includes a coarse attenuation circuit coupled to an input of the low noise amplifier and configurable to attenuate an input signal by a coarse attenuation interval. The system also includes a fine attenuation circuit coupled in feedback with the low noise amplifier and configurable to attenuate the input signal by a fine attenuation interval, wherein the fine attenuation interval is less than the coarse attenuation interval.
Abstract:
A method for multivariable measurements using a single-chip impedance analyzer includes providing a sensor, exposing the sensor to an environmental parameter, determining a complex impedance of the sensor over a measured spectral frequency range of the sensor, and monitoring at least three spectral parameters of the sensor.
Abstract:
A sensor assembly includes an impedance sensor element, an impedance sensor reader and a communications module. The communications module is configured to communicate with a remote computing device. The impedance sensor reader is coupled to the impedance sensor element. The impedance sensor reader includes a synthesizer and a detector. The synthesizer is configured to output an excitation signal having known values for a plurality of signal characteristics to the impedance sensor element and to generate the excitation signal based on a plurality of direct digital synthesizer (DDS) coefficients received from the remote computing device through the communications module. The detector is coupled to the impedance sensor element and configured to detect a response of the impedance sensor element to the excitation signal and determine an impedance of the impedance sensor element based at least in part on the response of the impedance sensor element to the excitation signal.
Abstract:
A sensor assembly includes an impedance sensor element, an impedance sensor reader and a communications module. The communications module is configured to communicate with a remote computing device. The impedance sensor reader is coupled to the impedance sensor element. The impedance sensor reader includes a synthesizer and a detector. The synthesizer is configured to output an excitation signal having known values for a plurality of signal characteristics to the impedance sensor element and to generate the excitation signal based on a plurality of direct digital synthesizer (DDS) coefficients received from the remote computing device through the communications module. The detector is coupled to the impedance sensor element and configured to detect a response of the impedance sensor element to the excitation signal and determine an impedance of the impedance sensor element based at least in part on the response of the impedance sensor element to the excitation signal.
Abstract:
An ultrasonic transducer driving circuit configured to supply an output current and/or an output voltage to an output line for driving an ultrasonic transducer is provided. The ultrasonic transducer driving circuit includes a first current discharge circuit configured to allow a current arising from electric charges accumulated in the ultrasonic transducer to flow from the output line to ground when the output line is at a positive voltage, and a second current discharge circuit configured to allow the current arising from the electric charges accumulated in the ultrasonic transducer to flow from ground to the output line when the output line is at a negative voltage. The first current discharge circuit and the second current discharge circuit are controlled based on the output current and/or the output voltage.
Abstract:
A sensor assembly includes an impedance sensor element, an impedance sensor reader and a communications module. The communications module is configured to communicate with a remote computing device. The impedance sensor reader is coupled to the impedance sensor element. The impedance sensor reader includes a synthesizer and a detector. The synthesizer is configured to output an excitation signal having known values for a plurality of signal characteristics to the impedance sensor element and to generate the excitation signal based on a plurality of direct digital synthesizer (DDS) coefficients received from the remote computing device through the communications module. The detector is coupled to the impedance sensor element and configured to detect a response of the impedance sensor element to the excitation signal and determine an impedance of the impedance sensor element based at least in part on the response of the impedance sensor element to the excitation signal.
Abstract:
An impedance analyzer is provided. The analyzer includes a signal excitation generator comprising a digital to analog converter, where a transfer function of the digital to analog converter from digital to analog is programmable. The impedance analyzer further includes a receiver comprising a low noise amplifier (LNA) and an analog to digital converter (ADC), where the LNA is a current to voltage converter; where the programmable digital to analog transfer function is implemented by a direct digital synthesizer (DDS) and a voltage mode digital to analog converter, or a digital phase locked loop (PLL), or both. Further, a multivariable sensor node having an impedance analyzer is provided. Furthermore, a multivariable sensor network having a plurality of multivariable sensor nodes is provided.
Abstract:
An ultrasound probe analog to digital converter includes an input successive approximation register (SAR) first stage; and an output SAR second stage in communication with the input SAR first stage. The input SAR first stage includes a programmable preamplifier integrated therein for residue amplification. The preamplifier is programmed to alternate between a linear amplifier operating mode and a comparator operating mode.