Hi,
I'm planning to use the "backup battery system" provided on MSP430F5635 to maintain the RTC state when my main power is off. The document is pretty straight forward regarding such capabilities.
My question lies in using such system with a non-rechargeable coin cell battery such CR1220 or CR2032. I know the system charger can be turned off, but what reverse current can I expect to be applied on my battery?
I don't have any numbers, but some research I did implies that any reverse current on such batteries is harmful and can result in catastrophic results. Some documents says 1uA is fine, but others says that any current resulting in 3% charge of total capacity in any given time can have bad results.
What is TI recommendation on such matter? Can I safely connect any coin cell on Vbat pin and expect to work reliably?