Abstract: A capacitance sensing system may include a first selection circuit that couples N electrodes of a first electrode set to a capacitance sense circuit; and a second selection circuit that couples M electrodes of a second electrode set, substantially simultaneously, to a signal generator circuit as a group to induce current in the N electrodes by mutual capacitance between the M and N electrodes; wherein N is at least one, and M>N.

Abstract: A method and apparatus receive a plurality of signal values, the plurality of signal values responsive to an input object. The method and apparatus calculate at least one signal ratio value using the plurality of signal values and determine a position of the input object using the at least one signal ratio value.

Abstract: A method, apparatus, and system to detect a self-capacitance activation in view of a self-capacitance measurement of a first electrode. The method, apparatus, and system further to detect a mutual capacitance activation in view of a mutual capacitance measurement of a pair of electrodes, and to determine the presence of water proximate to the capacitive button when the self-capacitance activation is false and the mutual capacitance activation is true. The capacitive button is disposed on a substrate.

Abstract: Apparatus and methods of active stylus to host device data transmitting are described. One method receives, at a stylus, an indication that a host device is performing a first coordinate measurement operation to determine a coordinate of the stylus proximate to a capacitive sense array of the host device. The set of coordinate measurement operations includes a first measurement operation of a first set of electrodes of the capacitive sense array and a second measurement operation of a second set of electrodes of the capacitive sense array. While the host device is performing the set of coordinate measurement operations, the stylus transmits a data packet of stylus data to the host device. In particular, the stylus transmits a first bit of the data packet during the first measurement operation and transmits a second bit of the data packet during the second measurement operation.

Abstract: A method and apparatus for reducing influence of noise for touch screen controllers employing noise listening synchronization, delay lines, filtering and sensing selected touch screen electrodes.

Abstract: Apparatuses and methods of input attenuator circuits are described. One sensing circuit includes an attenuator circuit to receive a signal from an electrode of a sense array. The attenuator circuit is configured to attenuate input current of the signal. The attenuator circuit includes an attenuation matrix including an input terminal to receive the signal and multiple resistors. The attenuation matrix is configured to split the input current into an output current of the attenuation signal on a first output terminal and a second output current on a second output terminal. The attenuation matrix is to output the attenuated signal on the first output terminal to an integrator of the sensing circuit. The attenuator circuit also includes a buffer coupled between the attenuation matrix and the integrator. The buffer is configured to maintain a substantially same voltage at the first output terminal and the second output terminal.

Abstract: A capacitance sensing system can include a noise detector coupled to a capacitance sensing network that generates a noise detect signal in response to noise; a delay circuit coupled to generate at least two different delayed sense signals in response to outputs from the capacitance sensing network; and a switch circuit that selectively outputs one of the delayed sense signals in response to the noise detect signal. Particular embodiments can include selectively discarding discrete analog samples of a capacitance signal when noise is detected in such a sample.

Abstract: Apparatuses and methods of input attenuator circuits are described. One sensing circuit includes an attenuator circuit to receive a signal from an electrode of a sense array. The attenuator circuit is configured to attenuate input current of the signal. The attenuator circuit includes an attenuation matrix including an input terminal to receive the signal and multiple resistors. The attenuation matrix is configured to split the input current into an output current of the attenuation signal on a first output terminal and a second output current on a second output terminal. The attenuation matrix is to output the attenuated signal on the first output terminal to an integrator of the sensing circuit. The attenuator circuit also includes a buffer coupled between the attenuation matrix and the integrator. The buffer is configured to maintain a substantially same voltage at the first output terminal and the second output terminal.

Abstract: Apparatuses and methods of frequency-response calculation are described. One method measures a charge on an electrode of a touch panel by a capacitance-sensing circuit of a processing device. The processing device measures a frequency response of the touch panel and selects an operating frequency of the touch panel in view of the frequency response.

