Abstract: A device includes an analog to digital converter configured to convert voltages into a digital signal by sampling the voltages at a fixed sampling time; a first multiplier configured to multiply the digital signal with in-phase coefficients, the in-phase coefficients generated to produce a demodulated in-phase signal at a demodulation signal frequency; a first adder configured accumulate the demodulated in-phase signal to output in-phase magnitude values; a second multiplier configured to multiply the digital signal with quadrature coefficients, the quadrature coefficients generated to produce a demodulated quadrature signal at the demodulation signal frequency; and a second adder configured to accumulate the demodulated quadrature signal to output quadrature magnitude values.

Abstract: A device includes an analog to digital converter configured to convert voltages into a digital signal by sampling the voltages at a fixed sampling time; a first multiplier configured to multiply the digital signal with in-phase coefficients, the in-phase coefficients generated to produce a demodulated in-phase signal at a demodulation signal frequency; a first adder configured accumulate the demodulated in-phase signal to output in-phase magnitude values; a second multiplier configured to multiply the digital signal with quadrature coefficients, the quadrature coefficients generated to produce a demodulated quadrature signal at the demodulation signal frequency; and a second adder configured to accumulate the demodulated quadrature signal to output quadrature magnitude values.

Abstract: A device includes an analog to digital converter configured to convert voltages into a digital signal by sampling the voltages at a fixed sampling time; a first multiplier configured to multiply the digital signal with in-phase coefficients, the in-phase coefficients generated to produce a demodulated in-phase signal at a demodulation signal frequency; a first adder configured accumulate the demodulated in-phase signal to output in-phase magnitude values; a second multiplier configured to multiply the digital signal with quadrature coefficients, the quadrature coefficients generated to produce a demodulated quadrature signal at the demodulation signal frequency; and a second adder configured to accumulate the demodulated quadrature signal to output quadrature magnitude values.

Abstract: A touch screen controller identifies an island in a matrix of acquired touch data values. A first sharpness of the island is calculated and a second sharpness of the island is calculated if the calculated first sharpness is greater than a sharpness threshold. A dynamic strength threshold is then determined as a function of the second sharpness if a variance of the island is greater than a dynamic variance threshold. A determination is then made that the identified island is a valid stylus island if a peak strength of the island is greater than the dynamic strength threshold.

Abstract: The present disclosure is directed to a system and method to remove common mode noise projected onto a touch sensor array from a display. The system is configured to activate two rows of electrodes at the same time, while coupling remaining rows of electrodes to ground. A first one of the two activated rows is used for detection of a touch and a second one of the two activated rows is used to detect common mode noise from the display. The common mode noise detected by the second row is removed from signals received from a plurality of columns of the touch sensor array.

Abstract: Disclosed herein is a touch screen controller that calculates a variance of an island in acquired touch data values. Where the variance exceeds a variance threshold, the island is validated as a representing touch. Where the variance does not exceed the variance threshold, whether the island represents a touch or a hover is determined by calculating a sharpness by applying weights to nodes of the island, where neighboring nodes adjacent to a peak node are weighted less than non-neighboring nodes not adjacent to the peak node. An island strength threshold is determined as a function of a product of the variance and the sharpness. It is determined that the island represents a touch where a highest touch data value of the island is greater than the island strength threshold, and a hover where the highest touch data value of the island is less than the island strength threshold.

Abstract: A method of foreign matter rejection for multi-touch capacitive touch screens includes performing touch detection in both self-capacitance mode and mutual capacitance mode. By combining information from both modes, a distinction is identified between wanted touches, such as by a finger or stylus, and unwanted touches such as by foreign matter.

Abstract: Disclosed herein is a touch screen controller operable with a touch screen. The touch screen controller includes input circuitry configured to receive touch data from the touch screen, and processing circuitry. The processing circuitry is configured to identify an island in the touch data, determine whether a horizontal groove is present in the island, determine whether a vertical groove is present in the island, and determine whether a diagonal groove is present in the island. The processing circuitry determines the island to indicate a single elongated touch where a diagonal groove is present in the island but horizontal and vertical grooves are not present in the island.

Abstract: A touch screen controller identifies an island in a matrix of acquired touch data values. A first sharpness of the island is calculated and a second sharpness of the island is calculated if the calculated first sharpness is greater than a sharpness threshold. A dynamic strength threshold is then determined as a function of the second sharpness if a variance of the island is greater than a dynamic variance threshold. A determination is then made that the identified island is a valid stylus island if a peak strength of the island is greater than the dynamic strength threshold.

Abstract: The present disclosure is directed to a system and method to remove common mode noise projected onto a touch sensor array from a display. The system is configured to activate two rows of electrodes at the same time, while coupling remaining rows of electrodes to ground. A first one of the two activated rows is used for detection of a touch and a second one of the two activated rows is used to detect common mode noise from the display. The common mode noise detected by the second row is removed from signals received from a plurality of columns of the touch sensor array.

