Apple Inc.

Manu Agarwal

John Stephen Smith

Shahrooz Shahparnia

Hopil Bae

Kingsuk Brahma

Martin Paul Grunthaner

Moshe H Malkin

Sumant Ranganathan

Erno H Klaassen

Christian M Sauer

Brandon R Garbus

Jason C Hu

Cheng Kai Chen

Peter W Richards

Brijesh Tripathi

Kevin David Gibbs

Christopher P Tann

Erik Andrew Uttermann

Vivek Pant

Kevin J White

Dhaval Chandrakant Patel

Christopher J Butler

Alin I Gherghescu

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 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

A touch input device configured to detect stylus signals generated by an external stylus is provided. The touch input device includes a plurality of stylus signal detectors that receive at its input a combination of stylus receive channels that are combined in a manner to minimize noise while at the same time keeping the stylus signal strength uniform independent of the position of the stylus on the device.

Channel aggregation for optimal stylus detection

Disclosed herein are structures, devices, and methods for sensing physical parameters, such as strain in a surface, using resistance-based parameter sensors and current sensing. An applied strain can cause a differential change in one or more currents from two resistors configured in parallel in the sensor. Strain can be inferred from a ratio of the difference of the two currents to a sum of the two currents. These structures and methods can be adapted to measure strain or other parameters using an array of sensors, with common voltages applied to rows of the array, and currents being summed in column in the array so that fewer receivers are needed.

Row column architecture for strain sensing

A sensing device can be included in a display of an electronic device. Various techniques can be used to reduce display noise in the signals output from the sensing device. The techniques include the use of a filtering layer in a display stack, the use of a non-uniform sampling scheme, averaging together noise signal samples sampled over multiple display frames, and inverting a phase of the sampling of the noise signal over multiple display frames.

Reducing display noise in an electronic device

Several techniques for driving a force sensor to reduce common mode offset are disclosed. The force sensor can include at least one set of individual strain sensitive structures formed on or in a surface of a substrate. Each set of individual strain sensitive structures can include one or more strain sensitive structures. At least one external resistor is operably connected in series between a first output of one or more transmitter channels and at least one set of strain sensitive structures. The external resistor(s) effectively increases the resistances of the strain sensitive structures to reduce the common mode offset. Additionally or alternatively, one or more signal generators may be connected to one or more transmitter channels. Each signal generator is configured to produce one or more signals that is/are designed to reduce common mode offset.

Common mode control for a resistive force sensor

A force sensing device can be included in a display. Noise produced by various sources can be injected into the force signals produced by the force sensing device. Example noise sources include, but are not limited to, the display, Johnson or Thermal noise from the force sensing device, system noise, and magnetically-coupled or background noise produced by ambient light sources. A sampling scheme that includes one or more noise cancelling techniques can be employed to reduce the amount of noise in the force signals.

Reducing noise in a force signal in an electronic device

A system can include a display, a first device, and a second device all operatively connected to a controller. The first and second devices each use or share at least a portion of the display area. The controller is adapted to transmit during a pixel refresh time period of the display a first signal that is received by the first device. The first sync signal indicates a first time period in which a first operation can be performed in the first device. The controller is also adapted to transmit a second sync signal that is received by the second device indicating a second time period in which a second operation can be performed in the second device. The second time period can be during the pixel refresh time period or outside of the pixel refresh time period.

Operating multiple functions in a display of an electronic device

The disclosed embodiments relate to forming an area on a touchscreen which electrically isolates a portion of the viewable area of the touchscreen from a capacitive sensor associated with the touchscreen.

Mitigating noise in capacitive sensor

A touch sensitive device can be capable of detecting signals generated by a stylus and correcting the detected stylus signals for effects due to noise present on the device. In one example, signals are taken from one or more electrodes that are a pre-determined distance away from an electrode in which a stylus signal is detected. The pre-determined distance can be empirically determined such that a noise estimate can be generated such that the electrodes have a higher probability of containing only noise that is highly correlated to the noise present on a detected stylus signal. The generated noise estimate is then subtracted from a detected stylus signal to reduce the effect of noise on the stylus signal.

Noise correction for stylus applications on tablets and other touch devices

Systems and methods for accurately and precisely measuring the resistance of a resistive sensor of a matched resistive sensor pair disposed on opposite surfaces of a substrate. Certain embodiments include coupled each sensor of the matched resistive sensors to a thermally-isolated pair of reference resistors contained within an integrated circuit so as to form a Wheatstone bridge. A controller associated with the integrated circuit can adjust the resistance of the thermally-isolated pair of reference resistors until the ratio of resistances matches to the ratio of resistances between the sensors of the matched pair.

Systems and methods for measuring resistive sensors

Various timing schemes can be used to synchronizing display functions with touch and/or stylus sensing functions for devices including a variable refresh rate (VRR) display. In a continuous-touch mode, for example, extended blanking can result in frame judder due to mismatch or latency between reporting of sensing data and the display. To minimize these issues, sensing operations can reset to re-synchronize with the display operation, and unreported data from sensing scans can be discarded or ignored. In some examples, a display frame can be divided into two sub-frames, and a system can be configured to perform a touch sensing scan during the first sub-frame of a display frame. At the conclusion of extended blanking, the sensing operations can reset to re-synchronize with the display. The touch sensing scan can be completed in one intra-frame pause and can begin at the start of the display frame.

Timing scheme for touch screen supporting variable refresh rate

Noise in sensor panel measurements can be reduced using a common pixel correction algorithm. Noise can be introduced into touch or force sensor panel measurements, for example, by circuitry of a transmit (Tx) section or a receive (Rx) section coupled to one or more sensing nodes of a sensor panel. For example, a digital-to-analog converter in the transmit section or an analog-to-digital converter in the receive section can introduce low-frequency correlated noise. Additionally, transmit and receive sections can introduce uncorrelated noise into the system. Reference nodes, coupled between Tx and Rx sections, can sense correlated and uncorrelated noise from the Tx and Rx sections. The noise measured at reference nodes can be subtract from signals measured at other sensing nodes coupled to the same Rx channel. The measurement at the reference node can be scaled using a scaling parameter to account for differences between reference nodes and sensing nodes.

Common pixel correction for sensor panels

Synchronization of display functions and various touch, stylus and/or force sensing functions for devices including a variable refresh rate (VRR) display is disclosed. In some examples, touch, stylus and/or force sensing functions can be synchronized with display frames and a display refresh rate can be adjusted by extended blanking of the display for one or more display frames. In other examples, touch, stylus and/or force sensing functions can be synchronized with display sub-frames and a display refresh rate can be adjusted by extended blanking of the display for one or more display sub-frames. Pre-warning synchronization signals can be generated to prepare one or more scan controllers to implement the appropriate scan events during and after extended blanking periods. Latency between the scan results and the corresponding image on the display can be corrected in software and/or firmware by time-stamping scan results or by dropping scan results from uncompleted scans.

Growing community of inventors

Palo Alto, CA, United States of America

Manu Agarwal