QSFP112 400G transceiver module is designed for use in 400G Ethernet links up to 50m over OM4 and 30m over OM3 multi-mode fiber. The module has 4 independent electrical input/output channels operating at 106.25Gbps per channel. This transceiver consists a transmitter/receiver unit operating on 850nm wavelengths. The transmitter path of the module incorporates a PAM4 re-timer ASIC integrated with a 4-channel modulators driver, 4 externally modulated lasers. On the receiver path, there are 4 photodiodes and one 4-channel linear TIA arrays, along with the PAM4 re-timer. The electrical interface of the module is compliant with the 400GAUI-4 interface as defined by IEEE 802.3ck.