I found the following circuit symbol in an MSP430 User's Guide in the section describing the ADC:
(I made a red circle around it)
What does it represent?
I've seen varactor symbols that look similar, but they always have two parallel lines at the top of the triangle. A triangle pointing upwards can also be used to represent a power plane, but that doesn't make sense due to both it's location, the line through it, and the current source directly above it.
Is there a legend somewhere in the document that might explain it? Also, if we had an image of the entire schematic someone might be able to piece together what it might be.