Abstract: Fingerprint detection circuits with common mode noise rejection are described. The Fingerprint detection circuit includes a half-bridge circuit coupled to a receive (RX) electrode of an array of fingerprint detection electrodes and to a buried capacitance that is unalterable by the presence of a conductive object on the array. The fingerprint detection circuit may also include a listener electrode configured to enable common mode noise rejection through a differential input stage of a low noise amplifier (LNA).

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: An example system drives one or more transmit signals on first electrodes disposed in a first layer and propagating electrodes disposed in a second layer. The system measures a capacitance of sensors through a of second electrodes. Each second electrode crosses each first electrode to provide a plurality of discrete sensor areas, each discrete sensor area associated with a difference crossing and including a portion of at least one propagating electrode. Each second electrode is galvanically isolated from the first electrodes and the propagating electrodes.

Abstract: A fingerprint sensor-compatible overlay material which uses anisotropic conductive material to enable accurate imaging of a fingerprint through an overlay is disclosed. The anisotropic conductive material has increased conductivity in a direction orthogonal to the fingerprint sensor, increasing the capacitive coupling of the fingerprint to the sensor surface, allowing the fingerprint sensor to accurately image the fingerprint through the overlay. Methods for forming a fingerprint sensor-compatible overlay are also disclosed.

Abstract: A fingerprint sensor-compatible overlay material which uses anisotropic conductive material to enable accurate imaging of a fingerprint through an overlay is disclosed. The anisotropic conductive material has increased conductivity in a direction orthogonal to the fingerprint sensor, increasing the capacitive coupling of the fingerprint to the sensor surface, allowing the fingerprint sensor to accurately image the fingerprint through the overlay. Methods for forming a fingerprint sensor-compatible overlay are also disclosed.

Abstract: A method, apparatus, and system measure, at a first channel of a processing device, a first signal indicative of a touch object proximate to an electrode layer. The first signal includes a touch data component and a first noise component generated by a noise source. The method, apparatus, and system measure, at a second channel of the processing device, a second signal including a second noise component generated by the noise source. The second channel is coupled to a shield layer disposed between the noise source and the electrode layer. The method, apparatus, and system generate an estimated noise signal using the second noise component of the second signal that is associated with the second channel. The method, apparatus, and system subtract the estimated noise signal from the measured first signal to obtain the touch data component of the first signal.

Abstract: A capacitive fingerprint sensor includes a set of capacitive sensor electrodes in a sensing area. The set of capacitive sensor electrodes includes a set of transmit (Tx) sensor electrodes, a set of receive (Rx) sensor electrodes, and a set of compensation electrodes. The fingerprint sensor also includes a multiphase capacitance sensor that is configured to perform a sensing scan of the capacitive sensor electrodes by applying a first Tx signal to a first subset of the Tx sensor electrodes while simultaneously applying a second Tx signal to a second subset of the set of Tx sensor electrodes, and based on a compensation signal received at the set of compensation electrodes, reduce a component of the Rx signal originating from a source other than a contact at the sensing area.

Abstract: A fingerprint sensor-compatible overlay material which uses anisotropic conductive material to enable accurate imaging of a fingerprint through an overlay is disclosed. The anisotropic conductive material has increased conductivity in a direction orthogonal to the fingerprint sensor, increasing the capacitive coupling of the fingerprint to the sensor surface, allowing the fingerprint sensor to accurately image the fingerprint through the overlay. Methods for forming a fingerprint sensor-compatible overlay are also disclosed.

Abstract: Various embodiments provide an object recognition process that is configured to detect a passive stylus and reject non-passive stylus objects on a touch screen, including an edge portion of the touch screen. In one embodiment, the object recognition process includes receiving sense signals from sense elements of a sense array in response to a touch object being on the sense array, selecting three sense signals from three respective sense elements, calculating a first sum of the strengths of the three selected signals, calculating a second sum of the strengths of two of the selected signals which are greater than the strength of one of the selected signals; and determining a type of the object (e.g., a passive stylus or a user hand's grip shadow) based on the first sum and the second sum.

Abstract: A capacitive fingerprint sensor includes a set of capacitive sensor electrodes in a sensing area. The set of capacitive sensor electrodes includes a set of transmit (Tx) sensor electrodes, a set of receive (Rx) sensor electrodes, and a set of compensation electrodes. The fingerprint sensor also includes a multiphase capacitance sensor that is configured to perform a sensing scan of the capacitive sensor electrodes by applying a first Tx signal to a first subset of the Tx sensor electrodes while simultaneously applying a second Tx signal to a second subset of the set of Tx sensor electrodes, and based on a compensation signal received at the set of compensation electrodes, reduce a component of the Rx signal originating from a source other than a contact at the sensing area.

