Patent ID: 7592754

Claim:
An integrated circuit (IC), comprising: a first pin configured to electrically couple to a first voltage source, the first voltage source configured to provide a supply voltage to the IC; a second pin configured to couple to a light emitting diode (LED), the LED configured to electrically couple to a second voltage source configured to provide a supply voltage to the LED, the second voltage source being different than the first voltage source; a current generator coupled to the second pin and configured to (i) conduct a first current through the LED, the first current sufficient to cause the LED to emit light and (ii) conduct a second current through the LED, the second current being insufficient to cause the LED to emit light; and a pull down resistor coupled to the second pin, the current generator configured to (i) conduct the first current having the first current value through the LED, the first current sufficient to cause the LED to emit light and (ii) conduct the second current through the LED, the second current being equal to zero amperes; the pull down resistor configured to conduct a third current through the LED, the third current being insufficient to cause the LED to emit light.