Anshul, You may rely on your SPICE simulator's dynamic time step algorithm to generate the points for you as necessary, but I prefer to set the simulation time step to a low number and then extract the 100/1000 best points from that. For example, depending on the edge rate of the buffer, I like to simulate at 1 ps )or even lower if the buffer is really fast) and then use IBIS Center's "Best 100/1000 points" algorithm to reduce the total number of points from several thousand to 100 or 1000. You can look at how IBIS Center picks the best points in my presentation: http://www.vhdl.org/pub/ibis/training/IBIS_class_2003.zip on pg. 29. I hope this helps. Arpad ======================================================== ________________________________ From: owner-ibis-users@server.eda.org [mailto:owner-ibis-users@server.eda.org] On Behalf Of Anshul Bansal Sent: Tuesday, November 04, 2008 10:45 AM To: ibis-users@server.eda.org Subject: Re: [IBIS-Users] Rising falling waveform timestep Hello All, Thanks to everyone for replying to my previous post on the usage of unequal timesteps for rising/falling waveform. I understand that usage of unequal timesteps is preferred in most cases. What I wanted to know now is that is there an automated method/program/scripts that exists that most people use in creation of the rising/falling waveforms with unequal timesteps? We at Cypress Semiconductor have come up with a methodology for creation of rising/falling waveforms with unequal timesteps and I was thinking of submitting a paper for the Asian IBIS Summit at Japan. Before I do so, I wanted to know what other methods do people use. Any help would be greatly appreciated. Thanks, Anshul al davis wrote: On Monday 27 October 2008, Anshul Bansal wrote: I had a question regarding the timesteps for the rising/falling waveform. Is it legal to use unequal timestep for the rising or falling waveforms? The use of unequal timestep is preferred. You should use more points where they are needed to express detail and less points in relatively flat sections. It actually makes a difference. If your data looks like steps, with groups of consecutive values that are the same, you are using too many steps. It does matter. You may not see a problem because files like that are common so simulators will drop steps to make the waveform smooth and simulateable. -- This message has been scanned for viruses and dangerous content by MailScanner <http://www.mailscanner.info/> , and is believed to be clean. -------------------------------------------------------------------- |For help or to subscribe/unsubscribe, e-mail majordomo_ f rom _eda-stds.org |with the appropriate command message(s) in the body: | | help | subscribe ibis | subscribe ibis-users | unsubscribe ibis | unsubscribe ibis-users | |or e-mail a request to ibis-request_ f rom _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 1993 -- 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 Tue Nov 4 09:10:28 2008
This archive was generated by hypermail 2.1.8 : Tue Nov 04 2008 - 09:10:54 PST