Abstract: An electronic device disclosed herein includes a touch screen controller to identify an island i.e., a matrix of acquired touch data values, the island including adjacent touch data values indicating a potential touch of a touch sensitive screen. A first sharpness of the island is calculated using a first normalization type and not a second normalization type. A second sharpness of the island is calculated using the first and second normalization types if the first sharpness is greater than the sharpness threshold. A dynamic variance threshold is determined as a function of the second sharpness. A dynamic strength threshold is determined as a function of the second sharpness if a variance of the island is greater than the dynamic variance threshold, and the island is determined to be a valid stylus island if the peak strength is greater than the dynamic strength threshold.

Abstract: The present disclosure is directed to a system and method to remove common mode noise projected onto a touch sensor array from a display. The system is configured to activate two rows of electrodes at the same time, while coupling remaining rows of electrodes to ground. A first one of the two activated rows is used for detection of a touch and a second one of the two activated rows is used to detect common mode noise from the display. The common mode noise detected by the second row is removed from signals received from a plurality of columns of the touch sensor array.

Abstract: Disclosed herein is a touch screen controller operable with a touch screen. The touch screen controller includes input circuitry configured to receive touch data from the touch screen, and processing circuitry. The processing circuitry is configured to identify an island in the touch data, determine whether a horizontal groove is present in the island, determine whether a vertical groove is present in the island, and determine whether a diagonal groove is present in the island. The processing circuitry determines the island to indicate a single elongated touch where a diagonal groove is present in the island but horizontal and vertical grooves are not present in the island.

Abstract: Disclosed herein is a touch screen controller that calculates a variance of an island in acquired touch data values. Where the variance exceeds a variance threshold, the island is validated as a representing touch. Where the variance does not exceed the variance threshold, whether the island represents a touch or a hover is determined by calculating a sharpness by applying weights to nodes of the island, where neighboring nodes adjacent to a peak node are weighted less than non-neighboring nodes not adjacent to the peak node. An island strength threshold is determined as a function of a product of the variance and the sharpness. It is determined that the island represents a touch where a highest touch data value of the island is greater than the island strength threshold, and a hover where the highest touch data value of the island is less than the island strength threshold.

Abstract: A method of foreign matter rejection for multi-touch capacitive touch screens includes performing touch detection in both self-capacitance mode and mutual capacitance mode. By combining information from both modes, a distinction is identified between wanted touches, such as by a finger or stylus, and unwanted touches such as by foreign matter.

Abstract: The present disclosure is directed to a system and method to remove common mode noise projected onto a touch sensor array from a display. The system is configured to activate two rows of electrodes at the same time, while coupling remaining rows of electrodes to ground. A first one of the two activated rows is used for detection of a touch and a second one of the two activated rows is used to detect common mode noise from the display. The common mode noise detected by the second row is removed from signals received from a plurality of columns of the touch sensor array.

Abstract: An electronic device disclosed herein includes a touch screen controller to identify an island i.e., a matrix of acquired touch data values, the island including adjacent touch data values indicating a potential touch of a touch sensitive screen. A first sharpness of the island is calculated using a first normalization type and not a second normalization type. A second sharpness of the island is calculated using the first and second normalization types if the first sharpness is greater than the sharpness threshold. A dynamic variance threshold is determined as a function of the second sharpness. A dynamic strength threshold is determined as a function of the second sharpness if a variance of the island is greater than the dynamic variance threshold, and the island is determined to be a valid stylus island if the peak strength is greater than the dynamic strength threshold.

Abstract: An electronic device may include a touchscreen having an array of finger touch sensitive areas, and a controller coupled to the touchscreen. The controller is configured to read touch values from the array of finger touch sensitive areas, and determine when the read touch values define a valid single finger touch pattern having lower touch values within adjacent higher touch values, and, if so, treating the read touch values as being representative of a single finger touch, and, if not, causing a finger separation determination.

Abstract: A capacitive sensing structure is formed from first electrically conductive sensor structures electrically coupled to each other in a first direction, and second electrically conductive sensor structures electrically coupled to each other in a second direction. Each first electrically conductive sensor structure includes a first diamond-shaped central region with electrically coupled first finger structures extending away therefrom. Each second electrically conductive sensor structure includes a second diamond-shaped central region with electrically conducting second finger structures extending away therefrom. Each second finger structure extends between two adjacent ones of the first finger structures. Floating structures may be included within an opening formed in the first diamond shaped central region. Floating structures may further be included between the first and second finger structures.

Abstract: A single ITO layer design for a touchscreen panel incorporates a matrix of sensor cells formed from a single ITO layer of capacitive sensor pads, sensor bars, force lines and sense lines. Columns of multiplexed force lines are connected to rows of sensor pads to form force trees such that the force line of the end pair of sensor pads has a wide track, with the force lines of each subsequent pair of sensor pads having a reduced track width. Disposed between the columns of force trees, the matrix of sensor cells also includes columns of sensor bars connected to control circuitry via sense lines. The control circuitry applies a signal to the force trees to generate capacitance between rows of sensor pads and adjacent sensor bars. The control circuitry senses changes in the capacitance and resolves the location of a user touch in the matrix of sensor cells.