LED drive circuit
AssigneesCitizen Watch Co., Ltd., Citizen Electronics Co., Ltd.
InventorsKeisuke Sakai, Takashi Akiyama
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AssigneesCitizen Watch Co., Ltd., Citizen Electronics Co., Ltd.
InventorsKeisuke Sakai, Takashi Akiyama
Estimating the term…
An LED drive circuit in which a bright change of an LED is suppressed even if the voltage of a full-wave rectified waveform fluctuates is provided. The LED drive circuit includes a bridge rectifier circuit, an LED string made up by a plurality of LEDs being connected in series and supplied with a current from the bridge rectifier circuit, and a current limiting circuit that has a current input terminal and a current output terminal connected onto a path that starts from the bridge rectifier circuit and returns to the bridge rectifier circuit via the LED string, which limits a current that flows through the LED string to an upper limit current value or smaller, and further, which decreases the upper limit current value in accordance with the amount of rise in the voltage when the voltage at the current input terminal viewed from the current output terminal rises.
An LED drive circuit comprising:
Dependencies are inferred from the claim text.