Ling Li, Regarding: "it has no difference between the simulation on C_comp 0.1pF and 50pF". That's correct (for the case when the buffer model is driving), and that's the way HyperLynx 9.0 should also behave. Thanks, Arpad ====================================================================== From: Ling Li Ong [mailto:llong@altera.com] Sent: Wednesday, September 04, 2013 2:19 AM To: Muranyi, Arpad; ibis-users@eda.org Cc: Siong Hee Lim Subject: RE: Role of C_comp Hi Arpad, Thanks for your fast response. I was referring to the mentor's website which commented with using the version 8.2.1, it has no difference between the simulation on C_comp 0.1pF and 50pF. This version may be outdated compare to latest as I noticed the posting date was on last year. However, I assume it should perform the same simulation result after this version. http://communities.mentor.com/mgcx/thread/6935 May I know is this comment align to your understanding? Thanks. Regards, Ling Li From: Muranyi, Arpad [mailto:Arpad_Muranyi@mentor.com] Sent: Wednesday, September 04, 2013 2:46 PM To: Ling Li Ong; ibis-users@eda.org<mailto:ibis-users@eda.org> Cc: Siong Hee Lim Subject: RE: Role of C_comp Ling Li, It seems that your conclusion from reading Todd Westerhoff's email in the link you provided is not quite correct. Todd seems to say (correctly) that the output waveform of a driver will not change when C_comp is changed in the IBIS [Model]. You should only see differences in the waveforms when a reflection hits the driver and that reflection bounces back off of the driver. This secondary reflection from the driver should depend on the C_comp value. Similarly, if an I/O buffer model is in the receive mode (i.e. input state), you should see different waveforms when you change the C_comp value. As far as I can tell from my days when I worked at Intel and used HSPICE in my work, HSPICE does what I described above correctly. Now that I work for Mentor, I can also tell you that the results of HyperLynx are correct the same way. I am actually surprised to hear that you see different results. Are you sure your test case is designed well to show and observe these effects correctly? By the way, the latest HyperLynx version is now 9.0 (not 8.2.1). I hope this helps answering your question. Thanks, Arpad ======================================================================= From: owner-ibis-users@eda.org<mailto:owner-ibis-users@eda.org> [mailto:owner-ibis-users@eda.org] On Behalf Of Ling Li Ong Sent: Wednesday, September 04, 2013 12:47 AM To: ibis-users@eda.org<mailto:ibis-users@eda.org> Cc: Siong Hee Lim Subject: [IBIS-Users] Role of C_comp Hi, I saw some discussions on c_comp issue at user archive at link: http://www.eda.org/ibis/users_archive/0487.html I am confused by the c_comp whether it is double-counted and the different result obtained when using different tools. According to the comment in the link above, varying the c_comp may see the changes in rise/fall curve. This is definitely true when using the HSPICE simulator. But, if you using the latest Hyperlynx version 8.2.1, changing the c_comp will not reflect the changes in rise/fall curve. Can you please advise which tools are showing the correct response on c_comp when sweeping at different value? Thanks. Regards, Ling Li ________________________________ Confidentiality Notice. This message may contain information that is confidential or otherwise protected from disclosure. If you are not the intended recipient, you are hereby notified that any use, disclosure, dissemination, distribution, or copying of this message, or any attachments, is strictly prohibited. If you have received this message in error, please advise the sender by reply e-mail, and delete the message and any attachments. Thank you. -- This message has been scanned for viruses and dangerous content by MailScanner<http://www.mailscanner.info/>, and is believed to be clean. ________________________________ Confidentiality Notice. This message may contain information that is confidential or otherwise protected from disclosure. If you are not the intended recipient, you are hereby notified that any use, disclosure, dissemination, distribution, or copying of this message, or any attachments, is strictly prohibited. If you have received this message in error, please advise the sender by reply e-mail, and delete the message and any attachments. Thank you. -- 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 mikelabonte@eda-stds.org |or ibis-request@eda-stds.org | |IBIS reflector archives exist under: | | http://www.eda-stds.org/ibis/email_archive/ Recent | http://www.eda-stds.org/ibis/users_archive/ Recent | http://www.eda-stds.org/ibis/email/ E-mail since 1993Received on Wed Sep 4 20:48:49 2013
This archive was generated by hypermail 2.1.8 : Wed Sep 04 2013 - 20:49:30 PDT