LIGHTING DEVICE INCLUDING A DRIVE DEVICE CONFIGURED FOR DIMMING LIGHT - EMITTING DIODES IN RESPONSE TO VOLTAGE AND TEMPERATURE

摘要

There is provided a lighting device 100 having a drive device 108 for dimming the light emitting diode 104. Drive device 108 includes a dimming component 110 that operates switch 112 in response to a change in both an input power signal and a system temperature. In one example, dimming apparatus 110 may include a waveform generator that generates a signal having a waveform having a varying level in response to a change in temperature. The waveform defines the time the switch is open and closed, thereby determining the duration of time that the LED is energized. By operating the LEDs in this manner, the drive device 108 effectively dims the LEDs to reduce the operating temperature and cool the LEDs.