| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a power supply device and an LED lamp device with high efficiency and a low loss. <P>SOLUTION: The power supply device is provided with a power supply device with an alternate-current or direct-current power source inputted from an input terminal, and an LED lamp 106 composed of one or a plurality of LEDs connected in series with an output terminal of the power supply device. The power supply device is provided with a current detection circuit 307 detecting an electric current at the output terminal, an oscillation circuit 310 oscillating pulse signals of desired frequencies, a switching control circuit 322 connected with the oscillation circuit 310, and a switching device 316 connected with the switching control circuit 322. The switching control circuit 322 carries out the on-off control of the switching device 316 at a predetermined frequency by the oscillation circuit outputting a repetitive signal of oscillation, and turns on the LED lamp 106 by supplying a pulse current of a controlled constant current to the LED lamp 106 based on the detected signals from the current detection circuit 307. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
