Patent ID: 8278571

Claim:
An electronic device, comprising: a mutual capacitance combined finger and active stylus sensing touchscreen or touchpad comprising an outer touch surface, at least one substrate disposed beneath the touch surface, a first plurality of mutual capacitance drive electrodes arranged in first rows or columns on the at least one substrate, a second plurality of mutual capacitance sense electrodes arranged in second rows or columns on the at least one substrate, the first rows or columns not being parallel to the second rows or columns; electrode driving and sensing circuitry operably connected to the drive and sense electrodes and configured to permit at least some of the drive electrodes to be switchably configured thereby for operation as either drive electrodes in a first finger touch mode or as additional sense electrodes in a second active stylus mode, and an active stylus comprising stylus driving circuitry configured to emit an active signal from the active stylus when the touchscreen or touchpad is operating in the second mode, the active signal having the same amplitude, phase and frequency of a drive signal output by the drive electrodes when the drive electrodes are operating in the first finger touch mode; wherein the outer touch surface is configured for a user to place and move the finger or active stylus thereon and thereacross, the first and second pluralities of electrodes form an electrode array, and the electrode driving and sensing circuitry and the electrode array are together configured to permit a first finger position on the outer touch surface to be detected capacitively thereby when operating in the first mode and to detect a second active signal location on the outer touch surface to be detected capacitively thereby when operating in the second mode.