Accelight’s QSFP56 transceiver module is designed for use in 200 Gigabit Ethernet links over 2km single mode fiber. The module has 4 independent electrical input/output channels operating up to 53.125Gbps per channel. This transceiver consists of one transmitter/receiver unit operating on a set of 4 wavelengths on the ITU G.694.2 CWDM grid near 1300nm. The transmitter path of the module incorporates a bidirectional PAM4 re-timer ASIC integrated with one 4-channel modulator driver, 4 directly modulated lasers and one optical multiplexer. On the receiver path, one optical de-multiplexers are coupled to 4 photodiodes and one 4-channel TIA arrays, along with the PAM4 re-timer. The electrical interface of the module is compliant with the 200GAUI-4 interface as defined by IEEE 802.3bs and SFF-8679.