| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a short circuit protection device for a semiconductor device that can automatically set optimum parameters even with characteristic differences of a semiconductor element, especially an IGBT, and a temperature change. <P>SOLUTION: In the short circuit protection device for a semiconductor device having charge detection means 22 for detecting a voltage V<SB POS="POST">QG</SB>corresponding to a gate charge Q<SB POS="POST">G</SB>of an IGBT, reference voltage generation means 25 for generating a reference voltage V<SB POS="POST">REF</SB>determinative of whether there is a load short circuit in terms of a charge at an input portion of the IGBT during a rated operation, determination means 27 for determining whether the voltage V<SB POS="POST">QG</SB>detected by the charge detection means 22 is a voltage corresponding to a charge of the IGBT during a rated operation or a voltage corresponding to a charge under a load short circuit, and gate drive means 21 for outputting a signal to stop the operation of the IGBT if the determination means 27 detects a short circuit state, the reference voltage generation means 25 is provided with storage means 26 for detecting and storing a voltage V<SB POS="POST">PEAK</SB>stabilized at a high level of the gate charge voltage V<SB POS="POST">QG</SB>corresponding to the charge at the input portion of the IGBT during a rated operation. <P>COPYRIGHT: (C)2013,JPO&INPIT |
