US Patent 10031632 Pseudo driven shield

In one embodiment, a device includes a controller, first electrodes, second electrodes, a plurality of sensors, and a shield sensor. The controller is operable to cause substantially equal voltages to be present on the first and second electrodes while measuring capacitances of the plurality of first electrodes electrically coupled to the shield sensor and measuring capacitances of the plurality of second electrodes electrically coupled to the plurality of sensors.