topic Re: Eagle SPICE Simulation Models not Loading Correctly in EAGLE Forum

Eagle SPICE Simulation Models not Loading Correctly

Anonymous — Fri, 11 Sep 2020 22:05:46 GMT

Hi there, I've spent a lot of effort attempting to learn how to simulate using SPICE within Eagle. I have read the Eagle Academy blog posts and watched the autodesk videos on youtube. I am trying to use diode models provided by a handful of manufacturers that I have found on the internet, but I cant seem to get any of them to work. I get the following errors every time I try and run a simulation. I'm determined to understand how SPICE works within eagle but am finding it very difficult. I would greatly appreciate any help I can get.

Thanks!

Faith.

Re: Eagle SPICE Simulation Models not Loading Correctly

Anonymous — Sat, 12 Sep 2020 04:22:40 GMT

I think I am getting somewhere. I read on another post on the forum that in order to map a non intrinsic diode model I need to map it as a subcircuit. I noticed that in the manual it shows the following at the end of the model text in a subcircuit example:

.SUBCKT <model_name> N1 <N2; N3 ...>

.ENDS <model_name

Presumably, the .SUBCKT and .ENDS lines are to tell EAGLE that this is the end of the subcircuit model description, but what does "N1 <N2; N3 ...>" mean? Just for kicks I tried adding it to the end of the model description,(or is it the model definition?) but it came back with the error "The # of pins on the part(2) must match the # of pins(4) in the model definition. I read through the model text and couldn't find any abbreviations that appear to reference the number of pins in the model. I checked in the map pins tab but there is nothing listed there except for "D1" which is the part label. I'm stumped at this point but will continue reading the manual and messing around in eagle. Any help would be very appreciated.

Thanks!

Faith.

Re: Eagle SPICE Simulation Models not Loading Correctly

demariano95 — Thu, 17 Sep 2020 13:43:35 GMT

I am having the exact same problem as you. Was trying to simulate a circuit with a BZX84C5V1 zener diode. I noticed it is present in the built-in library but there is no .mdl associated with it. So I searched online and found a SPICE model that apparently is fit for the zener diode, but when I try to import it into Eagle I only get errors and the simulation never works.

I had that mismatch in the pin number error too, but then I messed with the .mdl code and got through it. Ultimately I am getting the following error message:

I am also determined to learn to work with Eagle and to make this work, but would really appreciate any help I can get.

Re: Eagle SPICE Simulation Models not Loading Correctly

jorge_garcia — Thu, 17 Sep 2020 19:49:47 GMT

Hi @demariano95,

I hope you're doing well. Since the model has a subcircuit you have to go to the previous dialog and set the type of the component to be X. Once you do that then it will allow you assign the model.

Let me know if there's anything else I can do for you.

Best Regards,

Re: Eagle SPICE Simulation Models not Loading Correctly

demariano95 — Thu, 17 Sep 2020 19:55:36 GMT

Thank you for your answer, and as a matter of fact there is something else you could probably help me with.

I have already tried changing the type of the model to X: Subcircuit. And indeed it allowed me to save the model.

But when I go to try and simulate the circuit, an error pops up with the message "Missing SUBCKT: bzx84c5v1", which is the model I had just saved in the add model dialog.

Thanks in advance!

Re: Eagle SPICE Simulation Models not Loading Correctly

demariano95 — Thu, 17 Sep 2020 19:57:28 GMT

In my previous post I meant to say something along the lines of "how do I fix this error?" but forgot lol

Re: Eagle SPICE Simulation Models not Loading Correctly

Anonymous — Sun, 20 Sep 2020 16:08:32 GMT

Hi Demariano95, I came across the same problem myself while tinkering with a zener model. It turns out that the problem was in the model name of the diode. If the Model name that you provide in the "Load Model" window does not match the model name in the .SUBCKT line within the model text, then the simulator won't be able to find it when running the simulation. I'll include an example below.

Cheers!

Faith.