ADI LDD features dual loop control

The ADN2870 3.3Gbps laser diode driver (LDD) from Analog Devices Inc. (ADI) is fully compliant with the Small Form Factor Pluggable (SFP) Multisource Agreement (MSA) and digital diagnostics (SFF-8472) specifications. The company claims it is the only SFP compliant LDD to feature dual loop control of average power and extinction ratio. This feature enables automatic laser control without temperature calibration and look up tables resulting in significant cost advantages.

The voltage input set points of the ADN2870 eliminate the need to use a separate precision digital potentiometer for calibration, and the LDD can interface directly to a common MicroConverter IC, typically used as a supervisor within modules.

When combined with other SFP compliant ICs from the company, the LDD can be used as part of a complete optical transmitter chipset for the MSA market. It is suitable for modules that serve SONET OC-48, SDH STM-16, 1X and 2X Fiber Channel, and GbE. The ADN2870 is priced at $6.95 in 1,000-piece quantities.