| 摘要 |
PROBLEM TO BE SOLVED: To provide a capacitance type switch device capable of reducing a difference of detection sensitivity among respective measurement zones and having a wide detection range. SOLUTION: Capacitance Cx between a detection electrode 2 and the ground is divided into (n) regions, and an offset value is assigned to each region. A capacitance detection circuit 8 outputs a detection value obtained by correcting a value according to the capacitance Cx between the detection electrode 2 and the ground by the offset value. A CPU 15 compares and determines the magnitude relation between the detection value from the detection circuit 8 and a preset threshold value, updates the offset value to that of the next region when the detection value exceeds the threshold value, and determines an output value by using the magnitude relation between the detection value and the threshold value and the offset value. COPYRIGHT: (C)2007,JPO&INPIT
|
