| 摘要 |
<p>PURPOSE:To obtain a coordinate indicator which can send various switch information and also transmit continuous information by composing a parallel resonance circuit of a coil for excitation, a capacitor, and a voltage varactor diode, and using the output voltage of a DC bias circuit as the bias voltage of the voltage varactor diode. CONSTITUTION:An oscillation circuit 1 consists of a drive circuit 1a, a parallel resonance circuit lb, and a feedback circuit 1c. The DC bias voltage circuit 2 consists of resistances R5-R10 which connect a voltage power source Vcc and the ground G in series and SW1-SW4 which each have one end connected to the ground G and the other end connected between specific resistances. The oscillation circuit 1 and DC bias voltage circuit 2 are connected through the resistance R4 at a point A as the connection part of the resistances R5 and R6 and a point B on the bias side of the voltage varactor diode VD. Consequently, various switch information can be transmitted and the continuous information like pressure information can also be detected.</p> |
