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use o-scope to measure jitter

Rookie

Hello from Ottawa, Canada

Rookie

HI, this class (Part II) is audo archived (see the player above) and the slides have been updated (under special educational materials). Enjoy!

Blogger

Would like to know how change in phase due to rduction in inductance over frequency causes ISI??

Rookie

Thanks everyone! See you tomorrow.

Blogger

Thanks for the information.

Rookie

"See" you tomorrow!

Remember to enjoy what you're doing.

FYI, if you missed anything, the audio from today is now archived.

Blogger

Hemanshu, here's a paper I did for Anritsu that discusses crosstalk in these kinds of systems: http://cancomdigital.com/resourcecenter/AssetsRC/AnritsuExtremeDataRatesWhitepaper.pdf

 

I guess now the trigger is limited to 16GHz :)

Rookie

Right, Danny, that's what I meant, the built in tools are limited, need to bring in test instruments for some diagnostics. DCA has always done fine with its pattern trigger and the addition of triggering on bit sequences is great... when will you have a new, high sampling rate mainframe? Or did I miss that release?

I agree that total jitter and eye height are the key to a good analysis

Rookie
We'll get those corrected slides up ASAP @patrice.bedford; hopefully this afternoon.
Blogger

Hi Hemanshu,

1. FEXT is usually a bigger problem for multi-lane high speed serial systems, like 100 GbE. The aggressor propagating in the opposite direction of the victim aggravates the signal more.

2. I'll dig up a paper that discusses sync and async crosstalk for you. (digging...)

I have in mynd Agilent's last version of DCA-X

Rookie

When I say that "only errors count" what I mean is that the BER is the ultimate judge of performance. If the BER is acceptable, move along. When it's not, then get to work. Certainly including analaysis of clock recovery performance/response!

Ransom, this in not totally true. We can analyze non PRBS patterns, since it's now possible to trig on a sequence of bits and not a pattern.

Rookie

Could you please point to some application note/tutorial pointing to Asynchronous and synchronous Crosstalk behavior and thier signatures?

Built in tools have the advantage of grabbing the signal without introducing cables, connectors and all the systematics associated with them, but are usually limited in flexibility, for example, ability to use non PRBS test patterns

I agree the mask tests are statistical limitations

Rookie

In slide 22 you mentioned that "FEXT is usually worse than NEXT". I believe this depends on how the signals are routed and their stackup. do you agree?

The combination of total jitter at a BER and eye height at a BER can really tell you what's going on, though it's subject to the same statistical limitations as mask testing...

There's so much more to the "only errors count" related to jitter if you care about the quality of the recovered clock... if you are designing/testing a CDR or a SERDES architecture - then you need to consider the spectral contents of jitter, esp. low frequency ones - which are extremely hard to be measured propperly...

Rookie

In my experience built in tools are the most accurate just because we can get the histograms analyzed by the processor

Rookie

Hi Danny, I like anything that gets you closer to the bit error ratio/rate.

OMA is good, eye-height is better. We'll do that tomorrow, eye-height as a function of BER.

Probably as true as the Dirac Delta model of jitter because I think that is what all jitter software use to separate the jitter components

Thanks for the presentation once again!

Rookie

We use built in tools froma gilent scopes

 

Nce dive through the concepts..!!

 

Rookie

Thanks Ransom for this lecture. Nowadays we started to use OMA (optical modulation amplitude) because what matters is not the level on a logic 1 or 0, but the ability of a receiver to distinguish a 1 from 0. What do you think about this approach?

Rookie

I see one person using built in tools, anyone else?

Well done ,audio was much better today

Rookie

By "ture", I meant "true" to wit:

compared to the "true" value of jitter, how close do you think your equipment gets you?

Thanks for the lecture.  :-)

Rookie

That is, compared to the "ture" value of jitter, how close do you think your equipment gets youy?

 Thanks  great talk

Rookie

Scope  Excellent; Thanks very much Ranson and Janine!

Rookie

Thanks a lot for the nice lecture.

Rookie

Over the last decade the scope jitter analysis software has come a long way. We get mostly consistent answers from different vendors, which is comforting. How accurate do you think your jitter measurements are?

 

good presentation Bye from TO

Theo HAVE A GREAT DAY

Rookie

ASSET InterTech's HSIO tool measures jitter using the embedded tools within the processors.  We use JTAG to utilize these tools.  This is how we look at the jitter in high-speed signals. 

 

Rookie

Could you please point to some application note/tutorial pointing to Asynchronous and synchronous Crosstalk behavior and thier signatures

Will slides with corrections to the symbols be posted?

I see lots of jitter analysis on scopes with software additions and a handful of BERT analyses.

Scope. Thanks Ransom and Janine.

Rookie

Thanks Ransom and Janine!

 

Rookie

Thank you for Today's lecture Ransom and Janine

Rookie

JBERT,Parbert, and EZjit from agilent

real time scopes with jitter analysis software and J-BERTs

Using Real-Time Scope Lecroy SDA825Zi 25GHz

Rookie

I use the built-in Jitter tool from Tek

Rookie

Any tutor for measuring jitter? thanks

 

Rookie

Jitter analyzer software on Scope

 

Rookie

I measure jitter using my scope.

period to period jitter via LeCroy WaveRunner 204MXi 2GHz 10GS/s

measuring using scope (DCA)

Rookie

wide band oscilloscopes, DCA-J Bert

Rookie

MP1800A system based on Error Detector Bathtub curves.

Why do you say that FeXT is worse than NeXT?  Don't the Inductive and Capacitive Coupling Terms cancel out for FeXT, assuming an Embedded Stripline? 

Rookie

boxes are minimized when opened in foxit reader

 

Rookie

is box an arrow again?

 

Rookie

google impulse response!!

Rookie

but I do get it about the smeared impulse.

 

Rookie

both frequency n time.. depends on the what we are trying to describe

 

Rookie

why inductance is reduced due to skin effect?

 

Rookie

I hop back and forth between domains. I use a zip line to traverse between domains.

On which slide are we?

Rookie

FYI this does not play in IE10 unless you press F12 and put the browser in IE9 mode

Rookie

Hello from Monterrey,Mexico

Rookie

Hello everyone Bremen, Gr

Rookie

I have been on a zip-line....

Rookie

ZIP LINE, YES up in NH mountain, Wild

Rookie

Hello from Milwaukee!

Rookie

Treetop obstacle course with zip lines in the Poconos.

Hello everyone from Bremen, Gr

Rookie

Hello fromm Ottawa

 

Rookie

here we go audio is good!

Rookie

Cloudy evening in Eindhoven here 

Rookie

Greetings from Toronto

Theo

Rookie

Foggy here in Petaluma. Will be crystal clear by the end of our class, though.

Good morning from Toronto.

Rookie

Hi All; Good Morning from Cloudy Boston.

Rookie

Greetings!

I just ran through the slides, we have some nasty pdf conversion issues in this set. Lots of important symobls converted to boxes. We'll talk.

Aplogies for the "rookie" title next to your log in. Anyone attending a course on signal integrity is far beyond rookie!

Blogger

Welcome! The streaming audio player will appear on this web page when the show starts at 12:00 pm  Eastern today. Note however that some companies block live audio streams. If when the show starts you don't hear any audio, try refreshing your browser.

Blogger

Good Morning from cloudy Boston

Rookie

Good morning from Panama City, FL.

Rookie

Good evening from Valladolid, Spain; we don´t have Olimpic Games but have Rafa Nadal, winner of tennis US Open :-)

Be sure to click 'Today's Slide Deck' under Special Educational Materials above right to download the PowerPoint for today's session.

Blogger


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