[SOLVED] [Cadence Virtuoso Hspice simulator] set equal time step in transient simulation

How do I set equal time step in Cadence Virtuoso's ADE transient simulation, when using Hspice as the simulator? I know that the Spectre simulator has the "strobeperiod" option, but the Hspice simulator doesn't (ref: https://www.edaboard.com/threads/125944/). I can't use Spectre, because I don't have the model libraries for Spectre for the particular pdk I'm using. Thanks!

etmsni said:

but the Hspice simulator doesn't (ref: https://www.edaboard.com/threads/125944/).

Click to expand...

Wrong.
Set ".option interp".

This can work as same ability of "strobeperiod" in Cadence Spectre.i

Where can I find the ".option interp" in ADE? The first picture below is the transient analysis setting, and the 2nd picture is the option setting for transient analysis. I don't see the ".option interp"? Thank you!

ADE>Simulator>Analog Option

BTW, why do you make "UIC" enable ?
Can you understand meaning of "UIC" ?

I'm using Virtuoso version IC6.17-64b.500.5. When i go to ADE>Simulator (1st picture), I don't see analog options.


However, if I go ADE>Simulation>Analog Options, I see "Hspice Time Step Options" and "All Hspice Options" (2nd and 3rd picture).



Do I click on the "Interp" in "All Hspice Options", or do I need to change something in "Hspice Time Step Options"? (I'm not sure what any of the parameters shown on Hspice Time Step Options mean.)

Thanks for pointing out the "UIC". I don't really understand the meaning of it. Is it possible to explain what it means?

Thank you again Pancho_hideboo for your help!!! I'm really grateful for it.

etmsni said:

Do I click on the "Interp" in "All Hspice Options"

Click to expand...

Yes.

etmsni said:

or do I need to change something in "Hspice Time Step Options"?

Click to expand...

Set "tstep".
Can you understand meaning of "tstep" and "delmax" ?

Read document of HSPICE.

etmsni said:

Thanks for pointing out the "UIC".
I don't really understand the meaning of it.

Click to expand...

It is same as "skipdc=yes" in Cadence Spectre.

1. In the "Hspice Time Step Options" and "All Hspice Options", I don't see the "tstep" (picture 1 & 2) and "delmax" (picture 2 and 3) options.



I'm guessing I'm missing something obvious, but could you please point out what I'm not doing right?

2. I looked at the manual
(https://cseweb.ucsd.edu/classes/wi10/cse241a/assign/hspice_sa.pdf) and a previous post you wrote (https://www.designers-guide.org/Forum/YaBB.pl?action=print;num=1237627988). My understanding is that "tstep" is the time step, and "delmax" is the maximum time step. I'm confused about why there can be a maximum time step? (Sorry if I'm asking another obvious question here. I've been trying to learn how to use eda tools and circuit design on my own, and may be missing fundamental understanding.) I thought that time step is a fixed number.

3. (side question) Is there any advice to build up common sense to using Virtuoso?

Thank you!!!

etmsni said:

1. In the "Hspice Time Step Options" and "All Hspice Options",
I don't see the "tstep" (picture 1 & 2) and "delmax" (picture 2 and 3) options.

Click to expand...

You set both tstep and delmax as "0.0001n" in the following.
https://www.edaboard.com/attachment.php?attachmentid=140439&d=1502377365

Surely see Netlist.
tstep is not effective unless you set ".option interp".

Thank you so much Pancho_hideboo!!! You are a lifesaver!!! I am so grateful for your help. If there was a "King of IC Design" title, I think it should go to you.