Resistive touch screen identifying touch coordinates by using electric charging time of capacitor

摘要

PURPOSE: A resistive touch screen identifying touch coordinates by electric charging time of capacitor is provided to grasp the touch coordinate without using ADC(Analog to Digital Convertor). CONSTITUTION: When it is said that a resistance value formed in a first resistance film is Rv, a resistance value formed in a second resistance film is R_Y+, Y+ same resistance line operating device(302) obtains identical resistance line depending on (R_v + R_Y+) value. When it says to be the resistance value formed in the second resistor film is R_Y-, Y- identical resistance line arithmetic and logic unit(301) obtains the identical resistance line according to (R_v + R_Y-) value. The touch coordinates computing device(400) finds the cross point of the identical resistance line according to the identical resistance line according to (R_v + R_Y+) value and (R_v + R_Y-) value. The touch coordinates computing device recognizes the cross point as the touch coordinates.