Sep 25 – 29, 2006
Valencia, Spain
Europe/Zurich timezone

Evaluation of Data Transmission at 80MHz and 160MHz Over Backplane, Copper and Optical Links

Sep 27, 2006, 4:20 PM
1h 40m
Valencia, Spain

Valencia, Spain

IFIC – Instituto de Fisica Corpuscular Edificio Institutos de Investgación Apartado de Correos 22085 E-46071 València SPAIN


Mikhail Matveev (Rice University)


The results of data transmission tests over custom backplane, copper and optical links at a multiples of the LHC bunch clock frequency are presented. We have evaluated a parallel data transmission at 80MHz and 160MHz using the GTLP and LVDS standards as well as serial copper and optical links operating at 3.2Gbps.


The bunch clock frequency of the LHC accelerator at CERN is specified at
40.07897 MHz. Most of the LHC experiments will utilize this frequency (or its
multiples or derivatives) as the main frequency of data transmission for their
Trigger and DAQ electronic systems. For example, the triggering system of the
Cathode Strip Chamber (CSC) Endcap Muon sub-detector at the CMS experiment
utilizes data transmission at a doubled LHC frequency for most of its data paths,
including the LVDS links from an on-chamber electronics to peripheral crates;
custom peripheral and Track Finder GTLP backplanes; optical links between the
peripheral and Track Finder crates.

  A proposed  Super-LHC (SLHC) upgrade with increase of the operating frequency

will be challenging for many synchronous data transmission systems. The goal of
this work was to evaluate possible solutions for data transmission at 80MHz and
160MHz suitable for the SLHC era. We have used an existing hardware designed for the
CSC electronic system for the evaluation of data transmission at 80MHz and 160MHz
using the LVDS and GTLP logical standards. We have designed a new evaluation board
to study the optical and copper links operating at 3.2Gbps. The results of
measurements and possible solutions are presented.

Primary authors

Mikhail Matveev (Rice University) Mr Paul Padley (Rice University) Mr Sang-Joon Lee (Rice University)

Presentation materials