| 摘要 |
PROBLEM TO BE SOLVED: To provide a dropper type stabilized power circuit which can prevent a reverse current from flowing from the output side to the input side even if the output-side voltage becomes higher than the input voltage in a state where a high-temperature leak compensating resistance is provided. SOLUTION: In normal operation, the output voltage Vo detected by an output voltage detecting circuit 15 is less than a specific value set below a value which exceeds the output voltage in the normal operation and at which a current begins to flow from the collector to the base of a power transistor 11 and a switch drive circuit 16 outputs a control signal for turning on a switch SW1 for the compensating resistance. Consequently, the high-temperature leak compensating resistance REB becomes able to function. When the voltage at the output terminal OUT rises above the specific value, the switch drive circuit 16 outputs a control signal for turning off the switch SW1 so that no current flows to the high-temperature leak compensating resistance REB.
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