Hello Johann, Vdiff is the voltage difference between the pos and the neg input. Vdiff = Vpos - Vneg suppose you have a signal voltage on the pos pin of 1.6V and the neg pin of 1.2V this would result in a Vdiff of 0.4V suppose a signal voltage of the pos pin of 0.125V and the neg pin of -0.125V this would result in a Vdiff of 0.25V hope this makes it clear regards Eckhard Mit freundlichen Grüßen / Best regards / Cordiali saluti / ystävällisin terveisin Eckhard Lenski Nokia Siemens Networks GmbH & Co. KG COO RA GERD BTS BR PDev CAE Lib&IBIS CAE libraries and models Balanstr. 59 81541 München Germany phone : +49 89 636 79002 fax : +49 89 636 78895 email: eckhard.lenski@nsn.com <mailto:eckhard.lenski@nsn.com> http://www.nokiasiemensnetworks.com/ibis Nokia Siemens Networks GmbH & Co. KG Sitz der Gesellschaft: München / Registered office: Munich Registergericht: München / Commercial registry: Munich, HRA 88537 WEEE-Reg.-Nr.: DE 52984304 Persönlich haftende Gesellschafterin / General Partner: Nokia Siemens Networks Management GmbH Geschäftsleitung / Board of Directors: Lydia Sommer, Olaf Horsthemke Vorsitzender des Aufsichtsrats / Chairman of supervisory board: Lauri Kivinen Sitz der Gesellschaft: München / Registered office: Munich Registergericht: München / Commercial registry: Munich, HRB 163416 ________________________________ From: owner-ibis-users@eda.org [mailto:owner-ibis-users@eda.org] On Behalf Of ext Nittmann, Johann Sent: Thursday, February 26, 2009 5:56 PM To: ibis-users@eda.org Subject: [IBIS-Users] How is Vdiff defined ? Does Vdiff=250mV mean +- 125mV or +-250mV? Dear all, Could somebody explain how the value of Vdiff is defined? Does Vdiff=250mV mean +-125mV or +-250mV! According the IBIS cookbook-v4, at page 73 where it says "For example, an active-high buffer with a vdiff of 100 mV will be considered high if the non-inverting pin is at least 100 mV above the inverting pin. " I would expect it to be defined as +-125mV but one our SI tool provider is defining it at +-250mV? Thanks, Johann Johann Nittmann Principal Engineer Cavium Networks 100 Nickerson Road Marlborough, MA 01752 Tel: 508 683 8869 -- This message has been scanned for viruses and dangerous content by MailScanner <http://www.mailscanner.info/> , and is believed to be clean. -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. -------------------------------------------------------------------- |For help or to subscribe/unsubscribe, e-mail majordomo@eda-stds.org |with the appropriate command message(s) in the body: | | help | subscribe ibis <optional e-mail address, if different> | subscribe ibis-users <optional e-mail address, if different> | unsubscribe ibis <optional e-mail address, if different> | unsubscribe ibis-users <optional e-mail address, if different> | |or e-mail a request to ibis-request@eda-stds.org. | |IBIS reflector archives exist under: | | http://www.eda-stds.org/pub/ibis/email_archive/ Recent | http://www.eda-stds.org/pub/ibis/users_archive/ Recent | http://www.eda-stds.org/pub/ibis/email/ E-mail since 1993Received on Fri Feb 27 01:20:42 2009
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