POSITION DETECTING CIRCUIT FOR TOUCH PANEL

摘要

PROBLEM TO BE SOLVED: To dispense with any electronic switch control port, to simplify timing control, and to simultaneously recognize X and Y coordinates. SOLUTION: This position detecting circuit of a touch panel 1 to be touched with a touch point is provided with a bias impressing/current detecting circuit 2 using an operating amplifier for recognizing the X and Y coordinates of the touch point by detecting respective currents I3, I4, I1 and I2 running through respective electrodes X1, X2, Y1 and Y2 in the X and Y directions of the touch panel.