TPS65950A recommended backup accumulator

Sergey Avdjushin

Intellectual 285 points

Hello!

I use TPS65950A with input supply voltage of 3.3V.
I do not get to choose the correct backup battery.

Can I use a lithium battery with a voltage of more than 3.3V?
Usually they have until the voltage reaches 4.2 V.

(I do not understand whether the voltage can exceed the power supply voltage.)

I could not choose a rechargeable battery with the recommended voltage from 1.8 to 3 V.

Serg.

over 9 years ago

0 AlainC over 9 years ago

TI__Intellectual 1915 points

Hi, I see two problems here:

-BACKUP maximum operating voltage is 3.3V per data manual

-VBAT won't be able to charge such battery since it is a 4V

So overall it would be preferable to change it for a 1.8V to 3V battery.

Best regards, Alain.

0 Sergey Avdjushin over 9 years ago in reply to AlainC

Intellectual 285 points

Another point. BKBAT must be connected to ground if not used. Can I leave this PIN not connected, if I do not know whether the battery is installed or not?

0 AlainC over 9 years ago in reply to Sergey Avdjushin

TI__Intellectual 1915 points

Hi, a floating level is not recommended as it could falsely report a high level indicating that a backup battery is plugged-in while there is none. At least a cap to ground in parallel with the backup battery would prevent this issue whenever the battery is not present.

Best regards, Alain.

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TPS65950A recommended backup accumulator