Has anyone here has trouble with excessive battery leakage in backup mode?
I have learned several things recently that I believe needs to be shared here in the forum. 1) The voltage divider on SHDN suggested in the Atmel doc 11299 is completely useless in that it drains the battery in about two weeks. 2) Pulling nPBSTAT high to VDDBU as shown in the Xplained schematics is also a bad idea in that it drains the battery.
Even after undoing the things listed above, I still have about 30uA that I can not account for. My expectation was that the A5 only sips about 1.4uA in backup mode. Is this completely bogus? Is there a secret errata in an underground vault that I must seek out?