| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a light emitting diode driving device at a high efficiency which can considerably reduce a power loss due to a current limit resistance. <P>SOLUTION: In the light emitting diode driving device 1, a first energization state S1 and a second energization state S2 are alternately switched to drive to emit a light from a light emitting diode 2. In the first energization state S1, an inductor L1 is connected to the light emitting diode 2 on a main drive line 3, to accumulate a magnetic energy in the inductor L1 while supplying a main drive current. In the second energization state S2, a supply of the main drive current to the main drive line 3 is cut off, while the magnetic energy accumulated in the inductor L1 is released as an auxiliary drive current of the light emitting diode 2 through an auxiliary close current path 7. A power is consumed wastefully by the current limit resistance in a conventional circuit, but the magnetic energy has once be stored in the inductor L1 in the first energization state S1 for a current limit. As the energy stored in the inductor L1 is used for driving the light emitting diode 2 in the second energization state S2, the efficiency is very good. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
