| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To detect that an LED is normally connected by a ripple detection section connected in parallel to the LED when the LED is connected to an output terminal of a DC power supply. <P>SOLUTION: An LED module 5 is detachably connected to an LED lighting device 110. A ripple detection section 101 that is a CR differentiation circuit composed of a series connection of a capacitor 62 and a resistor 61 electrically forms a parallel connection with the LED module 5 when the LED module 5 is connected. The ripple detection section 101 detects a ripple component of a voltage across a smoothing capacitor 44. An output control circuit 46 controls switching of a transistor 41 of a constant-current power supply 4 according to the ripple component of the capacitor 44 detected by the ripple detection section 101. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
