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eye diagram (Read 15953 times)
analog_cha
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eye diagram
Jul 11th, 2008, 1:33am
 
hi All,
Can any body tell how i can write the ocean command to measure the jitter from the eye diagram??
I am aware of measuring it from the plot. But not able to automate it.

Thanks.
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sheldon
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Re: eye diagram
Reply #1 - Jul 11th, 2008, 7:17pm
 
Analog_cha,

  Have you tried the jitter_meter from the bmslib? It calculates
the jitter directly from the transient output using a reference clock.

                                                      Best Regards,

                                                         Sheldon
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analog_cha
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Re: eye diagram
Reply #2 - Jul 13th, 2008, 8:01pm
 
Dear Sheldon,

I have never heard about bmslib and jitter meter.  How is it related to ocean scripting??
Could you share some more info about it.
I am not able to get any thing even after googling.

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jbdavid
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Re: eye diagram
Reply #3 - Jul 15th, 2008, 11:40am
 
It doesn't relate to ocean scripting, and It ASSUMES you are running Cadence tools.. -- a full install of which will have a copy of "bmslib".

you place the "jittermeter" model in your schematic.. and run the simulation.. If I recall correctly It captures a number of periods of the input signal and calculates some statistics on the variation in the period. (or did it need a reference clock? )

-- but my concerns have been more with validation of pll operation than measuring the jitter.. usually the designers do that..
--
But I find I can do a heck of a lot of results analysis in a verilogA model, rather than hoping to find a way to post process the results and get the right answer.
jbd
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jbdavid
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Andrew Beckett
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Re: eye diagram
Reply #4 - Jan 2nd, 2009, 4:06pm
 
You may find the attached SKILL useful. See Sourcelink solution 11395772 too which gives the same code, but with some additional notes.

Andrew.


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apprentice
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Re: eye diagram -
Reply #5 - Apr 4th, 2011, 8:21pm
 
how to setup source and analysis for PRBS with spectre?

Assume a  transmission line or its S-parameter data to be tested,  wanted to simulate eye diagram  at the output of it.

thanks
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ywguo
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Re: eye diagram
Reply #6 - Apr 12th, 2011, 7:24pm
 
Hi apprentice,

Obviously you have another independent question, you'd better to start a new post in this forum.


Here is a good article that can answer your question.
http://www.designers-guide.org/Modeling/JTOL_rev1.0.pdf


Best Regards,
Yawei
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apprentice
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Re: eye diagram
Reply #7 - Apr 13th, 2011, 8:17pm
 
thanks.
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