I happened across this nice article last week when looking for some information on 5GHz channels. It should clear up any misunderstandings you may have about channel allocations and bandwidth too. It uses Mikrotik channel nomenclature (eg Ceee). Don't rely on Mikrotik's 'auto' channel selection, you'll end up in tears.

http://goughlui.com/2018/06/04/note-cho ... 1ac-in-au/

There is also tear down of some Mikrotik devices.

http://goughlui.com/2018/08/05/teardown ... terboards/