Zhangkun, A typical serial link like PCIE, GE have a PLL on the TX side and a clock data recovery circuit (CDR) on the RX side. The TX PLL multiply the reference clock up and latch data out. In a lot serial links, data is 8B/10B encoded to ensure enough transition edges for the CDR to recover the clock. In that sense, the clock is "embedded". The CDR on the RX side will try to figure out the right timing to sample data based on the data transition it was seeing. The CDR fundamentally is another PLL, the loop inside the CDR move the sampling edge back and forth to have it centered around the center of the data eye, thus recovering or "de-embeding" the clock and use the recovered clock to latch in data. Wei -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx on behalf of Zhangkun Sent: Tue 4/4/2006 8:51 PM To: si-list Subject: [SI-LIST] How to embedded and to deembedded the clock to serial signal, such as GE and PCI-E Dear all Recently, in our product, there is some problem in our product. The serial signal, such as GE and PCI-E, has error bits. We have found out the reason: 1.The serial signal has crosstalk. 2.The clock signal to PLL has crosstalk. 3.The analog power of the PLL or the serial signal driver has large power noise. I guess the basic reason is that the jitter of clock. Could anybody explain to me how the clock signal is embedded to and deembedded from the serial signal? Best Regards Zhangkun 2006.4.5 ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu