The SY88905 is an integrated Laser Diode controller for the SY88902 Laser Driver and SY88903 Laser Receiver that provides power control functions for a complete module solution. The SY88905 is designed to provide the laser diode with an independent DC threshold current (IBIAS) source to assure optimum laser diode performance. The SY88905 also provides buffered Loss-of-Signal (LOS) output in PECL level. The device is designed for fast and accurate calibration of the laser diode. Once the optimal operating point is determined and set for a specific laser diode, the threshold current (IBIAS) is designed to automatically compensate for laser diode aging and module temperature.