AN 835: PAM4信令基础

ID 683852
日期 3/12/2019
Public
文档目录

1.3.3. LR (Long Reach) - Chip to Chip Across a Backplane/Midplane or a Cable(LR(长距离)-背叛/中板或者电缆上的芯片到芯片)

图 8. LR互连

此接口可在机架内的背板或中间板的两个卡之间进行通信,并且小于1米,最多可连接两个连接器。KP-FEC可能是一个满足BER的要求。

表 2.  CEI 56G不同范围和距离的汇总
参数 Ultra Short Reach (USR) Extra Short Reach (XSR) VSR MR LR
Reach 2.5D/3D Chip- to-optics Engine Chip- to-module Chip-to-chip Chip-to-chip over a backplane
Data Rate (Gbps) 19.6-58 39.2-58 39.2-58 36-58 36-58
BER (pre-FEC) 1E-15 1E-15 1E-6 1E-6 1E-4
Distance 10 mm (~0.4") 50 mm (~2") 150 mm (~6") 500 mm (~20") 1000 mm (~40")
Interconnect MCM PCB+0 connector PCB+1 connector PCB+1 connector PCB+2 connectors
Insertion Loss (dB) 2@28 GHz (NRZ) 4@14 GHz (PAM4) 10@14 GHz (PAM4) 20@14 GHz (PAM4) 30@14 GHz (PAM4)
Modulation NRZ PAM4 or NRZ PAM4 or NRZ PAM4 or NRZ PAM4 or ENRZ
FEC No No Yes/No Yes/No Yes/No
表 3.  Ethernet 50G/通道标准的汇总
Reach 400GBE (802.3bs) 200GBE (802.3bs, .cd) 100GBE (802.3cd) 50GBE (802.3cd)
Chip-to-chip (C2C) and Chip-to-module (C2M) 400GAUI-8 200GAUI-4
Backplane (BP) 200GBASE-KR4 100GBASE-KR2 50GBASE-KR
Copper Cable (CC) 200GBASE-CR4 100GBASE-CR2 50GBASE-CR