Apple Inc.

Applied Micro Circuits Corporation

Macom Connectivity Solutions, LLC

Moshe H Malkin

Vivek Pant

Manu Agarwal

Tarun Gupta

Shahrooz Shahparnia

Brandon R Garbus

John Greer Elias

Sumant Ranganathan

Ray Ling Chang

Alexandre Gourevitch

Michael F Jean

Arash Mehrabi

Alin I Gherghescu

Jose V Santos Martinez

Atul A Salvekar

Brian D Mariner

Benjamin M Oztalay

Bo Zhou

Andrew H Jones

Noise introduced into touch sensor panel measurements, for example, from display data lines of a display device proximate to the touch sensor panel, can be reduced. In some examples, touch sensing operations and display operations can be synchronized. For example, touch sensing scans (or scan steps) can begin with the rising edge of a display line synchronization signal. Additionally, the display noise can be characterized for the system. Display noise characterization and timing synchronization can be used to discard touch sensing samples including display noise injected into the touch sensor panel that may be synchronized to the display data line synchronization signal. In some examples, a window can be generated based on the characterized display noise, and the window can be applied to annihilate display noise. The application of the window can be time-dependent to account for offsets between the occurrence of the display noise and the touch sensing operation.

Display line aware noise mitigation for touch screens

A wearable electronic device comprises a multi-segment force sensor and a signal aggregator. The sensor comprises at least a first segment and a second segment connected to a flexible substrate material. A first portion of the substrate material (to which the first segment is attached) and a second portion of the substrate material (to which the second segment is attached) collectively wrap at least partially around a portion of an individual's body. The signal aggregator receives respective signals indicative of forces applied by an individual to the segments, and causes a representation of the respective signals to be transmitted to an application processing engine.

Segmented force sensors for wearable devices

Errors in touch signals due to grip and finger coupling to routing traces can be compensated. In some examples, reference traces can be provided to measure a signal contribution from a user's grip to routing traces. In some examples, shielding electrodes can be provided to reduce fringing field coupling between a user's grip and routing traces that are missing a neighboring trace. In some examples, a global correction for finger to trace coupling can be performed based on stored matrices that characterize cross-coupling between touch sensor electrodes in a touch sensor electrode array. In some examples, a determined touch location can be used to apply localized matrix correction to a subset of touch sensor electrodes in the touch sensor electrode array. In some examples, correction for multiple touch locations can be corrected in a specified order to avoid compensating for crosstalk effects of a single touch sensor electrode multiple times.

Compensation techniques for grip and finger coupling to routing traces in a touch sensor panel

Improved sensing can include modified sampling and/or processing to improve performance against noise due to environmental variations and interference. In some examples, improved interference rejection can be achieved by sampling a sensor multiple times during settled periods. In some examples, the excitation signal and sampling window can be dynamically adjusted to satisfy drift and/or interference specifications based on various operating conditions or the operating environment. In some examples, drift performance can be traded off to improve interference performance. In some examples, improved immunity to environmental variations can be achieved by equalizing sensor outputs in accordance with characterization of the sensing system. In some examples, improved performance can be achieved by sampling the sensor continuously and using an optimized window function to improve performance against noise.

Drift invariant processing

A wireless power transmitting device transmits wireless power signals modulated at a given power frequency to a wireless power receiving device using a wireless power transmitting coil. The wireless power receiving device may transmit data signals to the wireless power transmitting device. The wireless power transmitting device may include a data receiver that is coupled to the wireless power transmitting coil and that receives the transmitted data. The data receiver may include an input stage, bandpass filter circuitry, demodulator circuitry, and a data stream combiner. The data receiver may further include a power supply noise cancellation circuit. The power supply noise cancellation circuit may include an input stage, a baseband filter, a window filter, a down-sampler, and a difference filter. The power supply noise cancellation circuit may be coupled to the data stream combiner and is configured to mitigate power supply noise interference in the received data.

Wireless charging device with multi-tone data receiver and active power supply noise cancellation circuitry

A wireless power transmitting device transmits wireless power signals to a wireless power receiving device using a wireless power transmitting coil. The wireless power receiving device may transmit data packets to the wireless power transmitting device. The wireless power transmitting device may include a data receiver that is coupled to the wireless power transmitting coil and that receives the transmitted data packets. The data receiver may be configured to demodulate the received data packets. The data packets may include at least preamble bits, start bits, and data bits encoded as biphase half-bit signals in accordance with a predefined wireless power transfer protocol. During demodulation, the receiver may perform preamble detection, start bit detection, and data bit detection by comparing the input signals to corresponding reference patterns using a maximum likelihood sequence detection scheme. Phase recovery may be employed throughout to help provide immunity to phase change.

