by pebe » Tue Sep 16, 2014 12:33 pm
You have still not provided enough information to work on.
Did the circuit develop a fault? If so, what were the symptoms? What is the make and type of the LDO? What other measurements have you made? How is the tracking voltage set? Can you give the circuit details?
Without more detail, you might just as well ask how long is a piece of string!