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supermoment

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Jitter transfer BW spec
Apr 19^th, 2010, 7:05pm

I have one question about the OC192 jitter transfer spec in the page 15 of "Verification of Bit-Error Rate in Bang-Bang Clock and Data Recovery Circuits" article.

According to the diagram, the max jitter transfer bandwidth for OC192 is 8MHz. However, according to the Telcordia Technologies GR-253-CORE document, it states the jitter transfer BW is <120kHz with max peaking 0.1dB. Besides this, B. Razavi optical text book did mention this 120kHz BW, which is very difficult to meet (large filter). This spec is only valid when transmitting data from Rx to Tx or data generator/repeater).

I just want to know where is the source/papers talk about this max
jitter transfer BW is 8MHz. According to my knowledge, most of the CDR circuit in JSSC does not meet this criteria because this
BW is contradictory to jitter tolerance spec, which need BW >4MHz.

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Ken Kundert

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Silicon Valley

Re: Jitter transfer BW spec
Reply #1 - May 4^th, 2010, 11:20am

I have looked around and have been unable to find where I got the 8MHz number. I have also been unable to find support for the 120kHz number. This limit seems to be poorly documented in the open web. Would it be possible for you to send me the telecordia spec so that I can update the paper with the correct number.

Thanks,
-Ken

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supermoment Senior Member Offline Posts: 167	Re: Jitter transfer BW spec Reply #2 - May 4^th, 2010, 6:44pm have sent the document.
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Ken Kundert Global Moderator Offline Posts: 2384 Silicon Valley	Re: Jitter transfer BW spec Reply #3 - May 4^th, 2010, 10:31pm Thanks. I'll update the document to show the 120kHz number once I get a resolution on http://www.designers-guide.org/Forum/YaBB.pl?num=1272944729. -Ken
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Ken Kundert Global Moderator Offline Posts: 2384 Silicon Valley	Re: Jitter transfer BW spec Reply #4 - May 5^th, 2010, 11:12am I've decided not to wait. I have updated the paper with the correct numbers. -Ken
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supermoment Senior Member Offline Posts: 167	Re: Jitter transfer BW spec Reply #5 - May 20^th, 2010, 6:41pm There is another paper using jitter transfer of 8MHz. The journal paper from Intel: A CMOS 10-Gb/s SONET Transceiver Harish S. Muthali, Member, IEEE, Thomas P. Thomas, Member, IEEE, and Ian A. Young, Fellow, IEEE
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