The transmission speed of 40 Gbit/s is the highest commercially-available rate that uses the simple light on/off keying or serial transmission scheme. CFP transceivers and 300-pin MSA transceivers are widely available for the 40 Gbit/s serial application.

In addition to ITU-T 40G serial transmission standards, VSR2000-3R2 for 2 km and P1I1-3D1 for 10 km, the IEEE defined a 40 Gbit/s serial interface for 2 km (40GBASE-FR). The demand for 40G serial transmission is growing in the fields of telecommunications as well as data and IP communications.

In today’s 300-pin MSA and CFP transceiver module market, XLMD-MSA TOSAs and ROSAs are widely adopted. With the introduction of the CFP2/4 MSA, thin, miniature TOSAs and ROSAs are essential for downsizing the pluggable transceiver modules.

The XLMD2-MSA aims to establish compatible sources of 40 Gbit/s miniature optical transmitter and receiver devices embedded into the compact 40 Gbit/s serial pluggable optical transceiver modules. Companies adopting the XLMD2-MSA will promote MSA-compliant products in order to meet customer demand and expand the market.

The XLMD2-MSA specifications include mechanical dimensions, interfaces with a common printed circuit board (PCB) design, pin assignment and electrical characteristics for the following compatible optical devices:

1.   (1) Cooled EMwL TOSA with built-in driver IC;

2.   (2) Cooled EMwL TOSA;

3.   (3) Cooled DML TOSA;

4.   (4) Uncooled DML TOSA; and

5.   (5) PIN-TIA ROSA