Abstract: A device comprising a body comprising an elongated housing with at least a first conductive tip formed at a distal end and at least one sense electrode on the body; a capacitance sense circuit disposed within the housing and configured to sense a capacitance of the sense electrode to generate a proximity result in response to contact with a human body; and a signal generator circuit disposed within the housing and configured to activate a position signal in response to the proximity result, the position signal being driven at the tip of the device

Abstract: A device comprising a body comprising an elongated housing with at least a first conductive tip formed at a distal end and at least one sense electrode on the body; a capacitance sense circuit disposed within the housing and configured to sense a capacitance of the sense electrode to generate a proximity result in response to contact with a human body; and a signal generator circuit disposed within the housing and configured to activate a position signal in response to the proximity result, the position signal being driven at the tip of the device.

Abstract: A parallel pipelining method of operation of a touch sense controller for processing data into a touch map is disclosed. A current full scan of response signals to at least one excitation of a touch sense array is received using a first thread of a processing device. The current full scan of response signals is processed using a second thread of the processing device to render a touch map corresponding to the touch sense array. A next full scan of response signals is received using the first thread. Receiving the next full scan and processing the current full scan are performed substantially simultaneously.

Abstract: A technique for providing reliable position calculations for conductive inputs at the edges of a touch-sensitive array is disclosed. A matrix of sensors is completed using virtual sensors or nodes, allowing for a closer approximation of position of a conductive object. The matrix may be defined by a center point or sensor and a number of surrounding nodes or sensors.

Abstract: A method and apparatus for scanning a first set of electrodes of a capacitive sense array using a first sensing mode to identify a presence of an object in proximity to the capacitive sense array, where scanning using the first sensing mode identifies objects not in physical contact with the capacitive sense array. The first set of electrodes is scanned using a second sensing mode to determine a location of the object in relation to the capacitive sense array, where rescanning using the second sensing mode determines locations of objects in physical contact with the capacitive sense array.

Abstract: Capacitive touch sensors and touchscreen data processing methods are provided. In one embodiment, the method includes sequentially integrating and converting charge from each of a plurality of sensing capacitors in an array to digital data, the digital data including sample values corresponding to a measured capacitance for each of the plurality of sensing capacitors. Noise is then separated from useful information by filtering the sample values on a sample-by-sample basis. Finally, the filtered sample values are summed and a position of at least one contact on the array determined using the filtered capacitance values. Other embodiments are also provided.

Abstract: An apparatus includes a transmission system configured to transmit a drive signal to a touch screen device. The apparatus also includes a reception system configured to integrate an output signal received from a touch screen device in response to the drive signals and to filter the integrated output signal to suppress noise in the output signal, wherein the reception system is configured to integrate the output signal for a period of time that is less than or equal to a signal period corresponding to the drive signal.

Abstract: A method and apparatus receive a plurality of signal values, the plurality of signal values responsive to an input object. The method and apparatus calculate at least one signal ratio value using the plurality of signal values and determine a position of the input object using the at least one signal ratio value.

Abstract: A method includes powering multiple touch sensors using DC power derived from an AC power signal; monitoring the AC power signal and producing from the AC power signal a trigger signal that occurs repeatedly at a predetermined point in a cycle of the AC power signal; and initiating a scan of the touch sensors when the trigger signal occurs during each cycle of the AC power signal.

Abstract: A capacitive sensor includes a switching capacitor circuit, a comparator, and a charge dissipation circuit. The switching capacitor circuit reciprocally couples a sensing capacitor in series with a modulation capacitor during a first switching phase and discharges the sensing capacitor during a second switching phase. The comparator is coupled to compare a voltage potential on the modulation capacitor to a reference and to generate a modulation signal in response. The charge dissipation circuit is coupled to the modulation capacitor to selectively discharge the modulation capacitor in response to the modulation signal.

Abstract: A capacitive sensor includes a switching capacitor circuit, a comparator, and a charge dissipation circuit. The switching capacitor circuit reciprocally couples a sensing capacitor in series with a modulation capacitor during a first switching phase and discharges the sensing capacitor during a second switching phase. The comparator is coupled to compare a voltage potential on the modulation capacitor to a reference and to generate a modulation signal in response. The charge dissipation circuit is coupled to the modulation capacitor to selectively discharge the modulation capacitor in response to the modulation signal.