TPS65950 - Current draw on the backup battery that runs RTC

Roger Liang

I am measuring about 7 uA on the RTC battery current when the device is in the BACKUP state. I was expecting 1uA based upon my interpretation of the data sheet.
p137, Table 12-5.

My question is: what is the worst case current draw on the backup battery that runs the RTC when the unit is in BACKUP state?

over 14 years ago

0 Roger Liang over 14 years ago

TI__Expert 3510 points

Another question. P137, table 12-5 shows bits for LOJIT.

What are those 2 bits? Are they R/W?

0 Gandhar Dighe over 14 years ago

TI__Genius 15100 points

Hi Roger,

This looks higher than expected. I dont know what peripherals are ON and how you are measuring the current. I am pasting a link below for your reference. The info on the link below is from an FAE who was measuring on the customer board -

http://e2e.ti.com/support/power_management/pmu/f/43/p/67564/252920.aspx#252920

About LOJIT bits - yes, they are RW and it is better to have these set to '1'.

Hope the link above helps.

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TPS65950 - Current draw on the backup battery that runs RTC