| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply device that protects a circuit by discriminating between wiring short-circuiting and a contact defect of a connector. SOLUTION: In the power supply device, since a semiconductor device T1 is insulated before a voltage V1 at the drain of the semiconductor device T1 drops below the lowest in-phase input voltage of a comparator CMP1, a load circuit is reliably protected. When the voltage V1 satisfies "V1<L_V1" where L_V1 is a first decision voltage and V3 is a second decision voltage, retry operation is performed, and when the voltage V1 satisfies "V1<L_V1" N1 times, or when "L_V1<V1<V3" is satisfied N2 times, the semiconductor device T1 is held in the insulated state to protect the load circuit. Further, when the V1 abruptly drops due to the contact defect of the connector 11, the lowest value of the voltage V1 is not a stable value and the insulated state of the semiconductor device T1 is not held. COPYRIGHT: (C)2010,JPO&INPIT |
