bin to avi conversion can actually mean many things, considering the vast amount of various .bin file types. But when it comes to export to AVI format, it is perhaps searched by users as some kind of attempt to either convert or recover multimedia content from .bin files.
You can certainly find tools designed for this purpose, but these typically work only for a specific, particular type of .bin files. Knowing the origin of your .bin file will help you tremendously to identify the best tool suitable for this task.