Aspects of the technology described herein relate to an ultrasound device that may has a phase-locked loop (PLL) that includes a digitally-controlled oscillator (DCO). The DCO includes a plurality of current source unit cells with respective drain switches a plurality of current source unit cells with respective source switches. The plurality of current source unit cells with respective drain switches and the plurality of current source unit cells may have different circuit topologies. Switching on one of the plurality of current source unit cells with respective drain switches may cause a voltage transition at an internal node proceeding in one voltage direction and switching on one of the plurality of current source unit cells with respective source switches may cause a voltage transition at an internal node proceeding in the opposite voltage direction.

A circuit for generating and detecting ultrasonic sensing signals is provided. A piezoelectric device having a transmitting electrode and a receiving electrode is coupled to a biasing-and-sampling sub-circuit configured to set different bias voltages to the receiving electrode. The piezoelectric device is configured to transmit an ultrasonic signal upon applying an exciting pulse signal to the transmitting electrode and alternatively to generate a voltage signal at the receiving electrode upon receiving an echo signal based on the ultrasonic signal. A signal-collecting sub-circuit is coupled to the receiving electrode to determine a first sampling voltage based on the voltage signal at the receiving electrode in a first sampling period and a second sampling voltage based on the voltage signal at the receiving electrode in a second sampling period. An output sub-circuit is coupled to the signal-collecting sub-circuit for outputting the first sampling voltage and the second sampling voltage at a same time.

A measurement and imaging instrument capable of beamforming with high speed and high accuracy without approximate calculation. The instrument includes a reception unit which receives a wave arriving from a measurement object to generate a reception signal; and an instrument main body which performs a lateral modulation while superposing two waves in a two-dimensional case and three or four waves in a three-dimensional case in beamforming processing of the reception signal in which at least one wave arriving from the measurement object is processed as being transmitted or received in the axial direction or directions symmetric with respect to the axial direction to generate a multi-dimensional reception signal, performs Hilbert transform with respect to the multi-dimensional reception signal, and performs partial derivative processing or one-dimensional Fourier transform to generate analytic signals of the multi-dimensional reception signals of the two waves or the three or four waves.

Provided are a two-dimensional array ultrasonic probe and an addition circuit that switch an addition unit of a reception signal according to a reception channel of a main unit while preventing an increase in a chip area. The addition circuit includes, between addition output terminals that output an addition signal and transducer channels, wirings provided for each transducer channel row including the transducer channels arranged in a vertical direction on a subarray basis and coupled to the transducer channels of the corresponding transducer channel row, output switches provided for each of the wirings and coupled to the corresponding transducer channel row wiring, and an inter-output switch that couples wirings corresponding to transducer channel rows adjacent in the horizontal direction via the output switches.

An imaging device includes a transducer that includes an array of piezoelectric elements formed on a substrate. Each piezoelectric element includes at least one membrane suspended from the substrate, at least one bottom electrode disposed on the membrane, at least one piezoelectric layer disposed on the bottom electrode, and at least one top electrode disposed on the at least one piezoelectric layer. Adjacent piezoelectric elements are configured to be isolated acoustically from each other. The device is utilized to measure flow or flow along with imaging anatomy.

A variable current trans-impedance amplifier (TIA) for an ultrasound device is described. The TIA may be coupled to an ultrasonic transducer to amplify an output signal of the ultrasonic transducer representing an ultrasound signal received by the ultrasonic transducer. During acquisition of the ultrasound signal by the ultrasonic transducer, one or more current sources in the TIA may be varied.

A method for determining a geometry of an ear canal or a portion of an ear of a person may include filling the ear canal and/or the portion of the ear with a liquid or a gel, inserting a capacitive micromachined ultrasonic transducer probe or a piezoelectric micromachined ultrasonic transducer probe, acquiring data using the probe, and processing the acquired data to obtain a 2D or 3D image of the ear canal and/or the portion of the ear.

A circuit for generating and detecting ultrasonic sensing signals is provided. A piezoelectric device having a transmitting electrode and a receiving electrode is coupled to a biasing-and-sampling sub-circuit configured to set different bias voltages to the receiving electrode. The piezoelectric device is configured to transmit an ultrasonic signal upon applying an exciting pulse signal to the transmitting electrode and alternatively to generate a voltage signal at the receiving electrode upon receiving an echo signal based on the ultrasonic signal. A signal-collecting sub-circuit is coupled to the receiving electrode to determine a first sampling voltage based on the voltage signal at the receiving electrode in a first sampling period and a second sampling voltage based on the voltage signal at the receiving electrode in a second sampling period. An output sub-circuit is coupled to the signal-collecting sub-circuit for outputting the first sampling voltage and the second sampling voltage at a same time.

An ultrasound circuit comprising a multi-stage trans-impedance amplifier (TIA) is described. The TIA is coupled to an ultrasonic transducer to amplify an electrical signal generated by the ultrasonic transducer in response to receiving an ultrasound signal. The TIA may include multiple stages, at least two of which operate with different supply voltages. The TIA may be followed by further processing circuitry configured to filter, amplify, and digitize the signal produced by the TIA.

A filter circuit for an imaging device including a probe configured to propagate an ultrasonic wave through an object includes a diode bridge configured to receive, from a transducer of the probe, a composite signal that includes a test signal and a reflected signal. The reflected signal corresponds to reflected waves sensed by the transducer in response to the ultrasonic wave propagated through the object. The diode bridge is further configured to block the test signal from the composite signal and pass the reflected signal. The filter circuit further includes an output node configured to output the reflected signal and a first node and a second node that connect the diode bridge to a bias voltage. The bias voltage causes a bias current to flow from the first node to the second node through the diode bridge.