TPL5110-Q1: TPL5110-Q1

Hi,

I am using the TPL5110 in the timer mode as a periodic sleep/wake/done with a microcontroller and I noticed that the boards works fine but after testing the boards for a long time like more then 1 day some of the boards stops working and when I re-insert the battery the system works fine and stops after an undefined time sometimes hours or days.

I added a pull down resistor to the done signal and for now none of the boards tested stopped. I can't find any related proposition or recommendation adding a pulldown to the done signal or that it can't be left floating. so my question is : 

What is in your opinion and the explanation behind this scenario ?

Can this solution ensure the long time functioning of our product ?

Thanks