Tired of waiting for your SPICE to finish?

By Patrick Carrier

Anyone who has ever had to simulate a SERDES interface knows how long it take to run a couple hundred bits through a SPICE model.  Hours.  Sometimes you have to kick it off overnight.  And if you want to do some solution space exploration, probably one of the main purposes for running your simulation, it could take you a whole week of sims.  I mean, you could take the time that your sim is running to go talk to your co-workers, but some of those guys aren’t all that fun to talk to.  😉  But there are better ways.

One of the best options is to use FastEye in HyperLynx.  It will run on your existing SPICE models, and gives you a lot more information than just your standard old bit-by-bit SPICE sim.  It uses pulse and step responses to characterize your SERDES channel and then uses that information to generate your eye diagrams.  And it generates eyes not only for the number of bits you are running, but also your target bit error rates.  Try simulating a trillion bits in SPICE and see how that works out… waiting half a million years for your sim to finish isn’t all that fun.  Especially if you don’t have solitaire installed on your machine.

You can read more about some of the new advancements in SERDES simulation in my recent article in PCD&F at:


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This article first appeared on the Siemens Digital Industries Software blog at