Freescale Semiconductor,inc.

Nxp USA, Inc.

Craig R Teegarden

Bryce T Osoinach

Eiji Shikata

Lawrence T Roshak

Tsukasa Hoshi

Toshiaki Ito

Simon Mejia

Keiji Tenaka

Dennis Hicks

Katsuaki Morishita

Christopher Liebelt

Karen L Collins

Michael T Young

A touch pad controller includes a voltage generator and a selector circuit. The voltage generator has a plurality of output terminals, each of the plurality of output terminals for being coupled to a corresponding pad of a plurality of capacitive touch pads. The voltage generator provides a predetermined voltage to each of a plurality of touch pads in a predetermined sequence. The selector circuit has a plurality of input terminals. Each input terminal of the plurality of input terminals is coupled to an output terminal of the plurality of output terminals of the voltage generator. The selector circuit sequentially couples each output terminal of the plurality of output terminals of the voltage generator to a touch pad shield for charging the touch pad shield to the predetermined voltage.

Touch sensor controller for driving a touch sensor shield

Embodiments include methods and apparatus for performing capacitive touch sensing and proximity detection. Electrode selection circuitry establishes a first connection with an individual electrode of a plurality of individual electrodes in order to receive one or more first signals indicating a state of the individual electrode, and establishes second connections with a proximity electrode that comprises multiple ones of the plurality of individual electrodes in order to receive one or more second signals indicating a state of the proximity electrode. A processing system performs a first analysis on the first signals to determine whether to perform a first updating process for an individual electrode baseline value, and performs a second analysis on the second signals to determine whether to perform a second updating process for a proximity electrode baseline value. In an embodiment, the first analysis and the second analysis are different from each other.

Methods and apparatus for performing capacitive touch sensing and proximity detection

Embodiments include capacitive touch sensors and methods for configuring capacitive touch sensors. A capacitive touch sensor embodiment includes an analog-to-digital converter (ADC) and a controller. The ADC receives an analog voltage signal from an electrode, and samples the analog voltage signal to produce a plurality of digital values. The controller performs a first charging process by supplying the electrode with a first charging current for a first charging interval, and the controller determines, based on the digital values, whether a first electrode voltage value meets a criteria. If not, the controller performs a configuration process that results in setting a second charging current and a second charging interval for the electrode which, in response to performing a second charging process, results in a second electrode voltage value that meets the criteria.

Capacitive touch sensor device configuration systems and methods

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Pittsburgh, PA, United States of America

Craig R Teegarden