Patent ID: 8581857

Claim:
A capacitive type position detecting device comprising: (a) a plurality of first electrodes arranged in a first direction; (b) a plurality of second electrodes arranged in a second direction that is substantially perpendicular to the first direction; (c) a signal supplying circuit including a clock signal generator configured to generate a clock signal having a clock period of CLK, the signal supplying circuit being configured to supply signals having a waveform, which includes a determined time width (TIME_WIDTH) between a rising part and a falling part of the waveform, to the plurality of first electrodes arranged in the first direction when TIME_WIDTH is an integer (s≧2) multiple of CLK, wherein the signal supplying circuit is further configured to sequentially supply said signals of TIME_WIDTH to the first electrode Yn through Y {n+s} that are adjacent to each other per every CLK such that (s+l) is a total number of the first electrodes to which the rising parts of said signals of TIME_WIDTH are sequentially supplied within TIME_WIDTH, and the signal supplying circuit is further configured such that the rising part of the waveform in said signal supplied to the first electrode Y {n+s} occurs at the same time as the falling part of the waveform in said signal supplied to the first electrode Yn and no rising and falling parts of two adjacent first electrodes coincide with each other; wherein, in a selected one of the second electrodes with which said first electrodes Yn and Y {n+s} intersect to form two intersections, a first current is generated at a timing of the rising part of the waveform supplied to said first electrode Y {n+s} and a second current is generated at a timing of the falling part of the waveform supplied to said first electrode Yn, the first current and the second current being combined to form a combined current signal in the selected one of the second electrodes, (d) a current-to-voltage converter configured to be directly coupled to only the selected one of the second electrodes to convert the combined current signal to an analog voltage signal; (e) an A/D converter configured to convert the analog voltage signal to a digital voltage signal; and (f) a position calculating section configured to detect a position indicated by a position indicator on the position detecting device based on said digital voltage signal originating in the selected one of the second electrodes and received via said current-to-voltage converter and said A/D converter, wherein, in a case where the position indicator is not present near the two intersections, the first current and the second current generated at the timings of the rising and falling parts of the waveform substantially cancel each other in the selected one of the second electrodes, and in a case where the position indicator is present on or near one of the two intersections, the first current and the second current do not substantially cancel each other in the selected one of the second electrodes.