From Friday, April 19th (11:00 PM CDT) through Saturday, April 20th (2:00 PM CDT), 2024, ni.com will undergo system upgrades that may result in temporary service interruption.

We appreciate your patience as we improve our online experience.

Multisim and Ultiboard

cancel
Showing results for 
Search instead for 
Did you mean: 

How to set a specific "time step" when I want to run a Transient Analysis

How to set a specific "time step" when I want to run a Transient Analysis. I only find "the Maximum time stemp seting", but I want to set a specific ''time step", not the maximum time step. I hope that each time step is equal. How can I do? 

0 Kudos
Message 1 of 5
(18,637 Views)

No one know?

0 Kudos
Message 2 of 5
(18,559 Views)

Hi David,

 

You cannot set fixed sampling rate in any SPICE simulators, the SPICE engine decides what steps to take base on what's happening in the circuit at that time. Your only option is to set TMAX, this tells the SPICE engine the max step it is allowed to take, but if it needs to take smaller steps it will.

 

Here is an example of a square wave. You can see there are more red dots near edge than the flat part of the signal, this means the SPICE engine decided that it needed more sampling near the edge so it takes more samples, but once it sees that the signal is not changing much it takes bigger steps to make the simulation run faster. This is the way SPICE works.

 

sampling.png

Tien P.

National Instruments
Message 3 of 5
(18,550 Views)

Thanks for your reply !

0 Kudos
Message 4 of 5
(18,540 Views)

Hi Tien,

is it still not possible to set fix "time step" in Multisim 14.0?

I do really want data with a fix sample frequency. Could you please give me some suggest?

Thank you so much!

Ying

0 Kudos
Message 5 of 5
(16,749 Views)