ADN2847

a FEATURES 50 Mbps to 3.3 Gbps Operation Single 3.3 V Operation Typical Rise/Fall Time 80 ps Bias Current Range 2 mA to 100 mA Modulation Current Range 5 mA to 80 mA Monitor Photodiode Current 50 ␮A to 1200 ␮ A Dual MPD Functionality for DWDM 50 mA Supply Current at 3.3 V Closed-Loop Control of Power and Extinction Ratio Full Current Parameter Monitoring Laser Fail and Laser Degrade Alarms Automatic Laser Shutdown, ALS Optional Clocked Data Supports FEC Rates 48-Lead (7 mm ؋ 7 mm) LFCSP Package 32-Lead (5 mm ؋ 5 mm) LFCSP Package Available in Die Form 3 V Dual-Loop 50 Mbps to 3.3 Gbps Laser Diode Driver ADN2847 APPLICATIONS SONET OC-1/3/12/48 SDH STM-0/1/4/16 Fibre Channel Gigabit Ethernet DWDM Dual MPD Wavelength Control GENERAL DESCRIPTION The ADN2847 uses a unique control algorithm to control both average power and extinction ratio of the laser diode, LD, after initial factory setup. External component count and PCB area are low as both power and extinction ratio control are fully integrated. Programmable alarms are provided for laser fail (end of life) and laser degrade (impending fail). Optional dual MPD current monitoring is designed into the ADN2847 specifically for DWDM wavelength control. FUNCTIONAL BLOCK DIAGRAM IMPDMON2 DEGRADE IMPDMON IMMON IBMON VCC CLKSEL GND FAIL ALS VCC IMODN VCC LD IMODP VCC MPD IMPD IMOD IMPD2 CONTROL GND PSET IBIAS GND ERSET DATAP DATAN CLKP CLKN IBIAS ASET ADN2847 GND GND ERCAP PAVCAP IDTONE LBWSET GND GND REV. 0 Informa...