PCA85073A RTC Failure

[vaibhav_waman]

We are using PCA85073 together with supercapacitor as a backup supply. During cyclic damp heat test (95% humidity and Temperature 55 Degree) and supercapacitor as a backup supply we observed failure after 12-16 Hrs that is RTC fails to continue. But during external power(%V supply using power supply) RTC works fine.

[JozefKozon]

Dear Vaibhav Waman,

please see below a reply from a quality engineer I have contacted. Please answer his question.

DESCRIPTION

We run our moisture resistance stress of the package to JEDEC conditions.

This is 85% RH, 130C for 96 hrs under bias of max operating voltage.  The part is validated as passing if it passes the datasheet specification.
I don’t know the correlation between the customer’s moisture resistance test and the JEDEC standard.

Has the RTC been visually inspected to see if there is any ingression of moisture or contamination?

With Best Regards,

Jozef