| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a solid light-emitting element lighting device which can change the optical output smoothly when a PWM signal for dimming is swept, and to provide a lighting fixture using the same. <P>SOLUTION: The LED lighting device comprises a series circuit of an inductor L1 and a switching element Q1 connected between the output ends of a DC power supply 1 via an LED module 4, a diode D1 which regenerates the energy stored in the inductor L1 in the LED module 4, and a control circuit 3 which performs on/off control of the switching element Q1. The control circuit 3 includes a drive pulse generation unit 34 which generates a drive pulse having a variable pulse width dependent on the amplitude of a load current, and performs on/off control of the switching element Q1 with the drive pulse in the on period of a PWM signal having a frequency lower than that of the drive pulse and an on duty which changes according to the dimming level. Output voltage of the DC power supply 1 is set between 1-2.5 times of a load voltage to the LED module 4. <P>COPYRIGHT: (C)2013,JPO&INPIT |
