80KSBR200 Datasheet, PDF (124/172 Pages) Integrated Device Technology – sRIO SERIAL BUFFER FLOW-CONTROL DEVICE

IDT 80KSBR200
Notes
Advanced Datasheet*
To illustrate these definitions using real values, consider the case of a CML (Current Mode Logic) transmitter that has a
common mode voltage of 2.25 V and each of its outputs, TD and TD, has a swing that goes between 2.5V and 2.0V. Using
these values, the peak-to-peak voltage swing of the signals TD and TD is 500 mV p-p. The differential output signal ranges
between 500 mV and -500 mV. The peak differential voltage is 500 mV. The peak-to-peak differential voltage is 1000 mV p-
p.
13.3 Equalization
With the use of high speed serial links, the interconnect media will cause degradation of the signal at the receiver.
Effects such as Inter-Symbol Interference (ISI) or data dependent jitter are produced. This loss can be large enough to
degrade the eye opening at the receiver beyond what is allowed in the specification. To negate a portion of these effects,
equalization can be used. The equalization technique implemented in the SerB is Pre-emphasis on the transmitter (under
register control)
13.4 Explanatory Note on Transmitter and Receiver Specifications
AC electrical specifications are given for transmitter and receiver. Long run and short run interfaces at three baud rates
(a total of six cases) are described.
The parameters for the AC electrical specifications are guided by the XAUI electrical interface specified in Clause 47 of
IEEE 802.3ae-2002.
XAUI has similar application goals to serial RapidIO^TM. The goal of this standard is that electrical designs for serial
RapidIO^TM can reuse electrical designs for XAUI, suitably modified for applications at the baud intervals and reaches
described herein.
13.5 Transmitter Specifications
LP-Serial transmitter electrical and timing specifications are stated in the text and tables of this section.
The differential return loss, S11, of the transmitter in each case shall be better than
-10 dB for (Baud Frequency)/10 < Freq(f) < 625 MHz, and
-10 dB + 10log(f/625 MHz) dB for 625 MHz <= Freq(f) <= Baud Frequency
The reference impedance for the differential return loss measurements is 100 Ohm resistive. Differential return loss
includes contributions from on-chip circuitry, chip packaging and any off-chip components related to the driver. The output
impedance requirement applies to all valid output levels.
The 80KSBR200 satisfies the specification requirement that the 20%-80% rise/fall time of the transmitter, as measured
at the transmitter output, in each case have a minimum value 60 ps.
Similarly the timing skew at the output of an LP-Serial transmitter between the two signals that comprise a differential
pair not exceed 25 ps at 1.25 GB, 20 ps at 2.50 GB and 15 ps at 3.125 GB.
Figure 25 Short Run Transmitter AC Timing Specifications - 1.25 GBaud
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March 19, 2007
„2005 Integrated Device Technology, Inc. All rights reserved. Advanced Datasheet for informational purposes only. Product specifications subject to change without notice.NOT AN OFFER FOR SALE The information presented herein is subject to a
Non-Disclosure Agreement (NDA) and is for planning purposes only. Nothing contained in this presentation, whether verbal or written, is intended as, or shall have the effect of, a sale or an offer for sale that creates a contractual power of acceptance.