Accelight ACP2C-ER4 optical transceiver is designed for 100G links over 40km single mode fiber. It is compliant with IEEE 802.3-2012 Clause 88 100GBASE-ER4, CFP MSA CFP2 Hardware Specification Rev. 1.0, CFP MSA Management Interface Specification Rev. 2.2, and OIF CEI-28G-VSR standards. The transmitter integrates 4 EMLs with center wavelength of 1295.96 nm, 1300.05nm, 1304.58nm and 1309.14 nm. The 4 optical signals are multiplexed into one single mode fiber. On the receive side, the four lanes of optical data streams are optically amplified (SOA) and de-multiplexed. And each data stream is recovered by a PIN photo-detector and trans-impedance amplifier. It has a built-in CDR, and a MDIO management interface based on the CFP MSA CFP2 Hardware Specification Rev. 1.0 and CFP MSA Management Interface Specification Rev. 2.2 requirements.