Abstract: A device includes an electrical circuit and a mutual-capacitance sensing circuit coupled to the electrical circuit. The mutual-capacitance sensing circuit includes mutual-capacitance sensing electrodes including a transmitter electrode and receiver electrode. The device also includes a conductive overlay over the mutual-capacitance sensing electrodes. The mutual-capacitance sensing circuit is configured to detect deflection of a portion of the conductive overlay relative to the mutual-capacitance sensing electrodes. The receiver electrode has a shape with an inner edge, and the transmitter electrode has a shape with an outer edge that is at least partially surrounded by the inner edge of the receiver electrode.

Abstract: An apparatus includes a moveable electrode which moves along an interstitial pathway defined by four fixed electrodes. The first and second fixed electrodes are separated by a first distance. The third and fourth fixed electrodes are separated by a second distance and adjacent to the first and second fixed electrodes, respectively. A capacitance sensing circuit coupled to the four fixed electrodes determines a first capacitance using the first and second fixed electrodes and a second capacitance using the third and fourth fixed electrodes. In some examples, the apparatus also comprises fifth and sixth fixed electrodes separated by a third distance and orthogonal to the first and second fixed electrodes and seventh and eighth fixed electrodes separated by a fourth distance and orthogonal to the third and fourth fixed electrodes. The fifth and seventh fixed electrodes are adjacent, and the sixth and eighth fixed electrodes are adjacent.

Abstract: A system includes a housing, a sensing electrode disposed within the housing, and a connecting electrode. The system also includes a capacitive sensing circuit galvanically connected to the connecting electrode at a first port, but not to the sensing electrode. The capacitive sensing circuit is configured to determine a first capacitance between the first port and a ground. The first capacitance includes a variable capacitance between the connecting electrode and a person when the person is touching the housing.

Abstract: An apparatus includes a first electrode, a second electrode, and a third electrode having first and second opposing surfaces. The first opposing surface is adjacent the first electrode and separated from the first electrode by a first distance, and the second opposing surface is adjacent the second electrode and separated from the second electrode by a second distance. The third electrode is configured to move relative to the first and second electrodes. A capacitance sensing circuit is coupled to the first and second electrodes. The capacitive sensing circuit is configured to determine a capacitance using the first and second electrodes.

Abstract: Described example user interface control apparatus includes a first structure, with a first side, conductive capacitor plate structures spaced along a first direction on the first side, a movable second structure with an auxiliary conductive structure, and an interface circuit to provide excitation signals to, and receive sense signals from, the conductive capacitor plate structures to perform a mutual capacitance test and a self-capacitance test of individual ones of the conductive capacitor plate structures to determine a position of the second structure or a user's finger relative to the first structure along the first direction.

Abstract: A device includes an electrical circuit and a mutual-capacitance sensing circuit coupled to the electrical circuit. The mutual-capacitance sensing circuit includes mutual-capacitance sensing electrodes including a transmitter electrode and receiver electrode. The device also includes a conductive overlay over the mutual-capacitance sensing electrodes. The mutual-capacitance sensing circuit is configured to detect deflection of a portion of the conductive overlay relative to the mutual-capacitance sensing electrodes. The receiver electrode has a shape with an inner edge, and the transmitter electrode has a shape with an outer edge that is at least partially surrounded by the inner edge of the receiver electrode.

Abstract: An apparatus includes a first oscillator circuit coupled to a first electrode and a second oscillator circuit coupled to a second electrode. The first and second oscillator circuits oscillate synchronously in response to a capacitance between the first and second electrodes being greater than or equal to a threshold coupling capacitance and asynchronously in response to the capacitance being less than the threshold coupling capacitance. The first and second electrodes are separated by a distance, such that a disturbance within the distance increases the capacitance between the electrodes equal to or above the threshold coupling capacitance. The frequency of the first oscillator circuit is inversely proportional to a capacitance of the first electrode, and the frequency of the second oscillator circuit is inversely proportional to a capacitance of the second electrode.

Abstract: A device includes an electrical circuit and a mutual-capacitance sensing circuit coupled to the electrical circuit. The mutual-capacitance sensing circuit includes mutual-capacitance sensing electrodes including a transmitter electrode and receiver electrode. The device also includes a conductive overlay over the mutual-capacitance sensing electrodes. The mutual-capacitance sensing circuit is configured to detect deflection of a portion of the conductive overlay relative to the mutual-capacitance sensing electrodes. The receiver electrode has a shape with an inner edge, and the transmitter electrode has a shape with an outer edge that is at least partially surrounded by the inner edge of the receiver electrode.

Abstract: Described example user interface control apparatus includes a first structure, with a first side, conductive capacitor plate structures spaced along a first direction on the first side, a movable second structure with an auxiliary conductive structure, and an interface circuit to provide excitation signals to, and receive sense signals from, the conductive capacitor plate structures to perform a mutual capacitance test and a self-capacitance test of individual ones of the conductive capacitor plate structures to determine a position of the second structure or a user's finger relative to the first structure along the first direction.

Abstract: Described example user interface control apparatus includes a first structure, with a first side, conductive capacitor plate structures spaced along a first direction on the first side, a movable second structure with an auxiliary conductive structure, and an interface circuit to provide excitation signals to, and receive sense signals from, the conductive capacitor plate structures to perform a mutual capacitance test and a self-capacitance test of individual ones of the conductive capacitor plate structures to determine a position of the second structure or a user's finger relative to the first structure along the first direction.

