| 摘要 |
PURPOSE:To extend the service life of a contactless switching circuit and to improve its reliability by attaining the contactless switching circuit using an n-channel MOS transistor(TR) by a simple circuit constitution. CONSTITUTION:The contactless switch circuit is provided with an n-channel MOS field effect transistor(FET) inserted into a negative pole side feeder to a load 50 in series so that its source electrode S and drain electrode D are respectively connected to the power supply side and the load side, a bias circuit 52 for applying a bias voltage to the gate electrode G of the MOS FET 51 to turn on the MOS FET 51 and a bias stopping circuit 53 for turning the MOS FET 51 to an OFF state by stopping the impression of the bias voltage by the circuit 52. |
