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VSC7142 Datasheet, PDF (2/2 Pages) Vitesse Semiconductor Corporation – Dual Repeater/Retimer for Fibre Channel and Gigabit Ethernet
VSC7142
VSC7142 Dual Repeater/Retimer for Fibre Channel and Gigabit Ethernet
GENERAL DESCRIPTION:
The VSC7142 contains two FibreTimer Repeater /Retimer
cells and Signal Detect Units (SDUs) primarily used for
bidirectional signal clean up applications. Each FibreTimer
cell contains an all-digital clock recovery unit which can be
configured as either a Repeater or a Retimer. Repeaters
recover the incoming signal and retransmit the data
synchronously to the recovered clock in order to attenuate jitter so that downstream
devices see high amplitude, low jitter signals. Retimers eliminate jitter transfer by
retiming the recovered data to the local reference clock. An add/ drop FIFO inserts or
deletes 40-bit Fibre Channel Fill Words to match the incoming data rate to the local
reference clock, thereby ensuring Fibre Channel compliance at the output of the
Retimer. The VSC7142 also operates as a Repeater for Gigabit Ethernet applications at
1.25 Gb/s. Retimer mode is not available for Gigabit Ethernet applications.
MULTI-NODE SWITCH APPLICATION:
One application for the VSC7142 is in high port-count Fibre Channel and Ethernet
systems, such as switches. The following diagram shows a switch with a CMOS
protocol ASIC with integrated Serializer/Deserializers (SerDes) located on the Switch
Fabric card. Serial data from the protocol ASIC passes through multiple connectors
and long traces on the PCB before reaching the connector. Without the VSC7142, the
signal quality at the connectors would result in poor system performance. However,
by using the VSC7142, signal quality is ensured to meet the specifications of Fibre
Channel standards at the system interface connectors.
Port 1
Port N
Switch ASIC
Switch Fabric Card
C onnectors
Backplane
VSC7142
FibreTimer0 >
< FibreTimer1
Li ne Card
Fibre Channel Switch
For more information on Vitesse Products visit the Vitesse web site
at www.vitesse.com or contact Vitesse Sales at (800) VITESSE
or sales@vitesse.com
©2003 Vitesse Semiconductor Corporation
741 Calle Plano
Camarillo, CA 93012, USA
Tel: +1 805.388.3700
Fax: +1 805.987.5896
www.vitesse.com