Marvell International Limited

Apple Inc.

Marvellworld Trade Ltd.

Maxim Integrated Products, Inc.

Tao Shui

Yonghua Song

Hao Zhou

Dennis Sinitsky

Jie Jiang

Song Chen

Junshi Qiao

Haiqing Zhang

Brian Richards Land

Shafiq M Jamal

Nilay D Jani

Han Bi

Bingkun Yao

Na Huang

Pei Wang

Joseph W Colosimo

Saeed Mohammadi

Jianmin Guo

Yongxu Wang

Wei Hou

Yihui Li

Hong Xue

Yexin Chen

Dechao Meng

Yiran Li

An optical sensor can be multiplexed for different clients/features including estimating information or characteristics of a user's physiological signals. Additionally, the clients/features can include estimating information or characteristics independent from a user's physiological signals. As the number of clients increase and/or as the requirements for the clients increase, flexibility can be provided to accommodate the various clients. Parallelization of the optical sensor can be used to improve performance as the number of clients increase. For example, the hardware and software architecture can assemble patterns of time slots that measure all desired light paths for the multiple clients and distribute the corresponding measurements to each client according to the client requests. In some examples, the scanning sequence can be represented by frames including slots associated with multiple clients to compress the representation for larger or more complex scan sequences.

System and method for multiplexing an optical sensor

Detecting user contact with one or more electrodes of a physiological signal sensor can be used to ensure physiological signals measured by the physiological signal sensor meet waveform characteristics (e.g., of a clinically accurate physiological signal). In some examples, a mobile and/or wearable device can comprise sensing circuitry, stimulation circuitry, and processing circuitry. The stimulation circuit can drive one or more stimulation signals on one or more electrodes, the resulting signal(s) can be measured (e.g., by the sensing circuitry), and the processing circuitry can determine whether a user is in contact with the electrode(s). Additionally or alternatively, in some examples, mobile and/or wearable device can comprise saturation detection circuitry, and the processing circuitry can determine whether the sensing circuitry is saturated.

Contact detection for physiological sensor

An earbud may have a housing with an ear portion and an elongated out-of-ear portion that protrudes away from the ear portion. A speaker may be aligned with a speaker port in the ear portion and may emit sound for a user. Audio playback functions and other operations may be controlled using a controller in the earbud. The controller may gather capacitive sensor data and other data and may use this data in identifying an operating mode of the earbud. Using information such as whether the earbud is in an in-ear state or an out-of-ear state or other sensor data, the controller may take actions such as pausing or resuming audio playback or adjusting playback volume. The capacitive sensor data can be gathered using capacitive sensing electrodes located on the ear portion and the stalk portion of the earbud.

Earbud devices with capacitive sensors

This relates to methods and apparatus for mitigating effects of the presence of RF communication signals. In some examples, non-linearity and rectification of the RF communication signals can become rectified in sensor circuitry such that spectral components of a frame or sub-frame timing of the RF communication signals can be aliased into the sensor circuitry output within a bandwidth of interest. In some examples, a notch filter can be employed to remove the aliased RF communication signals from the sensor output. In some examples, a sampling rate used for sampling the user's physiological signals can be generated such that the sampling of the sensor is synchronous with the RF communication signals. In some examples, the sampling rate for the sensor can be generated as an integer multiple or integer submultiple of the frame or sub-frame timing of the RF communication signals.

Removing RF interference through scan rate locking

Aspects of the disclosure provide a touch panel having an electrode array. The electrode array includes first electrodes arranged on a first layer, each first electrode patterned to include a plurality of sequentially connected first electrode elements that are generally shaped as elongated polygons, and second electrodes arranged on a second layer, each second electrode patterned to include a plurality of sequentially connected second electrode elements that are generally shaped as elongated polygons, wherein the first electrodes on the first layer and the second electrodes on the second layer are arranged over one another so as to form an interlocking pattern.

