| 摘要 |
<p>PURPOSE:To improve reliability of a touch input panel device by trying again the measurement of the panel impedance when a cycle counter of a CR sag/ tension oscillator has an overflow. CONSTITUTION:A CR sag/tension oscillator 11 detects the impedance change of a touch operation panel 10 and outputs pulses of the prescribed width. These pulses are counted by a cycle counter 12 and this count value is sent to a coordinate arithmetic circuit 15 for calculation of the X and Y coordinates of a touch position. If the counter 12 has an overflow owing to the excessive touch capacity produced when an operator touches an input panel while having a contact with the earth level of the touch input panel device, a control circuit part 16 receives the reset signal from the counter 12 and actuates the counter 12 repetitively for the second try of measurement of the panel impedance.</p> |
