Back in December 2021, LTspice changed how its
UniversalOpamps worked. They created new symbols for each "level", and each with its own corresponding
.lib file that is referenced. The problem is that they no longer include the
UniversalOpamps2.sub file anymore with any new LTspice installation. This breaks any subcircuit which relies on this file being present. I knew this broke several user-created models, but it sounds like Analog Devices' own
ADN8834.sub references the same deprecated
UniversalOpamps2.sub. This looks to be an error on their part, and I don't know how many other of their proprietary models have the same issue. Unfortunately, we can't simply go into
ADN8834.sub and tweak it to use one of the new
UniversalOpampX models instead because it is a proprietary encrypted
.sub file. Therefore, I would email "[email protected]" to inform them of the issue so they can fix it in a future release.
In the meantime, I would suggest downloading and installing LTspiceIV which can be found on the main LTspice download page under the link titled "Download for Windows XP (End of Support)". After installation, you can navigate to (assuming C: drive)
C:\Program Files (x86)\LTC\LTspiceIV\lib\sub and find
UniversalOpamps2.sub. Copy this file to
C:\Users\YOUR_USER_NAME\Documents\LTspiceXVII\lib\sub and launch LTspiceXVII. Try running the ADN8834 simulation again and it should work now. You can also uninstall LTspiceIV after you successfully copied the
UniversalOpamps2.sub file over. One thing to note is that your file associations will be messed up by doing all this, so you can launch the LTspiceXVII installer again (same download page as above, click "Download for Windows 7, 8, and 10") and it will give you the option to overwrite your existing installation. This will also repair the file associations, but you should do a
[MenuBar->Tools->Sync Release] within LTspiceXVII so you can bring everything back up to date.