PSpice/LTSpice compatability

[alec_t]

Couldn't find a LTSpice model for INA128 instrumentation amp but did find a PSpice model. Can LTSpice work accurately with PSpice models, or does it just ignore any bits it doesn't understand (which would result in inaccurate modelling, but maybe not let the user know that) ?

 

[ericgibbs]

hi alec,
I have tried some Spice to LTS conversion in the past, but I found I got so many errors it would not run.
Did try editing out some errors , but no luck.

What I tend to do now is to create a hierarchical model of the OPA using the diagram and component values from the datasheet.
If you choose a Linear devices OPA having a similar specification to create the model, the performance will closely match the original IA.

For the INA128 , look at the LT1167 listed in LTspice OPA options, its a close fit for the INA128.

If you need a hand with the model just ask.
E.

 

[alec_t]

Thanks for the offer, Eric. Think I'll just use the LT1167 model as is.

 

[Roff]

The Pspice INA128 model works for me. I ran AC and transient sims on it with good results.

 

[ericgibbs]

The Pspice INA128 model works for me. I ran AC and transient sims on it with good results.

hi Roff,
Many thanks, it works for me too.

E.

 

[alec_t]

Thanks guys. Nice to know it works. As per post 1 I just wonder if it works completely correctly

 

[Roff]

Thanks guys. Nice to know it works. As per post 1 I just wonder if it works completely correctly

I thought about that too. Looking at the subcircuit, I don't see any elements or syntax that LTspice doesn't understand.
The Error Log doesn't have any fatal errors (they would have been reported on screen).
I have imported a lot of Pspice models. I may have run into a few that wouldn't work.