METHOD AND APPARATUS FOR DRIVING A LIGHT EMITTING DIODE

摘要

An LED drive circuit includes a current source configured to electrically drive an LED. In one configuration, the current source forms part of an integrated circuit that requires a relatively small amount of voltage for operation. As such, separate voltage sources can be electrically coupled to the LED and integrated circuit respectively. For example, a first voltage source provides a source voltage to the LED that is sufficient to allow operation of the LED and a second voltage source provides a source voltage to the integrated circuit that is sufficient to allow operation of the integrated circuit but that is less than a voltage operable to activate the LED. As a result, a low voltage source can be used as a supply for all of the circuitry associated with the integrated circuit, including the current source, without sacrificing the supply voltage used to drive the LED.