Abstract: A device includes an electrical circuit and a mutual-capacitance sensing circuit coupled to the electrical circuit. The mutual-capacitance sensing circuit includes mutual-capacitance sensing electrodes including a transmitter electrode and receiver electrode. The device also includes a conductive overlay over the mutual-capacitance sensing electrodes. The mutual-capacitance sensing circuit is configured to detect deflection of a portion of the conductive overlay relative to the mutual-capacitance sensing electrodes. The receiver electrode has a shape with an inner edge, and the transmitter electrode has a shape with an outer edge that is at least partially surrounded by the inner edge of the receiver electrode.

Abstract: An apparatus includes a first oscillator circuit coupled to a first electrode and a second oscillator circuit coupled to a second electrode. The first and second oscillator circuits oscillate synchronously in response to a capacitance between the first and second electrodes being greater than or equal to a threshold coupling capacitance and asynchronously in response to the capacitance being less than the threshold coupling capacitance. The first and second electrodes are separated by a distance, such that a disturbance within the distance increases the capacitance between the electrodes equal to or above the threshold coupling capacitance. The frequency of the first oscillator circuit is inversely proportional to a capacitance of the first electrode, and the frequency of the second oscillator circuit is inversely proportional to a capacitance of the second electrode.

Abstract: Disclosed examples include optical and capacitive position detection systems and user interface control apparatus to detect relative positions of a stationary first structure and a movable second structure. The optical system includes pairs of optical source and sensor devices spaced along a first direction on the first structure and a reflector extending along the first direction on the second structure to selectively reflect light from one of the optical sources to the corresponding optical sensor of a given pair when the reflector is proximate the given pair. The capacitive sensing system includes capacitor plate structures on the first structure and a conductive structure on the second structure to move along the first direction to selectively modify a capacitance of a given group of two or more of the plate structures.

Abstract: An apparatus includes a first electrode, a second electrode, and a third electrode having first and second opposing surfaces. The first opposing surface is adjacent the first electrode and separated from the first electrode by a first distance, and the second opposing surface is adjacent the second electrode and separated from the second electrode by a second distance. The third electrode is configured to move relative to the first and second electrodes. A capacitance sensing circuit is coupled to the first and second electrodes. The capacitive sensing circuit is configured to determine a capacitance using the first and second electrodes.

Abstract: An apparatus includes a moveable electrode which moves along an interstitial pathway defined by four fixed electrodes. The first and second fixed electrodes are separated by a first distance. The third and fourth fixed electrodes are separated by a second distance and adjacent to the first and second fixed electrodes, respectively. A capacitance sensing circuit coupled to the four fixed electrodes determines a first capacitance using the first and second fixed electrodes and a second capacitance using the third and fourth fixed electrodes. In some examples, the apparatus also comprises fifth and sixth fixed electrodes separated by a third distance and orthogonal to the first and second fixed electrodes and seventh and eighth fixed electrodes separated by a fourth distance and orthogonal to the third and fourth fixed electrodes. The fifth and seventh fixed electrodes are adjacent, and the sixth and eighth fixed electrodes are adjacent.

Abstract: A system includes a housing, a sensing electrode disposed within the housing, and a connecting electrode. The system also includes a capacitive sensing circuit galvanically connected to the connecting electrode at a first port, but not to the sensing electrode. The capacitive sensing circuit is configured to determine a first capacitance between the first port and a ground. The first capacitance includes a variable capacitance between the connecting electrode and a person when the person is touching the housing.

Abstract: Disclosed examples include optical and capacitive position detection systems and user interface control apparatus to detect relative positions of a stationary first structure and a movable second structure. The optical system includes pairs of optical source and sensor devices spaced along a first direction on the first structure and a reflector extending along the first direction on the second structure to selectively reflect light from one of the optical sources to the corresponding optical sensor of a given pair when the reflector is proximate the given pair. The capacitive sensing system includes capacitor plate structures on the first structure and a conductive structure on the second structure to move along the first direction to selectively modify a capacitance of a given group of two or more of the plate structures.

Abstract: Disclosed examples include optical and capacitive position detection systems and user interface control apparatus to detect relative positions of a stationary first structure and a movable second structure. The optical system includes pairs of optical source and sensor devices spaced along a first direction on the first structure and a reflector extending along the first direction on the second structure to selectively reflect light from one of the optical sources to the corresponding optical sensor of a given pair when the reflector is proximate the given pair. The capacitive sensing system includes capacitor plate structures on the first structure and a conductive structure on the second structure to move along the first direction to selectively modify a capacitance of a given group of two or more of the plate structures.

Abstract: Described example user interface control apparatus includes a first structure, with a first side, conductive capacitor plate structures spaced along a first direction on the first side, a movable second structure with an auxiliary conductive structure, and an interface circuit to provide excitation signals to, and receive sense signals from, the conductive capacitor plate structures to perform a mutual capacitance test and a self-capacitance test of individual ones of the conductive capacitor plate structures to determine a position of the second structure or a user's finger relative to the first structure along the first direction.

Abstract: Described example user interface control apparatus includes a first structure, with a first side, conductive capacitor plate structures spaced along a first direction on the first side, a movable second structure with an auxiliary conductive structure, and an interface circuit to provide excitation signals to, and receive sense signals from, the conductive capacitor plate structures to perform a mutual capacitance test and a self-capacitance test of individual ones of the conductive capacitor plate structures to determine a position of the second structure or a user's finger relative to the first structure along the first direction.