| 摘要 |
PROBLEM TO BE SOLVED: To prevent malfunction and improve reliability of a circuit by preventing a wrong signal from being output from an insulation means even by overlapping of noise in a signal cable or the like. SOLUTION: This inverter circuit 100 is provided with a transistor TR1, TR2 connected to a 12 V power source and a 5 V power source, to be on/off controlled by a drive signal from a control unit ECU to be formed with a signal current comprising an on/off current flowing in a signal cable 3; and a photo- coupler Ph1, Ph2 connected to the 5 V power source to perform on-driving when a signal current value flowing in the signal cable 3 exceeds a prescribed on-threshold value, while performing off-driving when the signal current value comes to be less than a prescribed off-threshold value. A bipolar transistor circuit 2 lowering down the signal current value to a minus side, when the transistor TR1, TR2 is turned off, is provided between the transistor TR1, TR2 and the photo-coupler Ph1, Ph2. |
