| 摘要 |
PROBLEM TO BE SOLVED: To provide an abnormality detecting apparatus capable of grasping a cause to abnormality caused onto a path of a video signal. SOLUTION: The abnormality detecting apparatus includes: an abnormality detection circuit 11 for obtaining a DC signal level from an output path through which a video signal outputted from a camera 2 or an external video output unit 3 is outputted to a display apparatus 4; and a CPU 10, and the CPU 10 discriminates that the output path is in a short circuit state when a voltage at a cathode of a Zener diode ZD stays within a prescribed range including a Zener voltage of the Zener diode ZD, discriminates that the output path is in an open state when the voltage at the output path is within a prescribed range including a voltage pulled up by a pull-up circuit (D4, D8), discriminates that the output path is in a normal state when an output voltage of a smoothing circuit (C2, D1) is within a predetermined range, and discriminates that the output path is in an earth fault state when a voltage of the video signal is within a prescribed range including a ground level. COPYRIGHT: (C)2007,JPO&INPIT
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