100G 光模块 CFP2 LR4

HC 100G CFP2 LR4 optical Transceiver integrates receiver and transmitter path on one module. In the transmit side, four lanes of serial data streams are recovered, retimed, and passed to four laser drivers. The laser drivers control four EMLs (Electric-absorption Modulated Lasers) with center wavelength of 1296 nm, 1300nm, 1305nm and 1309 nm. The optical signals are multiplexed to a single –mode fiber through an industry standard LC connector. In the receive side, the four lanes of optical data streams are optically de-multiplexed by the integrated optical de-multiplexer. Each data stream is recovered by a PIN photo-detector and transimpedance amplifier, retimed. This module features a hot-pluggable electrical interface, low power consumption and MDIO management interface.

The module provides an aggregated signaling rate from 103.125 Gbps to 111.81 Gbps. It is compliant with IEEE 802.3-2012 Clause 88 100GBASE-LR4 and ITU-T G.959.1-2012-02, and OIF2010.404.08 CEI-28G-VSR electrical specifications. The MDIO management interface complies with IEEE 802.3-2012 Clause 45 standard. The transceiver complies with CFP MSA CFP2 Hardware Specification Rev. 1.0, CFP MSA Management Interface Specification Rev. 2.2, and OIF CEI-28G-VSR standards. A block diagram is shown in Figure 1.

Figure 1. CFP2 LR4 Optical Transceiver functional block diagram

Transmitter

The transmitter path converts four lanes of serial NRZ electrical data from line rate of 25.78 Gbps to 27.95 Gbps to a standard compliant optical signal. Each signal path accepts a 100 Ω differential 100 mV peak-to-peak to 900 mV peak-to-peak 25 Gbps electrical signal on TDxn and TDxp pins. Inside the module, each differential pair of electric signals is input to a CDR (clock-data recovery) chip. The recovered and retimed signals are then passed to a laser driver which transforms the small swing voltage to an output modulation that drives a EML laser. The laser drivers control four EMLs with center wavelengths of 1296 nm, 1300 nm, 1305 nm and 1309 nm. The optical signals from the four lasers are multiplexed together optically. The combined optical signals are coupled to single-mode optical fiber through an industry standard LC optical connector.

Receiver

The receiver takes incoming combined four lanes optical data from line rate of 25.78 Gbps to 27.95 Gbps through an industry standard LC optical connector. The four incoming wavelengths are separated by an optical de-multiplexer into four separated channels. Each output is coupled to a PIN photo-detector. The electrical currents from each PIN photo-detector are converted to a voltage with a high-gain transimpedance amplifier. The electrical output is recovered and retimed by the CDR chip. The four lanes of reshaped electrical signals are output to RDxp and RDxn pins.

Pin Function Definitions

Absolute Maximum Ratings

Low Speed Electrical Characteristics