| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an automatic flashing street lamp capable of breaking and protecting a circuit promptly when an insulation failure and a short circuit occur in a lamp circuit and a voltage converter. SOLUTION: In this automatic flashing street lamp, a charger 917 stores power generated by a solar cell 918 in daytime in a storage battery 101. When it becomes dark, a voltage between terminals of a photodiode PD reaches beyond a divided voltage of R91 and R92 so that output of a comparator 911 becomes high and a driving voltage is applied to a control terminal C of a switch device 110 with a current oscillation breaking function. Then, the switch device 110 is brought into a conductive state at D-S, a voltage VB of the storage battery 101 is applied to a voltage converter and the lamp 915 is turned on. The switch device 110 breaks load current when a short-circuit in a load or layer short occurs.</p> |
