| 摘要 |
<p>A position detecting apparatus and a method thereof are provided to optimize an exciting signal, outputted from a surrounding coil, correspondingly to the indication position of a position indicator, dynamically. An exciting coil(19) is arranged around a position detection region and is connected to an oscillation circuit(21) through a drive circuit(20). The oscillation circuit oscillates in a frequency f0. A CPU(18) supplies a control signal, corresponding to a preset program, to a selecting circuit(12), a sample hold circuit(16), an AD converting circuit(17) and the drive circuit. The drive circuit performs the ON/OFF control for a signal power transmitted from the exciting coil based on a control signal supplied from the CPU. A sensor coil has a loop coil group(X1-X40) and a loop coil group(Y1-Y30) and is connected to an amplifier circuit(13) and the AD converting circuit through the selecting circuit.</p> |
