| 摘要 |
PROBLEM TO BE SOLVED: To provide a failure detection circuit having a circuit for detecting short-circuit failure of capacitors on a low voltage circuit side.SOLUTION: A high voltage signal Vcan from a high voltage circuit 1 is fed to a reception circuit 5 through capacitors 3 and 4 connected in series. Voltage at a common connection point of the capacitors 3, 4 is reduced by a voltage reduction circuit 11 and fed to a detection circuit 12. A voltage signal Vcmp is low when the capacitors 3, 4 are in a normal state as a DC component is cut off thereby. In the event of a short circuit failure of the capacitor 3 or 4, the voltage signal Vcmp becomes high as the DC component is added to the signal. A short-circuit failure state of the capacitor 3 or 4 is thus detected from an operational state of the reception circuit 5.SELECTED DRAWING: Figure 2 |
