| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power supply protection control circuit wherein protection is made without cutting off power supply to a control circuit if abnormal conditions occur in a circuit that uses a switching power supply circuit, and return is enabled by self-diagnosis after the abnormal conditions. <P>SOLUTION: The power supply protection control circuit always monitors a switching power supply circuit for the state of a power supply voltage by means of a power supply voltage monitoring circuit. A comparison detection circuit compares a voltage of the switching power supply circuit which is detected with the power supply voltage monitoring circuit with a predetermined reference voltage. If an output of the comparison detection circuit is equal to the reference voltage or lower, a cut-off circuit cuts off a standby power reducing cut-off circuit. The power supply protection control circuit can assure power supply to a control circuit side even if a power supply for an electronic device is cut off. Therefore, determination of abnormal voltage as well as display of return state and the abnormal conditions can be performed. <P>COPYRIGHT: (C)2009,JPO&INPIT |
