Ultrasense Systems, Inc.

Robert Boschgmbh

Ultrasense System, Inc.

Man-Chia Chen

Hao-Yen Tang

Sina Akhbari

Mo Maghsoudnia

Chinwuba Ezekwe

Saikrishna Ganta

Zhongxuan Tu

Michael Kerby Chen

Michael Chen

A force-measuring and touch-sensing integrated circuit device includes a semiconductor substrate, a thin-film piezoelectric stack overlying the semiconductor substrate, piezoelectric micromechanical force-measuring elements (PMFEs), and piezoelectric micromechanical ultrasonic transducers (PMUTs). The thin-film piezoelectric stack includes a piezoelectric layer. The PMFEs and PMUTs are located at respective lateral positions along the thin-film piezoelectric stack, such that each of the PMFEs and PMUTs includes a respective portion of the thin-film piezoelectric stack. Each PMUT has a cavity, the respective portion of the thin-film piezoelectric stack, and first and second PMUT electrodes. Each PMFE has the respective portion of the thin-film piezoelectric stack, and first and second PMFE electrodes. Each PMFE is configured to output voltage signals between the PMFE electrodes in accordance with a time-varying strain at the respective portion of the piezoelectric layer resulting from a low-frequency mechanical deformation.

Force-measuring and touch-sensing integrated circuit device

A method includes receiving energy data associated with an ultrasound input device coupled to a material layer. The energy data comprises a current energy value and past energy values associated with reflected ultrasound signals received at the ultrasound input device in response to the ultrasound input device transmitting emitted signals through the material layer towards an external surface of the material layer. The method can then include comparing the energy data with threshold data to generate a current trigger value for trigger data. The trigger data is indicative of an occurrence of a touch event when the current energy value exceeds a current threshold value of the threshold data. Then the method can include updating the threshold data based on the energy data, the trigger data, and the threshold data. Updating the threshold data comprises generating a subsequent threshold value.

Ultrasonic touch detection and decision

Reference scaling, op amp balancing and chopper stabilization techniques for delta-sigma modulators of analog-to-digital converters are provided. For reference scaling, unit elements in a feedback digital-to-analog (DAC) converter are driven by a reference voltage or disconnected from active circuitry to realize three DAC levels. While disconnected, the unit elements deliver no charge to the device which results in power saving and a reduction in thermal noise. Op amp balancing involves down-sampling the quantizer output followed by up-sampling on the feedback path and filtering to hold a DAC value of the signal for a duration of a sampling period to generate the feedback signal. Chopper stabilization is performed by chopping an operational transconductance amplifier of the integrator at a chopping frequency equal to the sampling frequency.

Power reduction and performance enhancement techniques for delta sigma modulator

Touch events can be detected using an ultrasound input device coupled to a surface, such as a surface of a piece of furniture or electronic device. The ultrasound input device can generate ultrasonic waves in the surface, the reflections of which can be measured by the ultrasound input device. When a touch is made to the surface (e.g., opposite the ultrasound input device), the physical contact can absorb some of the energy of the outgoing ultrasonic waves (e.g., the originally transmitted wave and any subsequent outgoing reflections). Energy measurements associated with the measured reflections can thus be used to identify touch events. Various techniques can be used to make the energy measurements and reduce identification of false touch events.

Ultrasonic touch and force input detection

A touch sensor chip can comprise an ultrasound sensor layer comprising an array of ultrasonic transducers. The array of ultrasonic transducers can comprise one or more ultrasonic transducers. The touch sensor chip can also comprise an integrated circuit layer coupled to the ultrasound sensor layer. The integrated circuit layer can comprise circuitry configured for driving the array of ultrasonic transducers to generate ultrasound signals and receiving reflected ultrasound signals using the array of ultrasonic transducers. The integrated circuit layer can also comprise circuitry configured for generating an energy signal associated with received reflected ultrasound signals.

Ultrasonic touch sensor and system

A stacked switched resistance device has been developed. The stacked switched resistance device includes a plurality of segments connected in series. Each segment includes a resistor including an inherent parasitic capacitance, and a switch connected in series with the resistor, the switch being configured to connect and disconnect the resistor from the plurality of segments in response to a predetermined clock signal. An effective resistance of the stacked switched resistance device exceeds another effective resistance of at least one resistor with an equivalent inherent resistance that is connected in series to a single switch configured to connect and disconnect the at least one resistor in response to the predetermined clock signal.

Switched resistance device with reduced sensitivity to parasitic capacitance

An ultrasound input device can be coupled to a material layer having an external surface located opposite the material layer from the ultrasound input device. The ultrasound input device can transmit an emitted signal through the material layer towards the external surface and receive a set of reflected ultrasound signals associated with the emitted signal. The set of reflected ultrasound signals comprises at least one reflected ultrasound signal, and the set of reflected ultrasound signals can be associated with a touch event between an object and the external surface. A system can comprise one or more data processors configured for performing operations including determining an energy signal associated with the set of reflected ultrasound signals, extracting feature information associated with the energy signal, determining an inference associated with the object based on the extracted feature information, and generating an output signal associated with the determined inference.

Ultrasonic touch feature extraction

A current sensing system and delta sigma modulator architecture are discloses for sensing and digitizing a current input signal from a high impedance signal source with improve power efficiency. The delta sigma modulator integrates a signal condition stage within the delta sigma modulator feedback loop by utilizing a capacitive summation stage. For given gain, resolution, and bandwidth requirements, the delta sigma modulator architecture achieves reduced power consumption by advantageously reducing the number of nodes in the system that require a high dynamic range. Additionally, the delta sigma modulator has very high input impedance such that the input of the delta-sigma modulator can be connected directly to a high impedance signal source, without the need for a front-end pre-amplifier stage, or the like.

Growing community of inventors

Palo Alto, CA, United States of America

Man-Chia Chen