Did you use the Debian edition of Mint? Debian doesn’t include a lot of proprietary drivers and/or firmware blobs with its standard edition.
I can’t say that’s the case here, but it’s possible that Mint is either using Debian as a base, or at least following the Debian Free Software Guidelines.
There’s usually a nonfree firmware deb you can use, post installation. If you can complete the install and connect to the internet via the 7480’s Ethernet port, you should be able to get the wifi card working.