Methods and apparatus for performing demodulation using maximum likelihood sequence matching in a wireless charging device

Quasi-continuous-time sampling of discrete-time sampled signals

A wireless power transmitting device transmits wireless power signals modulated at a given power frequency to a wireless power receiving device using a wireless power transmitting coil. The wireless power receiving device may transmit data signals to the wireless power transmitting device. The wireless power transmitting device may include a data receiver that is coupled to the wireless power transmitting coil and that receives the transmitted data. The data receiver may include an input stage, bandpass filter circuitry, demodulator circuitry, and a data stream combiner. The bandpass filter circuitry may include at least two bandpass filter circuits for passing through signals at the power frequency and some harmonic of the power frequency. The demodulator circuitry may extract amplitude and phase information from the bandpass filtered signals and to generate multiple demodulated data streams. The data stream combiner may correlate the demodulated data streams and combine the correlated data streams.

Wireless charging device with multi-tone data receiver

Position-based sensing methods and systems can be used to transmit data from an input device to a touch-sensitive device. For example, the touch sensing system may perform one or more coarse input device sub-scans to determine a coarse location of the input device. The coarse location can be used to select one or more touch sensors (or sensor channels) to sample for decoding data encoded in the stimulation signals from the input device. During one or more fine input device sub-scans, the touch sensing system can determine a fine location of the input device and decode the data from the input device sampled from the selected touch sensors (or sensor channels).

Position-based stylus communication

A touch sensing system can demodulate sensor data using a dynamically adjusted demodulation waveform and/or demodulation window. The demodulation waveform and/or demodulation window can be dynamically adjusted to account for dynamically changing noise in a touch sensing system. The system can dynamically adjust the demodulation window based on noise measured by the touch sensing system to generate an optimized or otherwise noise-tailored window to suppress detected noise. In some examples, the noise measured by the touch sensing system can be sampled from sense channels localized to a detected touch.

Dynamic adjustment of demodulation waveform

Various embodiments provide systems and methods for performing clock recovery on a received signal using a split loop architecture. A split loop timing recovery apparatus is provided comprising a first path configured for performing frequency offset tracking on a signal by adjusting a receiver clock frequency to match a remote transmitter frequency associated with the signal and a second path configured for tracking random jitter on the signal.

Split loop timing recovery

Techniques for calibrating interleaved analog-to-digital converter (ADC) arrays are presented. A transceiver comprises an ADC component comprising an array of interleaved sub-ADCs, and an auxiliary path associated with an auxiliary sub-ADC used to facilitate calibrating a sampling array by comparing the auxiliary path signal to signals of the sub-ADCs in the array. A calibration component employs a phase-interpolator and analog delay lines to adjust the auxiliary sub-ADC to enable the auxiliary sub-ADC to be lined up to any one of the sampling instants of the sampling array. The calibration component compares the auxiliary signal to sub-ADC signals, determines path differences between the sub-ADC paths based on the comparison results, and calibrates the sub-ADCs and sub-ADC paths to reduce the path differences to mitigate distortion in a digital stream produced from combining the digital substreams produced by the sub-ADCs in the array.

Calibration and tracking of receiver

Techniques for calibration of high-speed interleaved analog-to-digital converter (ADC) arrays are presented. A transceiver comprises an ADC component that comprises an array of sub-ADCs that can be interleaved to facilitate high-speed data communications. The ADC component processes signals received from a remote transmitter to facilitate recovering the received data. The transceiver can comprise a calibration component that determines transfer characteristics of the communication channel or medium between the transceiver and the remote transmitter, and the transfer characteristics of the remote transmitter to each of the sub-ADCs of the array, based on the recovered data. The calibration component calibrates sub-ADCs of the array to facilitate correcting sub-ADC path differences, based on the respective transfer characteristics, to facilitate mitigating distortions that would be caused by the path differences, wherein the calibration component can use channel estimation to determine the transfer functions of the sub-ADCs of the array.

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Menlo Park, CA, United States of America

Moshe H Malkin