Abstract: Systems, methods, and devices detect defects in touch panels. Methods include scanning, using a designated integration window, a plurality of electrodes of a sensing device to obtain a plurality of measurements and determining a plurality of variance values for the plurality of electrodes based on the plurality of measurements, the plurality of variance values identifying variances in the plurality of measurements between adjacent sense locations of the sensing device. Methods also include determining if a defect is present in the sensing device based, at least in part, on a comparison of the plurality of difference values with the plurality of threshold values.

Abstract: Apparatuses and methods of quadrature modulation and compensation are described. One touch controller includes a receiver sensing channel to measure a sense signal and generate at least four samples per one period of the sense signal. The touch controller includes quadrature demodulation logic to determine phase information of the sense signal using the at least four samples per one period of the sense signal and processing logic to execute a compensation algorithm to compensate for a phase mismatch of the touch controller based on the phase information.

Abstract: Systems, methods, and devices improve the sensitivity of capacitive sensors. Devices may include an attenuator configured to receive an input from at least one sense electrode of a capacitive sensing device. The attenuator may be included in a sensing channel of a capacitive sensor. Devices may further include a signal generator coupled to an input of the attenuator. The signal generator may include one or more processors configured to generate a sinusoidal signal based, at least in part, on one or more noise characteristics of a scan sequence associated with one or more transmit electrodes of the capacitive sensing device, and provide the sinusoidal signal to the input of the attenuator.

Abstract: An apparatus includes a global baseliner circuit coupled with sensing channels of a sensing device. The global baseliner circuit has a signal generator to generate a rectified sinusoidal signal and a square wave having a frequency matching that of an excitation sinusoidal signal, and is to use the square wave to modulate the excitation sinusoidal signal provided at an output of the global baseliner circuit. A channel baseliner circuit is coupled between the global baseliner circuit and a sensing channel and that includes a switched capacitor coupled between the output of the global baseliner circuit and the sensing channel; a sigma-delta modulator coupled with the signal generator and to generate, from the rectified sinusoidal signal, a density-modulated bit stream; and a pair of AND gates to use the density-modulated bit stream and non-overlapping clock signals to generate outputs including density-modulated clock signals sent to switches of the switched capacitor.

Abstract: Systems, methods, and devices detect defects in touch panels. Methods include scanning, using a designated integration window, a plurality of electrodes of a sensing device to obtain a plurality of measurements and determining a plurality of variance values for the plurality of electrodes based on the plurality of measurements, the plurality of variance values identifying variances in the plurality of measurements between adjacent sense locations of the sensing device. Methods also include determining if a defect is present in the sensing device based, at least in part, on a comparison of the plurality of difference values with the plurality of threshold values.

Abstract: Systems, methods, and devices improve the sensitivity of capacitive sensors. Devices may include an attenuator configured to receive an input from at least one sense electrode of a capacitive sensing device. The attenuator may be included in a sensing channel of a capacitive sensor. Devices may further include a signal generator coupled to an input of the attenuator. The signal generator may include one or more processors configured to generate a sinusoidal signal based, at least in part, on one or more noise characteristics of a scan sequence associated with one or more transmit electrodes of the capacitive sensing device, and provide the sinusoidal signal to the input of the attenuator.

Abstract: Technology directed to low-emissions touch controller in in-cell touch display systems is described. One in-cell touch controller includes a signal generator circuit that is configured to generate a sense signal according to a sensing function, the sense signal including a windowed sinusoidal waveform. The controller generates a transition signal to transition the in-cell touch display between a display function and the sensing function. The controller drives the sense signal and the transition signal on common voltage (VCOM) layer of electrodes during a touch scanning interval. During a display function interval an integrated display driver is configured to drive a first signal on the VCOM layer of electrodes during a display function interval.

Abstract: Technology directed to low-emissions touch controller in in-cell touch display systems is described. One in-cell touch controller includes a signal generator circuit that is configured to generate a sense signal according to a sensing function, the sense signal including a windowed sinusoidal waveform. The controller generates a transition signal to transition the in-cell touch display between a display function and the sensing function. The controller drives the sense signal and the transition signal on common voltage (VCOM) layer of electrodes during a touch scanning interval. During a display function interval an integrated display driver is configured to drive a first signal on the VCOM layer of electrodes during a display function interval.

Abstract: Systems, methods, and devices improve the sensitivity of capacitive sensors. Devices may include an attenuator configured to receive an input from at least one sense electrode of a capacitive sensing device. The attenuator may be included in a sensing channel of a capacitive sensor. Devices may further include a signal generator coupled to an input of the attenuator. The signal generator may include one or more processors configured to generate a sinusoidal signal based, at least in part, on one or more noise characteristics of a scan sequence associated with one or more transmit electrodes of the capacitive sensing device, and provide the sinusoidal signal to the input of the attenuator.

Abstract: Technology directed to low-emissions touch controller in in-cell touch display systems is described. One in-cell touch controller includes a signal generator circuit that is configured to generate a sense signal according to a sensing function, the sense signal including a windowed sinusoidal waveform. The controller generates a transition signal to transition the in-cell touch display between a display function and the sensing function. The controller drives the sense signal and the transition signal on common voltage (VCOM) layer of electrodes during a touch scanning interval. During a display function interval an integrated display driver is configured to drive a first signal on the VCOM layer of electrodes during a display function interval.

