摘要 |
A constant or variable flashlight includes a semi-conductor boost/buck controller electrically connected to an inductor. The controller is operable to cyclically charge the inductor and then cause the stored energy to be delivered to the flashlight lamp in cycles repeating at a rate between 10,000 and one million cycles per second. A photo-responsive feedback circuit connected to the controller is operable for modulating the current to the lamp in response to an imbalance between a standard potential and the feedback circuit. Arrangements are provided for selectively changing the brightness of the lamp necessary to produce a balance of potential between the standard potential and the feedback current.
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