VSC82380 pages

VSC8238
www.vitesse.com
PRODUCT BRIEF
8 Gbps to 11.3 Gbps Advanced Electronic Equalization with
Limiting Amplifier and Clock and Data Recovery
Vitesse’s superior EDC now equalizes 8 Gbps to 11.3 Gbps signals in optical and copper environments
The VSC8238 device is a compact, fully integrated electronic dispersion
compensator (EDC) that provides clock and data recovery (CDR),
incorporating a sophisticated feed-forward equalization (FFE) and decision
feedback equalization (DFE) architecture. The device is designed to resolve
the most difficult compensation challenges across multiple optical and
copper applications.
The receive chain within the VSC8238 device incorporates a low-noise
automatic gain-controlled amplifier, a high-speed adaptive equalizer with
linear and nonlinear compensation, a jitter-tolerant clock and data recovery
unit, and a precision limiting amplifier.
The device includes a fully compliant XFI output interface. The equalizer
implementation provides a high level of signal impairment compensation to
ensure a robust link for a wide range of applications, from legacy
backplanes to optical 10GBASE-LRM. Superior overall performance
enables the VSC8238 to excel in legacy backplane data rate upgrades,
where the use of subrate connectors and PCB design practices can result in
poor system SNR and high levels of signal reflections. In the optical domain,
the VSC8238 is the only EDC that provides a wide margin to the
10GBASE-LRM specification, resulting in excellent module and system
manufacturing yields.
Highlights
• Superior equalization performance
• Supports data rates from 8 Gbps
to 11.3 Gbps
• Data protocol agnostic
Applications
• Legacy backplane data rate
upgrades from 3 Gbps to 10 Gbps
• XENPAK/X2 10GBASE-LRM
module
• Host cards for SFP+
10GBASE-LRM
• Host cards for SFP+ passive attach
copper cable links in excess of 15
meters
LTREF REF_SEL
Link
Monitor
REFCLK
EQ_OUT
Link
Monitor
SPI or Parallel
Interface
RSTN To Microcontroller
LF
(Ext Cap)
AGC_IN AGC Equalizer, Limiting Amplifier, Clock and Data Recover y
RXLOL
VSC8238
Functional Block Diagram