Touch panel controller and semiconductor device

摘要

The drive circuit operable to output a drive pulse pattern to drive electrodes of a touch panel is arranged so that it can change the pulse frequency of the drive pulse pattern for each drive electrode. The detection circuit operable to detect signal changes arising on detection electrodes of the touch panel for each drive pulse pattern output by the drive circuit is arranged so that it can change the sampling frequency of signal change for each detection electrode. The range to make higher the pulse frequency of the drive pulse pattern for each drive electrode, and the sampling frequency of signal change for each detection electrode is variably controlled according to a touch position where a touch has been detected by use of a detection signal detected by the detection circuit.

主权项

1. A touch panel controller comprising:
a drive circuit operable to output drive pulse patterns to drive electrodes of a touch panel sequentially; a detection circuit operable to detect signal changes arising on detection electrodes of the touch panel for each drive pulse pattern output by the drive circuit; and a control circuit operable to control the drive circuit and the detection circuit, wherein the drive circuit is capable of changing a pulse frequency of the drive pulse pattern for each drive electrode, the detection circuit is capable of changing a sampling frequency of signal change for each detection electrode, and the control circuit controls, within a predetermined range, a pulse frequency of the drive pulse pattern for each drive electrode, and a sampling frequency of signal change for each detection electrode so as to raise the pulse and sampling frequencies, provided that the predetermined range can be changed depending on a touch position where a touch has been detected by use of a detection signal detected by the detection circuit.