Karan, FYI. You can find more information, technical articles, licensing contacts, and SSCG vendors at Lexmark's web page. http://www.lexmark.com/US/corporate/sscg/index.html Regards, Brandon "Istvan NOVAK" <istvan.novak@xxxxxxxxxxxxxxxx>@freelists.org on 09/05/2003 07:36:54 AM Please respond to istvan.novak@xxxxxxxxxxxxxxxx Sent by: si-list-bounce@xxxxxxxxxxxxx To: <kbagga31@xxxxxxxxx>, <si-list@xxxxxxxxxxxxx> cc: Subject: [SI-LIST] Re: (EMI)spread spectrum clocking Karan, The spread spectrum solution puts up to a few percent of frequency modulation on the clock signal, with a low (10-100kHz) repetition frequency. As long as the clock PLLs/DLLs in the system dont remove this modulation, and assuming that the system timing allows for this modulation, it spreads the energy of the clock over a wider spectrum and it becomes less disturbing subjectively for instance to broadcast audio and video programs. The measured peak interference also goes down, because legal compliance measurements have to be taken with a pre-determined bandwidth: if you spread the spectrum of the clock over a wider frequency band, the energy falling into the measurement bandwidth will also be less. Regards, Istvan ----- Original Message ----- From: "karan bagga" <kbagga31@xxxxxxxxx> To: <si-list@xxxxxxxxxxxxx> Sent: Friday, September 05, 2003 6:09 AM Subject: [SI-LIST] (EMI)spread spectrum clocking > Hi Experts > > I want to know the fundamental physics behind spread spectrum clocking. > How does modulating the clock frequency helps reducing EMI ? > > Thanks & Regards > Karan > > --------------------------------- > Do you Yahoo!? > Yahoo! SiteBuilder - Free, easy-to-use web site design software > > ------------------------------------------------------------------ > 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 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 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 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