Abstract: An apparatus including a first signal generator of a force sensing circuit to output a first excitation (TX) signal on a first terminal and a second TX signal on a second terminal. The first terminal and the second terminal are configured to couple to a first force sensor and a reference sensor. The apparatus includes a first receiver channel coupled to a third terminal and a fourth terminal. The third terminal is configured to couple to the first force sensor and the fourth terminal is configured to couple to the reference sensor. The force sensing circuit is configured to measure a first receive (RX) signal from the first force sensor via the third terminal and a second RX signal from the reference sensor via the fourth terminal. The force sensing circuit is configured to measure a force value indicative of a force applied to the first force sensor.

Abstract: An example system drives one or more transmit signals on first electrodes disposed in a first layer and propagating electrodes disposed in a second layer. The system measures a capacitance of sensors through a of second electrodes. Each second electrode crosses each first electrode to provide a plurality of discrete sensor areas, each discrete sensor area associated with a difference crossing and including a portion of at least one propagating electrode. Each second electrode is galvanically isolated from the first electrodes and the propagating electrodes.

Abstract: A fingerprint sensor-compatible overlay material which uses anisotropic conductive material to enable accurate imaging of a fingerprint through an overlay is disclosed. The anisotropic conductive material has increased conductivity in a direction orthogonal to the fingerprint sensor, increasing the capacitive coupling of the fingerprint to the sensor surface, allowing the fingerprint sensor to accurately image the fingerprint through the overlay. Methods for forming a fingerprint sensor-compatible overlay are also disclosed.

Abstract: An example sensor array includes a first electrode disposed in a first layer, multiple second electrodes disposed in a second layer, and multiple third electrodes disposed outside of the first layer. The second electrodes are galvanically isolated from the first electrode and the third electrodes. In a plan view of the fingerprint sensor array, an area of each third electrode is located within an area of the first electrode.

Abstract: A fingerprint sensor-compatible overlay material which uses anisotropic conductive material to enable accurate imaging of a fingerprint through an overlay is disclosed. The anisotropic conductive material has increased conductivity in a direction orthogonal to the fingerprint sensor, increasing the capacitive coupling of the fingerprint to the sensor surface, allowing the fingerprint sensor to accurately image the fingerprint through the overlay. Methods for forming a fingerprint sensor-compatible overlay are also disclosed.

Abstract: A fingerprint sensor-compatible overlay material which uses anisotropic conductive material to enable accurate imaging of a fingerprint through an overlay is disclosed. The anisotropic conductive material has increased conductivity in a direction orthogonal to the fingerprint sensor, increasing the capacitive coupling of the fingerprint to the sensor surface, allowing the fingerprint sensor to accurately image the fingerprint through the overlay. Methods for forming a fingerprint sensor-compatible overlay are also disclosed.

Abstract: An example sensor array includes a first electrode disposed in a first layer, multiple second electrodes disposed in a second layer, and multiple third electrodes disposed outside of the first layer. The second electrodes are galvanically isolated from the first electrode and the third electrodes. In a plan view of the fingerprint sensor array, an area of each third electrode is located within an area of the first electrode.

Abstract: Fingerprint detection circuits with common mode noise rejection are described. The Fingerprint detection circuit includes a half-bridge circuit coupled to a receive (RX) electrode of an array of fingerprint detection electrodes and to a buried capacitance that is unalterable by the presence of a conductive object on the array. The fingerprint detection circuit may also include a listener electrode configured to enable common mode noise rejection through a differential input stage of a low noise amplifier (LNA).

Abstract: A capacitive fingerprint sensor includes a set of capacitive sensor electrodes in a sensing area. The set of capacitive sensor electrodes includes a set of transmit (Tx) sensor electrodes, a set of receive (Rx) sensor electrodes, and a set of compensation electrodes. The fingerprint sensor also includes a multiphase capacitance sensor that is configured to perform a sensing scan of the capacitive sensor electrodes by applying a first Tx signal to a first subset of the Tx sensor electrodes while simultaneously applying a second Tx signal to a second subset of the set of Tx sensor electrodes, and based on a compensation signal received at the set of compensation electrodes, reduce a component of the Rx signal originating from a source other than a contact at the sensing area.

Abstract: Various embodiments provide an object recognition process that is configured to detect a passive stylus and reject non-passive stylus objects on a touch screen, including an edge portion of the touch screen. In one embodiment, the object recognition process includes receiving sense signals from sense elements of a sense array in response to a touch object being on the sense array, selecting three sense signals from three respective sense elements, calculating a first sum of the strengths of the three selected signals, calculating a second sum of the strengths of two of the selected signals which are greater than the strength of one of the selected signals; and determining a type of the object (e.g., a passive stylus or a user hand's grip shadow) based on the first sum and the second sum.