| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately specify a pressurized coordinate position on respective coordinate axes by calculating voltage drop by the ON resistance of an analog switch and removing it. SOLUTION: The analog switches 12-15 are controlled by the I/O ports 31-34 of an arithmetic storage part 30 and respective electrodes 4-7 are connected to voltage follower circuits 20-23. The arithmetic storage part 30 outputs changeover signals connected to a multiplexer 41 from the I/O ports 35 and 36, one from the output of the voltage follower circuits 20-23 is selected, the potential of a pertinent electrode is digitally converted by an A/D converter 42 and potential information is obtained. The potential information outputted from a potential detection circuit 40 is written in a RAM 52 through a data bus 54 and a CPU 51 performs the processing of a control method based on a program stored in a ROM 53, specifies the respective coordinate positions of an X coordinate axis and a Y coordinate axis and calculates the pressurized coordinate position of a touch panel 1.</p> |
