| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a temperature detector capable of detecting an open failure etc., generated in a temperature detector. <P>SOLUTION: Diodes 3a-3c are connected with series switches 11a-11c respectively so as to detect the temperatures of IGBT 2a-2c. The diodes 3a-3c are failure diagnosed individually by turning on the switches 11a-11c one by one. A comparator 8 compares a terminal voltage VF of the diode and a reference voltage Vref of reference voltage source 7, and sends the result of comparison to a CPU 10. The CPU 10 determines the diode being NG (open failer) if the terminal voltage VF corresponding to ON switch is higher than the Vref (max). and determines the diode NG (short circuit failure), if the terminal voltage VF is lower than the Vref (min). <P>COPYRIGHT: (C)2004,JPO |
