Venu, Fanout is a DC loading concept for TTL. It has no meaning when talking about high speed circuits. Driver output impedance and rise time are what are important for COMS. CMOS inputs are purely capacitive, so they represent no DC load. TTL is dead as a technology, so worrying about fanout is behind us. By the way, ECL is dead as well. Lee W. Ritchey Speeding Edge P. O. Box 2194 Glen Ellen, CA 95442 Phone- 707-568-3983 FAX- 707-568-3504 I just used the energy it took to be angry to write some blues. Count Basie > [Original Message] > From: Ummalaneni, Venu Babu (Venu) <venubabu@xxxxxxxxx> > To: <si-list@xxxxxxxxxxxxx> > Date: 2/3/2005 10:11:18 PM > Subject: [SI-LIST] Fan-out in TTL and CMOS > > Hi Experts, > > I know that fan-out in TTL circuits is decided by noise margin, i.e.; if > we want more fan-out noise margin has to diminishes. > > In case of CMOS which factor decides the fan-out. As there is no static > current drawn by the load, I hope time delay will decide the fan-out in > case of CMOS. > > Please clear me if I am wrong. Any inputs are welcome. > > > Thanks in advance > > Best Regards, > Venu. > ------------------------------------------------------------------ > 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