| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an LED lighting device capable of both preventing flicker and down-sizing of the device. <P>SOLUTION: Positive and negative output terminals of a bridge diode 3 that performs full-wave rectification of an AC voltage output from an AC voltage source 2 are connected to the both terminals of a series circuit of an LED module 6, a constant current circuit 5, and a switching circuit 4. The constant current circuit 5 has a normally-on type GaN-FET 21 whose gate and source are connected together. The switching circuit 4 includes: an oscillator 11 that outputs an oscillation signal whose frequency is higher than that of output voltage of the AC voltage source 2, according to voltage output from the constant current circuit 5; and a switching MOS-FET 15 having a gate to which the oscillation signal is supplied. In the switching circuit 4, conduction/non-conduction control of the LED module 6 is performed by on-off control of the MOS-FET 15 by means of the oscillation signal. <P>COPYRIGHT: (C)2012,JPO&INPIT |
