What hardware fix would resolve no usb connection from an iPhone that won’t boot? I was downloading apps, and also was doing other stuff, on my iPhone when the screen suddenly went blank. I couldn't turn it on after that.

When I plugged it into a power source, it showed an 'infinite loop' of the Apple logo until I unplugged it. 

I've tried to do a restore but iTunes doesn't recognized the iPhone.  I've tried putting it into DFU mode but nothing was displayed on the screen.

Are there any other ways to fix this?  If not, should I considering replacing some parts (like either the battery or the charging port)?
You should try to replace the battery possibly. Otherwise take it to the official Apple Store &amp; ask them what to do. If you want to do every possible solution non-money wise. Clean out the power port, Use an official iPhone charger to charge it &amp; try a hard reset/restart. If none of those work yeah take it to an Apple store and they can take a look at it and tell you what to do and whats wrong.