Tiny Mystery Board on Logic Board

In the far right corner of the logic board there is a tiny 1"x3/4" board that when you look at new logic board is not present.

What is this board?

I guess it's the CLICK WHEEL BOARD

I know it has something to do with total operatioin of the iPod because mine was slightly out of place and the iPod would work with the hold button in the on position and would not charge the battery.

When I pressed it back into place everthing worked fine. The iPod had been dropped.

EDITED: Thank you for your reply. I didn't know I actually had to drag the picture to the text. Looking for a good picture I found this one with the CLICK WHEEL attached to the tiny board in question.

NOTE: I've discovered that if this board becomes dislodged it acts the same as a questionable LOGIC BOARD. EI: no charging, shuts down in the HOLD button ON position.