Patent ID: 8766930

Claim:
A capacitive touchscreen system, comprising: a touchscreen comprising a first plurality of electrically conductive traces arranged in rows or columns, and a second plurality of electrically conductive traces arranged in rows or columns arranged at an angle with respect to the rows or columns of the first plurality of electrodes, mutual capacitances existing between the first and second pluralities of traces at locations where the first and second pluralities of traces intersect, such mutual capacitances changing in the presence of one or more fingers or touch devices brought into proximity thereto; first drive-sense circuits, one each of such first drive-sense circuits being operably connectable to a corresponding one of the first plurality of traces by switching circuitry, each first drive-sense circuit being operably connectable to its corresponding trace and to a first amplifier, a first capacitor being operably connected to a first negative input and a first output of the first amplifier, and to a first comparator operably connected to the first output of the first amplifier, second drive-sense circuits, one each of such second drive-sense circuits being operably connectable to a corresponding one of the second plurality of traces by switching circuitry, each second drive-sense circuit being operably connectable to its corresponding trace and a second amplifier, a second capacitor being operably connected to a second negative input and a second output of the second amplifier, and to a second comparator operably connected to the second output of the second amplifier, and a drive/sense processor operably connected to the first and second drive-sense circuits, respectively, and configured: (a) to control the first plurality of first drive-sense circuits to drive at least some of the first plurality of traces; and to control the second plurality of second drive-sense circuits to sense at least one first voltage associated with at least some of the mutual capacitances through the second plurality of traces and to compare the first voltage with a predetermined voltage threshold, and (b) to control the second drive-sense circuits to drive at least some of the second plurality of traces; and to control the first drive-sense circuits to sense at least one second voltage associated with at least some of the mutual capacitances through the first plurality of traces, and to compare the second voltage with the predetermined voltage threshold; wherein the detection of locations of multiple simultaneous or near-simultaneous touches on the touchscreen is accomplished via the step (a) and the step (b) performed by the drive/sense processor.