op amp power on/off

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ronv

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I noticed this problem with a spice simulation while looking at power sequencing.

When the supply voltage falls there is a huge current spike in the op amp. It only seems to happen with models I have downloaded and not with the Spice supplied op amps. I'm guessing it has something to do with how I made the models, but I don't know.
Anyone seen the same problem? Or. do you have it with your downloaded op amps?
Thanks.

PS ASC attached.
 

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hi Ron.
This what I see on my LTS , using the LM324.sub

Just a few mA, which I would expect.

Eric

EDIT:
Added my LM324.sub , change the .txt back to .sub
 

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Last edited:
Hmm. Must be the way I make the models. Did you make yours from the ideal op amp or just modify an existing op amp in the library?
 
What I have been doing is using a spice model with the same pin out and modifying it to call the 324 sub. Doing that I don't need the include statement but I fear it may introduce this problem. I guess what I was really asking is what did you use to build the symbol?
 

hi,
This is one I sourced some time ago on the web.

Rename from LM324.txt to LM324.asy

E
 

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Boy, I hate to ask you this again...

Where do you save your sub and sym files?

Do you define the path to the sub in the symbol attribute window or is that done with the include statement.
 
ronv said:
Boy, I hate to ask you this again...

Where do you save your sub and sym files?

Do you define the path to the sub in the symbol attribute window or is that done with the include statement.
Click to expand...

hi Ron,
No problem.

Look at this image for the folders.

E
 

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Thanks Eric,

I just put your subcircuit file in place of mine and it fixed it. Imagine my surprise!

So you don't use a separate sub folder for your downloaded circuits-they are just in with the regular ones? I have a folder I call new in the sub and symbol folder. Maybe that's why I have so much trouble following other peoples directions.
 
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