| 摘要 |
<P>PROBLEM TO BE SOLVED: To determine whether a clamp circuit is in an unused state or a disconnected state. <P>SOLUTION: Temperature detection terminals 14a to 14c into which outputs of temperature sensors 1h are input are utilized, and if part of clamp circuits 5a to 5c and temperature detection circuits 7a to 7c are not connected to a power module 1, a disconnection-invalidated state in which the temperature sensor 1h is not connected is detected according to potentials at the temperature detection terminals 14a to 14c. For example, the application of a voltage equal to or higher than a disconnection detection invalidation threshold Vth3 to one of the temperature detection terminals 14a to 14c which is not connected to the temperature sensor 1h detects that the temperature detection terminal 14a to 14c is not connected to the temperature sensor 1h. In disconnection detection based on potentials at clamp terminals 11a to 11c connected to the clamp circuits 5a to 5c, a disconnected state or a disconnection-invalidated state can be determined according to the potentials at the temperature detection terminals 14a to 14c. <P>COPYRIGHT: (C)2013,JPO&INPIT |
