Abstract: Systems, methods, and devices are provided to reduce noise present in sensing circuits used for calibrating light emitting diodes (e.g., organic light emitting diodes) in electronic display devices. Such a system may include a display that renders image data using self-emissive pixels. Values on the pixels may be sensed using a current source that outputs a current and a comparator that receives the current. The comparator changes states when a voltage signal output by the capacitor crosses a first threshold voltage or a second threshold voltage. A controller receives a first time when the comparator component changes states based on the voltage signal, receives a second time when the comparator component changes states based on the voltage signal, determines a current value based on the first time and the second time, and calibrates a pixel based on the current value.

Abstract: An integrated Silicon-OLED display and touch sensor panel is disclosed. The integrated Silicon-OLED display and touch sensor panel can include a Silicon substrate, an array of transistors, one or more metallization layers, one or more vias, an OLED stack, color filters, touch sensors, and additional components and circuitry. Additional components and circuitry can include an electrostatic discharge device, a light shielding, a switching matrix, one or more photodiodes, a near-infrared detector and near-infrared color filters. The integrated Silicon-OLED display and touch sensor panel can be further configured for near-field imaging, optically-assisted touch, and fingerprint detection. In some examples, a plurality of touch sensors and/or display pixels can be grouped into clusters, and the clusters can be coupled to a switching matrix for dynamic change of touch and/or display granularity.

Abstract: A sense amplifier can be designed with a series variable resistance circuit to dynamically adjust an input resistance in series with the sense amplifier for stability during the different operating modes. In some examples, a switchable resistor can be switched into the input path of the sense amplifier for stability when required by increased capacitive loading of the sense electrodes, and can be switched out of the input path of the sense amplifier when unnecessary for stability. In some examples, an adjustable resistor can be coupled to and in series with the input of the sense amplifier. The resistance of the adjustable resistor can be tuned to stabilize the sense amplifier during operating modes having increased capacitive loading from the sense electrodes and can be minimized when additional input resistance is unnecessary for stability.

Abstract: A charge pump that can be configured to operate in a first mode and a second mode is disclosed. The charge pump can comprise a charging capacitor coupled to a first node and configured to transfer a first DC voltage to the first node. The charge pump can also comprise a first output node and a second output node coupled to the first node. During the first mode, the first output node can be configured to output a second DC voltage based on the first DC voltage, and the second output node can be configured to output a third DC voltage based on the first DC voltage. During the second mode, the first output node can be configured to output the second DC voltage, and the second output node can be configured to output an AC voltage, the AC voltage being offset by the third DC voltage.

Abstract: A touch controller is disclosed. The touch controller can include sense circuitry configured to sense, during a self-capacitance portion of a touch frame, first one or more self-capacitances associated with a first plurality of touch pixels on a touch sensor panel, and sense, during a mutual capacitance portion of the touch frame, first one or more mutual capacitances associated with the first plurality of touch pixels. A touch processor can be configured to, based on the first one or more self-capacitances and the first one or more mutual capacitances, sense a single touch event associated with the touch frame.

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: 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: 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: Electrode configurations for reducing wobble error for a stylus translating on a surface over and between electrodes of a touch sensor panel are disclosed. In some examples, electrodes associated with a more linear signal profile are correlated with lower wobble error. In some examples, electrodes can have projections which can interleave with projections of adjacent electrodes. In some configurations, projections of adjacent electrodes can be interleaved in one-dimension; in other configurations, projections of adjacent electrodes can be interleaved in two-dimensions. In some configurations, the width and length of one or more projections in an electrode can be selected based on a desired signal profile for that electrode.

Abstract: Systems and methods are provided for adjusting and displaying image data to account for variable common voltage error across separate common electrode sub-plates. The image data may be adjusted based on a common mode common voltage error on a common voltage line coupled to more than one different common electrode sub-plate. Each common electrode sub-plate may carry a common voltage that varies depending on values of the image data programmed to pixels associated with that common electrode sub-plate.

Abstract: Systems and methods are provided for adjusting and displaying image data to account for variable common voltage error across separate common electrode sub-plates. The image data may be adjusted based on a common mode common voltage error on a common voltage line coupled to more than one different common electrode sub-plate. Each common electrode sub-plate may carry a common voltage that varies depending on values of the image data programmed to pixels associated with that common electrode sub-plate.

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: A charge pump that can be configured to operate in a first mode and a second mode is disclosed. The charge pump can comprise a charging capacitor coupled to a first node and configured to transfer a first DC voltage to the first node. The charge pump can also comprise a first output node and a second output node coupled to the first node. During the first mode, the first output node can be configured to output a second DC voltage based on the first DC voltage, and the second output node can be configured to output a third DC voltage based on the first DC voltage. During the second mode, the first output node can be configured to output the second DC voltage, and the second output node can be configured to output an AC voltage, the AC voltage being offset by the third DC voltage.

Abstract: A system is disclosed. The system can comprise drive circuitry included in a first component of the system, the drive circuitry configured to drive a first touch electrode on a touch sensor panel. The system can also comprise a driving line configured to couple an output of the drive circuitry to the first touch electrode. The system can also comprise a feedback line configured to couple the output of the drive circuitry to an input of the drive circuitry, wherein a first end of the feedback line is coupled to the input of the drive circuitry at the first component, and a second end of the feedback line is configured to be coupled to the output of the drive circuitry at a second component, different from the first component, of the system.

Abstract: A sense amplifier can be designed with a series variable resistance circuit to dynamically adjust an input resistance in series with the sense amplifier for stability during the different operating modes. In some examples, a switchable resistor can be switched into the input path of the sense amplifier for stability when required by increased capacitive loading of the sense electrodes, and can be switched out of the input path of the sense amplifier when unnecessary for stability. In some examples, an adjustable resistor can be coupled to and in series with the input of the sense amplifier. The resistance of the adjustable resistor can be tuned to stabilize the sense amplifier during operating modes having increased capacitive loading from the sense electrodes and can be minimized when additional input resistance is unnecessary for stability.

Abstract: A radio transceiver is disclosed. The transceiver comprises an integrated circuit. The integrated circuit comprises a transmit path; a first switch coupled in series with the output of the transmit path; a receive path; and a second switch coupled as a shunt with the input of the receive path. The transceiver further comprises a plurality of external matching networks coupled to the transmit and receive paths of the integrated circuit to ensure minimal loading from one path to the other. The transceiver also comprises a shared balun for converting differential signals from the plurality of external matching networks to single ended signals; and an antenna to interface with the single ended signals. A method and system in accordance with an embodiment enables tying together the transmit path and the receive paths of a radio transceiver without the need for an external T/R switch.

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.