Low pin count solution using capacitance sensing matrix for keyboard architecture

摘要

An apparatus and method for selecting a keyboard key based on a position of a presence of a conductive object on a sensing device and a pre-defined area of the keyboard key. The apparatus may include a sensing device and a processing device. The sensing device may include a plurality of sensor elements to detect a presence of a conductive object on the sensing device. Multiple keyboard keys are assigned to pre-defined areas of the sensing device. The processing device is coupled to the sensing device using capacitance sensing pins, and may be operable to determine a position of the presence of the conductive object, and to select a keyboard key based on the position of the conductive object and the pre-defined areas of the sensing device.

主权项

1. A mobile device comprising:
a processing device comprising a capacitance measurement circuit to couple to an array of a plurality of electrodes, wherein the processing device is configured to determine a position of a conductive object proximate to a sensing surface of the mobile device, wherein the processing device is configured to:
assign a plurality of keys to correspond to defined areas of the sensing surface, wherein the defined areas are disposed adjacent to one another in a key matrix, wherein at least one of the plurality of electrodes is positioned to correspond to at least three of the defined areas;select a key of the key matrix when the position of the conductive object proximate to the sensing surface is determined to be within the defined area corresponding to the key; anddetect a gesture performed by the conductive object on the sensing surface.