Abstract: Systems and method of performing touch and force sensing in an electronic device. The device includes a cover and an array of touch-sensor electrodes disposed below the cover. The first array of electrodes may be configured to sense a touch on the cover using a capacitive sensing scheme. The device also includes a force-sensor drive electrode disposed below the first array of electrodes and a force-sensor sense electrode disposed below the force-sensor drive electrode. The force-sensor drive and sense electrode may be configured to sense a force on the cover. The device also includes a shared drive circuit having an output that is operatively coupled to the array of touch-sensor electrodes and the force-sensor drive electrode.

Abstract: An electronic display includes a display panel, which includes an array of pixels and a driver configured to activate and deactivate the emission of light from each of the pixels in the array. The electronic display also includes a panel driver configured to generate and transmit an emission interrupt signal to the driver, wherein the emission interrupt signal causes the driver to deactivate the emission of light from all pixels in the array for a set period of time prior to a refresh of a line of pixels in the array.

Abstract: Systems and processes for encoding and decoding touch signals output by a touch sensor are provided. In one example system, switching circuitry can be used to selectively couple each of the sense lines of a touch sensor to a positive terminal or a negative terminal of a sense amplifier based on the values of the elements of a matrix. The touch signals can be amplified and converted into digital form using a single sense amplifier and an ADC before being decoded using decoding circuitry. The decoding circuitry can decode the digital encoded touch signals by multiplying the digital encoded touch signals by each column of an inverse of the matrix used to encode the touch signals. The result of the decoding can be a set of signals that are representative of the touch signals output by the touch sensor.

Abstract: Systems and processes for stimulating a touch sensor panel using orthogonal frequencies are provided. In one example process, the drive lines of the touch sensor panel can be stimulated with stimulation signals having orthogonal frequencies. The orthogonal frequencies can be separated by a frequency that is inversely proportional to an integration time of the touch sensor panel. The touch signals generated in response to the stimulation signals can be amplified, converted into digital form, demodulated using the orthogonal frequencies, and integrated over the integration time. Integrating the demodulated signals over a length of time that is inversely proportional to the frequency spacing between the orthogonal frequencies reduces or eliminates interference in the touch signals caused by the stimulation signals having different frequencies.

Abstract: A self-capacitance touch screen. In some examples, the touch screen comprises a plurality of display pixels, a first display pixel of the plurality of display pixels including a first touch electrode of a plurality of touch electrodes, and a gate line coupled to the first display pixel, wherein the gate line is configured such that a voltage at the gate line substantially follows a voltage at the first touch electrode. In some examples, the gate line is coupled to a resistor, the resistor being configured to decouple the gate line from ground. In some examples, the gate line is coupled to an AC voltage source.

Abstract: Devices and methods for reducing display-to-touch crosstalk are provided. In or more examples, an electronic display panel may include a pixel. The pixel may include a pixel electrode, a common electrode, and a first transistor having a first source coupled to a data line, a first gate coupled to a gate line, and a first drain coupled to the pixel electrode. The pixel may also include a second transistor having a second source coupled to the common electrode, a second gate coupled to the gate line, and a second drain coupled to a common voltage source. The second transistor may be configured to cause a parasitic capacitance between the gate line and the second drain of the second transistor and to reduce an effect of a parasitic capacitance between the gate line and the first drain of the first transistor.

Abstract: An electronic device may be provided with wireless circuitry and a display. A display driver integrated circuit in the display may have a spectrum analyzer circuit. An antenna may monitor for wireless signals. The display driver integrated circuit may use the spectrum analyzer circuit to analyze the wireless signals and determine whether there is a potential for visible display artifacts. In the presence of conditions that can lead to display artifacts, the display driver integrated circuit may adjust a gate driver control signal. Adjustments to the gate driver control signal may be made using adjustable signal dividers. The adjustments to the gate driver control signal eliminate the visible display artifacts.

Abstract: A self-capacitive touch sensor panel configured to have a portion of both the touch and display functionality integrated into a common layer is provided. The touch sensor panel includes a layer with circuit elements that can switchably operate as both touch circuitry and display circuitry such that during a touch mode of the device the circuit elements operate as touch circuitry and during a display mode of the device the circuit elements operate as display circuitry. The touch mode and display mode can be time multiplexed. By integrating the touch hardware and display hardware into common layers, savings in power, weight and thickness of the device can be realized.

Abstract: Systems, methods, and devices to control a transistor to maintain one or more substantially constant characteristics while activated or deactivated are provided. One such system includes a transistor that receives an activation signal on a gate terminal to become activated during a first period and receives a deactivation signal on the gate terminal to become deactivated during a second period. The transistor receives an input signal on an input terminal during the first period and the second period. The input signal varies during the first period and during the second period. The transistor may have improved reliability (e.g., substantially constant on resistance RON) because a first difference between the input signal and the activation signal substantially does not vary during the first period and a second difference between the input signal and the deactivation signal substantially does not vary during the second period.

Abstract: A touch screen to reduce touch pixel coupling. In some examples, the touch screen can include a first display pixel and a second display pixel in a row of display pixels, where the first display pixel can be configurable to be decoupled from the second display pixel during at least a touch sensing phase of the touch screen. In some examples, the touch screen can include a display pixel having a first and a second transistor, where the second transistor can be electrically connected to a gate terminal of the first transistor, and can be diode-connected. In some examples, the touch screen can include two display pixels, each display pixel having two transistors, where two of the transistors can be electrically connected to a first gate line, and the remaining two transistors can be individually electrically connected to a second and third gate line, respectively.