Touch panel and touch detection circuit

System and methods are provided for touch detection. The system includes: a sensing capacitive network configured to generate a touch-sensing signal based at least in part on a touch panel capacitance; an internal capacitive network configured to generate an input signal based at least in part on a predetermined internal capacitance; a comparative network configured to compare the touch-sensing signal with a reference signal to generate a first comparison result and compare the input signal with the reference signal to generate a second comparison result; and a signal processing component configured to generate a detection result to indicate whether a touch event occurs on the touch panel based at least in part on the first comparison result and the second comparison result.

Systems and methods for capacitive touch detection

A resonant element driver circuit includes a NMOS transistor and a PMOS transistor that are configured to drive a resonant element. The resonant element driver circuit includes biasing circuitry that is configured to bias the PMOS transistor. The biasing circuitry receives a reference signal that is used to set the biasing on the PMOS transistor. The resonant element driver further includes mirror circuitry that tracks current flowing through the NMOS and PMOS transistors.

Class-AB XTAL circuit

Aspects of the disclosure process an amplifier circuit. The amplifier circuit includes an input stage, an intermediate stage, an output stage and a detecting and controlling circuit. The input stage is configured to receive an electrical signal for amplification. The intermediate stage is configured to amplify with an adjustable gain. The output stage is configured to drive an audio output device in response to the amplified electrical signal. The detecting and controlling circuit is configured to detect a current for driving the audio output device, and adjust the gain of the intermediate stage based on the current to compensate for a pole change of the amplifier circuit due to a change of the current.

Headphone amplifier

In one embodiment, an apparatus includes a first supply voltage and a second supply voltage. Level shifter circuitry is configured as a first voltage battery to shift a first voltage and a second voltage battery to shift a second voltage. A first circuit receives the shifted first voltage and sets a third voltage, and receives the shifted second voltage and sets a fourth voltage. The shifted first voltage is greater than the first supply voltage and the shifted second voltage level is less than the second supply voltage. A second circuit sets a fifth voltage and a sixth voltage. The fifth voltage follows the third voltage and the sixth voltage following the fourth voltage.

Voltage reference buffer using voltage battery level shifter

New and highly stable oscillators are disclosed. Such an oscillator may include a first capacitor electrically connected to a first charging switch and a first discharging switch, a second capacitor electrically connected to a second charging switch and a second discharging switch, a first chopping circuit having a first input electrically connected to the first capacitor and a second input electrically connected to a reference voltage, a second chopping circuit having a first input electrically connected to the second capacitor and a second input electrically connected to the reference voltage, a first comparator having a first input electrically connected to a first and second output of the first chopping circuit, a second comparator having a first input electrically connected to a first and second output of the second chopping circuit, and control circuitry having a first input electrically coupled to an output of the first comparator and a second input electrically connected to an output of the second comparator.

Precision oscillator with temperature compensation

Aspects of the disclosure provide a circuit. The circuit includes a signal amplifying circuit coupled with a crystal component of a natural frequency to form a crystal oscillator, and a signal generator circuit configured to generate a signal with an energy distribution about the natural frequency, and to provide the signal to the crystal oscillator to assist the crystal oscillator to begin oscillating.

Method and apparatus for starting up oscillation

In accordance with the teachings described herein, systems and methods are provided for a time-interleaved pipeline analog to digital converter. An example pipeline analog to digital converter may include passive sampling circuits and a multiplying digital to analog converter circuit. A first passive sampling circuit includes an input terminal coupled to an analog input signal, and outputs a first sample voltage that is responsive to the analog input signal. A second passive sampling circuit includes an input terminal coupled to the analog input signal, and outputs a second sample voltage that is responsive to the analog input signal. The first and second passive sampling circuits are clocked such that the first sample voltage and the second sample voltage are time-interleaved. A multiplying analog to digital converter (MDAC) circuit receives the time-interleaved first and second sample voltages from the first and second passive sampling circuits and processes the time-interleaved first and second sample voltages to generate a residue output voltage.

Low power high speed pipeline ADC

A beta enhancement circuit includes a current source connected in series with a transistor between two voltage supply lines. In an embodiment, the voltage supply lines are configured for connection to a power source and ground potential. A resistor device is connected between a control terminal of the transistor device and one of voltage supply lines. A value for the resistor device is selected based on one or more process dependent parameters of the transistor.

Growing community of inventors

Cupertino, CA, United States of America

Tao Shui