| 摘要 |
PURPOSE:To attain duplex system constitution, by corresponding one point to be scanned at two arbitrary cross points of different row and column of a scanning matrix for points to be scanned of an exchange system and providing a reverse-flow preventing diode between the point to be scanned and drive and readout lines. CONSTITUTION:In a scanning matrix circuit S11, an output of a scanning drive circuit DV1 is connected to a node N1 via a drive line X1 and a diode D1. The input of a read circuit SA1 is connected to the node N1 via a reading line Y1 and a diode D2. The node N1 is connected to a point (a) to be scanned via a resistor R and the reverse-flow preventing diode DM. A scanning matrix circuit S22 is constituted similarly and connected to the same point (a). Thus, a duplex scanning matrix circuit is obtained without two scanning matrix circuits. |
