A developer can do diferent tasks, such as writing code, analyzing data, and contributing to the software design. 

A developer is one who is able, through programming languages, to bring ideas, requirements, solutions to reality, make decisions in complex contexts of uncertainty that solve problems and allow the tasks automation.

The developer is the one who does the "magic" of became client's request into reality.

The functional analyst proposes, performs functional tests, listens to users, negotiates, communicates, acts as an intermediary between users and developers / testers, documents to define the expected functionalities of a system.

The functional analyst collection the user's need and details it in a clear and complete way to ensure the delivery of a correct and quality product.

I like to say that the functional analyst is the intermediary between the client and the developer and that he somehow translates what one wants to communicate to the other.