It’s hard to beat plug & play as a hot
buzzword over the past few years.
Often, the term conjures up images of
Microsoft Windows. Now, Altera is getting
into the mix with Plug & Play Signal
Integrity. The company’s hot-swappable
FPGA device uses low-power linear adaptive
equalization technology—Altera’s
Adaptive Dispersion Compensation
Engine (ADCE).
Plug & Play Signal Integrity gives system
architects hot-socketable Stratix II
GX FPGAs that monitor signal quality and
compensate for degradation in multigigabit
system interconnects caused by a
variety of typical conditions, including
manufacturing, voltage, temperature,
and design variations.
It beefs up signal integrity by continuously
adjusting equalizer settings for up
to 20 receivers to provide the best eye
opening for non-return-to-zero (NRZ) signals
operating between 2.5 and 6.375
Gbits/s (see the figure). The end result is
improved system reliability and performance,
as well as reduced bit
error rate (BER).
When hot-swapping a card
configuration in a backplane,
the ADCE monitors signals with
up to –17 dB of interconnect
loss at the Nyquist frequency
and adjusts the receiver’s
equalizer for maximum eye
opening without typically
requiring any pre-emphasis. Yet
because Altera’s Stratix II GX
devices were built with signal
integrity in mind, the combination
of ADCE and pre-emphasis
generally results in very low
BER operation for systems with
up to –27 dB of loss.
With the technology, users can
design their systems with universal
cards that plug into any position in a
backplane. The implications include
fewer card types, increased flexibility,
and reduced maintenance and testing
since characterization of each card slot
for the optimal signal integrity will no
longer be necessary.
“Altera continues to deliver FPGA
transceiver innovation to customers by
providing system designers with the only
plug-and-play signal-integrity capability
available in an FPGA,” said Danny Biran,
senior VP of product and corporate marketing
at Altera.
“Our FPGAs’ ability to plug into a powered
system and automatically adjust to
varying system and environmental conditions
allows our customers to reduce
inventories, simplify maintenance procedures,
and shorten time-to-market,” he
continued. “The ADCE itself significantly
reduces the tedious characterization
effort that is the result of high-speed systems
having varying link characteristics
across card slots.”
For more information, refer to the white
paper “Digitally Assisted Adaptive Equalizer
in 90 nm With Wide Range Support
From 2.5 Gbps to 6.5 Gbps” by Wilson
Wong, et al., Altera Corp., April 2007.
Altera Corp.
www.altera.com
