It has AD8420.cir but not sure how to install this into LTSpice.
When you going to release LTSpice version of AD8420.
AD8420 Spice Model will be uploaded in LTSpice in the near future but there is no definite time table as of this moment.
For now, attach here is a symbol file you can use.
You can put it on your PC "C:\Users\<username>\Documents\LTspiceXVII\lib\sym" directory.
Regarding the AD8420 cir file, put it on your "C:\Users\<username>\Documents\LTspiceXVII\lib\sub" directory.
By the way, you could try to import spice models in LTSpice by following the steps on this link
Solutions - LTspice: Simple Steps to Import Third-Party Models.
Hope this helps.
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