Abstract: An apparatus includes a global baseliner circuit coupled with sensing channels of a sensing device. The global baseliner circuit has a signal generator to generate a rectified sinusoidal signal and a square wave having a frequency matching that of an excitation sinusoidal signal, and is to use the square wave to modulate the excitation sinusoidal signal provided at an output of the global baseliner circuit. A channel baseliner circuit is coupled between the global baseliner circuit and a sensing channel and that includes a switched capacitor coupled between the output of the global baseliner circuit and the sensing channel; a sigma-delta modulator coupled with the signal generator and to generate, from the rectified sinusoidal signal, a density-modulated bit stream; and a pair of AND gates to use the density-modulated bit stream and non-overlapping clock signals to generate outputs including density-modulated clock signals sent to switches of the switched capacitor.

Abstract: Systems, methods, and devices improve the sensitivity of capacitive sensors. Devices may include an attenuator configured to receive an input from at least one sense electrode of a capacitive sensing device. The attenuator may be included in a sensing channel of a capacitive sensor. Devices may further include a signal generator coupled to an input of the attenuator. The signal generator may include one or more processors configured to generate a sinusoidal signal based, at least in part, on one or more noise characteristics of a scan sequence associated with one or more transmit electrodes of the capacitive sensing device, and provide the sinusoidal signal to the input of the attenuator.

Abstract: Described herein are devices, methods, and systems that detect the presence of faults such as shorts and/or opens within a touch sensitive display panel. In one embodiment, a touch screen controller is disclosed, the touch screen controller comprising one or more receive channels, where each receive channel is configured to scan a corresponding group of sensors of a plurality of sensors. The touch screen controller may also comprise a plurality of multiplexers, each multiplexer configured to selectively couple a respective sensor of the plurality of sensors to a corresponding receive channel or a reference voltage. The touch screen controller may further comprise a processing device configured to detect one or more shorts based on DC current sensing. The touch screen controller may also detect one or more opens based on AC current sensing of each of the one or more receive channels.

Abstract: Technology directed to low-emissions touch controller in in-cell touch display systems is described. One in-cell touch controller includes a signal generator circuit that is configured to generate a sense signal according to a sensing function, the sense signal including a windowed sinusoidal waveform. The controller generates a transition signal to transition the in-cell touch display between a display function and the sensing function. The controller drives the sense signal and the transition signal on common voltage (VCOM) layer of electrodes during a touch scanning interval. During a display function interval an integrated display driver is configured to drive a first signal on the VCOM layer of electrodes during a display function interval.

Abstract: A method for detecting fingerprint spoof objects includes detecting a presence of the object at a fingerprint sensor and, in response to detecting the presence of the object, measuring a set of physical properties of the object based on one or more signals from a set of electrodes of the fingerprint sensor. The set of physical properties includes at least one of a subdermal compliance of the object and a surface adhesiveness of the object. The method further includes distinguishing the object as an actual finger or a spoof based on the one or more physical properties.

Abstract: A capacitance sensing device includes a transmit (TX) generator for generating a sequence of receive (RX) signals by applying each TX signal pattern in a sequence of TX signal patterns to a set of sensor electrodes. For each TX signal pattern in the sequence of TX signal patterns, and for each subset of three or more contiguous sensor electrodes of the set of sensor electrodes, the TX generator applies to the subset one of a first excitation signal and a second excitation signal. The plurality of subsets includes at least half of the sensor electrodes in the set of sensor electrodes. The capacitance sensing device also includes a sequencer circuit coupled with the TX generator. For each TX signal pattern in the sequence of TX signal patterns, the sequencer circuit determines a next subsequent TX signal pattern in the sequence based on a circular rotation of the TX signal pattern. The capacitance sensing device also includes a processing block coupled with the TX generator.

Abstract: A method for detecting fingerprint spoof objects includes detecting a presence of the object at a fingerprint sensor and, in response to detecting the presence of the object, measuring a set of physical properties of the object based on one or more signals from a set of electrodes of the fingerprint sensor. The set of physical properties includes at least one of a subdermal compliance of the object and a surface adhesiveness of the object. The method further includes distinguishing the object as an actual finger or a spoof based on the one or more physical properties.

Abstract: A system comprising a sensing device and a capacitive sense array configured to detect a presence of a passive touch object and a stylus where the capacitive sense array receives a transmit signal from the stylus via capacitive coupling. The system further comprising a processing device configured to determine the stylus location on the capacitive sense array based on the transmit signal and to synchronize the stylus to the capacitive sense array. A system further comprises a demodulation block to extract additional data that is modulated into the transmit signal by the stylus. The demodulation block is configured to extract the additional data by amplitude shift keying. The additional data comprises at least one of an applied force value of the stylus tip, a button status data, a battery status data, or a stylus acceleration data.

Abstract: A method for improving noise immunity of capacitive sensing circuit associated with a touch sense array is disclosed. The capacitive sensing circuit receives a response signal from a touch sense array. The capacitive sensing circuit measures a noise component of the response signal. When a level of noise of the noise component within a passband of the capacitive sensing circuit is greater than a threshold, the capacitive sensing circuit changes at least one parameter of capacitive sensing circuit to move the passband substantially outside the frequency spectrum of the noise component.

Abstract: Systems, methods, and apparatus for force sensor baseline calibration are disclosed herein. 1. Apparatus may include a force sensor configured to receive a plurality of force signals from a plurality of force sensitive elements, where the plurality of force signals is associated with a first touch at a first location of a sensing surface. The apparatus may include a touch sensor configured to receive a touch signal associated with the first touch. The apparatus may include processing logic coupled to the force sensor and the touch sensor, the processing logic being configured to determine a magnitude of a first component force associated with the first touch based, at least in part, on the plurality of force signals and the touch signal. The first component force may characterize a force applied by the first touch at the first location of the sensing surface.