Abstract: A display may receive image data to be displayed for a user of an electronic device. Display driver circuitry in the display may analyze the data to detect static data. The image data may contain static frames of data or static portions of a frame of data. In response to detection of static data, the display driver circuitry can take actions to avoid display damage due to burn-in effects. The display driver circuitry may reduce a peak luminance value associated with a peak luminance control algorithm, may reduce display brightness, may map image data to reduced brightness levels, or may take other actions to ensure that display pixels in the display are not damaged. Temperature information may be used in determining how to classify information as static data and in determining how significantly to reduce display pixel drive currents in response to the detection of static image data.

Abstract: Systems and methods for calibrating an electronic display to reduce or eliminate artifacts are provided. One method for reducing or eliminating artifacts may involve baking the operational—but not yet fully calibrated—electronic display to reduce stray charge on the electronic display.

Abstract: A wireless data processing device is described which periodically exits an unpowered state and transmits location data. For example, one embodiment of a wireless data processing device comprises: power circuitry for maintaining the wireless data processing device in a powered or unpowered state, the power circuitry causing the wireless data processing device to enter into an unpowered state responsive to user input; a timer to periodically power up the wireless device or portion thereof in response to reaching a predetermined time; a location services module determining a current location of the wireless data processing device using one or more specified location determination techniques; a transmit thread transmitting the current location of the wireless device over one or more specified communication channels; and the power circuitry powering down the wireless data processing device a second time after the current location has been transmitted.

Abstract: Systems and methods for testing a peripheral in accordance with a MIPI protocol are provided. A test system can test a peripheral by providing user-5 specified control over a test processor (which is substantially the same processor the peripheral will interface with when installed) to test, calibrate, or both test and calibrate the peripheral. The test processor can communicate with the peripheral according 10 to the MIPI protocol, thereby effectively providing an actual “in-device” environment for testing and/or calibrating the peripheral.

Abstract: A self-capacitance touch sensor panel including a plurality of touch electrodes and one or more sense circuits coupled to the touch electrodes. The touch sensor panel also includes at least one offset cancellation circuit coupled to at least one of the touch electrodes and configured to generate an offset cancellation signal to cancel an offset signal at the at least one touch electrode. In some examples, the offset cancellation signal can be an offset cancellation current to cancel an offset current. In some examples, the offset cancellation circuit comprises a variable resistor, and a magnitude of the offset cancellation current is based on a resistance of the variable resistor. In some examples, each touch electrode is coupled to an offset cancellation circuit. In other examples, a single offset cancellation circuit is shared by a plurality of touch electrodes.

Abstract: Setting a slew rate, e.g., a rising time or a falling time, of a scanning signal can be performed with a first operation, and a shunting resistance of the scanning line can be set with a second operation. A scanning system that scans a display screen, a touch screen, etc., can set a desired slew rate during a first period of time and can set a desired shunting resistance during a second period of time. A gate line system can sequentially scan gate lines to display an image during a display phase of a touch screen. The gate line system can, for example, increase the falling times of gate line signals. After the falling gate line signal has stabilized, for example, the gate line system can decrease the shunting resistance of the gate line.

Abstract: A wireless data processing device is described which periodically exits an unpowered state and transmits location data. For example, one embodiment of a wireless data processing device comprises: power circuitry for maintaining the wireless data processing device in a powered or unpowered state, the power circuitry causing the wireless data processing device to enter into an unpowered state responsive to user input; a timer to periodically power up the wireless device or portion thereof in response to reaching a predetermined time; a location services module determining a current location of the wireless data processing device using one or more specified location determination techniques; a transmit thread transmitting the current location of the wireless device over one or more specified communication channels; and the power circuitry powering down the wireless data processing device a second time after the current location has been transmitted.

Abstract: Systems, methods, and devices to control a transistor to maintain one or more substantially constant characteristics while activated or deactivated are provided. One such system includes a transistor that receives an activation signal on a gate terminal to become activated during a first period and receives a deactivation signal on the gate terminal to become deactivated during a second period. The transistor receives an input signal on an input terminal during the first period and the second period. The input signal varies during the first period and during the second period. The transistor may have improved reliability (e.g., substantially constant on resistance RON) because a first difference between the input signal and the activation signal substantially does not vary during the first period and a second difference between the input signal and the deactivation signal substantially does not vary during the second period.

Abstract: Systems and method of performing touch and force sensing in an electronic device. The device includes a cover and an array of touch-sensor electrodes disposed below the cover. The first array of electrodes may be configured to sense a touch on the cover using a capacitive sensing scheme. The device also includes a force-sensor drive electrode disposed below the first array of electrodes and a force-sensor sense electrode disposed below the force-sensor drive electrode. The force-sensor drive and sense electrode may be configured to sense a force on the cover. The device also includes a shared drive circuit having an output that is operatively coupled to the array of touch-sensor electrodes and the force-sensor drive electrode.

Abstract: An electronic device may be provided with wireless circuitry and a display. A display driver integrated circuit in the display may have a spectrum analyzer circuit. An antenna may monitor for wireless signals. The display driver integrated circuit may use the spectrum analyzer circuit to analyze the wireless signals and determine whether there is a potential for visible display artifacts. In the presence of conditions that can lead to display artifacts, the display driver integrated circuit may adjust a gate driver control signal. Adjustments to the gate driver control signal may be made using adjustable signal dividers. The adjustments to the gate driver control signal eliminate the visible display artifacts.