More Reading

• When Shorter isn't Better, DesignCon 2010, Mike Steinberger + Cray.
• This was a long paper which built up to a very small conclusion.  The conclusion was sometimes you have resonant behavior which is hard to find and suggest a metric (unequalizable energy ) to maybe identify it.  Resonance is something which is easily attributed but hard to pin down.  I would have liked to see more insight into the problem and solution.  There was not mention of the attributed lengths and the wavelength of the fundamental frequency, no mention of loops in smith charts and no mention of Q factor.  If they used PDA they would have identified the worst case conditions before they built a whole system.
• Design of High Speed I/O Interfaces for High Performance Microprocessors, by Ankur Agrawal, Harvard Dissertation 2010.  Chapters 1 & 2.
• I found this paper when searching for information on clock recovery dithering noise.  It turns out to very interesting and very applicable to my current work.  I have only read chapters 1 and 2 which are the introductory sections but I am already impressed.  Overall it is well written and describes the problems of high speed I/O with clarity and precision.  His major contribution is a concept of collaborative timing recovery where for a multi-lane system you combine the CDR circuitry for area, power and accuracy improvement.  He also heavily references the CDR paper by Sonntag and Stonick which I have studied extensively.  His insights helped me understand it better.  Overall, I would recommend this as a good tutorial.
• An Introduction to Clock Recovery: Critical Aspects in Test and Measurement in High-speed Serial Designs.  Tektronix publication 2007.
• This was a fine primer on CDR concepts although sometimes they glossed over topics I wanted more on (derivation of jitter transfer function) and spent too much time on other topics (tabulating all the specs of various standards).  They had some pretty pictures and my favorite was one which showed the various stress jitter types used in testing a system.  Surprisingly they didn't even mention a specific Tek product to use.  Overall it is a good primer on the topic.

Crosstalk and Jitter

I have been learning a new signal integrity tool lately called Quantum Channel Designer (QCD) which has nothing to do with quantum behavior  . . .   but I digress.  I have been working on understanding how it works and why it works.  Here are some readings which I have done:  

• Comparison of BER Estimation Methods which Account for Crosstalk - DesignCon 2009 - Michael Steinberger, Barry Katz, Walter Katz, Todd Westerhoff.
• This is a nice paper but I would have liked a comparison to PDA.
• Exploration of Deterministic Jitter Distributions - DesignCon 2008 - Michael Steinberger and Christopher White.
• This paper had an interesting but flawed approach to discuss the jitter distribution of ISI and crosstalk.  But they did arrive at the conclusion that crosstalk roughly follows a bounded Gaussian distribution . . . since this agrees with my experience and research the flawed approach didn't bother me that much. :)
• Demonstration of SerDes Modeling using the Algorithmic Model Interface (AMI) Standard.  Designcon 2008, Michael Steinberger, Todd Westerhoff, Christopher White
• This was a fine introduction to AMI model usage but nothing ground breaking.  One good comment was on LTI analysis: 
• The very fact that the analysis takes so many different possible messages into account masks the effect of any one message.
• This is the problem/feature of statistical LTI analysis.
• Channel Compliance Testing Utilizing Novel Statistical Eye Methodology, DesignCon 2004, Anthony Sanders, Mike Resso, John D’Ambrosia.
• Wow!  This is a great paper and I can't believe that I haven't read it before.  This paper describes the algorithm behind StatEye (and QCD) and a statistical approach to calculate the Bit Error Ratio.  I would very much like to implement this so I can better understand it and to compare it to some of my own ideas on how to quickly calculate the BER.  I would highly recommend this paper.