Laser diodes are employed in digital optical data communications applications as they have relatively high bandwidth resulting in high data rates. In order to control a laser diode, a modulation reference current and a bias current are applied to the laser diode. A laser driving circuit can receive a data signal that drives a laser diode based upon the modulation reference current and the bias current. Typically, the bias current is that which is necessary to maintain a substantially constant “0” power level in the laser diode. The modulation reference current is that which is necessary to maintain a substantially constant “1” power level in the laser diode. In order to transmit data, the laser bias current and the modulation reference current are employed to cause the laser to transmit data using a constant “0” power level and a constant extinction ratio, which is the ratio between the “1” power level and the “0” power level. The operating voltage of many laser diodes can be approximately 3.3 V, and the modulation reference current as well as bias current may be incompatible with low power applications. As a result, data communication and/or communication via laser diode between components within a system may be hampered due to the power needs of a laser driving circuit.
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