| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a driving circuit of an LED lamp which can be used by replacing an existing straight tube type fluorescent lamp and can modulate light in a PWM method. <P>SOLUTION: A straight tube type led lamp 10 is attached to lighting equipment having a commercial power supply 40 as an input for driving during light modulation. To one lateral pair of contact pins 13, power supply voltage is applied from a socket 30A of lighting equipment, the power supply voltage is rectified to be input to a constant current switching circuit, a PWM signal is input to another lateral pair of contact pins from a socket 30B of lighting equipment. In response to the PWM signal, a pulse-like constant current is output from the constant current switching circuit, and according to the pulse-like constant current, an LED circuit is electrified so that the LED emits light. Light modulation is performed with a pulse width of the constant current, and a photo coupler 100 electrically insulates between another lateral contact pin 13 and the switching circuit. <P>COPYRIGHT: (C)2013,JPO&INPIT |
