BQ34110: Value of RLEN (learning load)

Elder Costa17

Part Number: BQ34110

How do I determine the RLEN (learning load) resistance? I could not find much information about it in the documentation.

EDIT: I forgot to mention the battery chemistry is NiMH, 10 cells, 5000mAh nominal capacity.

over 6 years ago

0 Matt Sunna over 6 years ago

TI__Guru* 81034 points

Hi Elder,

The learning load should be sized to discharge somewhere between C/100 to C/10 for a fixed time duration so that you see a capacity reduction of 1-2%. This video is helpful in describing the End-of-Service feature: https://training.ti.com/end-service-determination-algorithm

Since you are using a NiMH battery, there will be many flash parameter settings to update since many of the default voltages are for Li-Ion. I am attaching a spreadsheet I made to help determine some settings to start with. Hopefully this will be helpful. One important thing to note for NiMH is that the charging current should be high (~C/2) in order to properly detect when charging is complete. This is one of the biggest challenges working with NiMH.

/cfs-file/__key/communityserver-discussions-components-files/196/1856.bq34110_5F00_dataflash_5F00_notes_5F00_rev03_5F00_20181002.xlsx

Best regards,

Matt

0 Elder Costa17 over 6 years ago in reply to Matt Sunna

Expert 2825 points

Hello, Matt.

That is helpful. Thank you very much.

Elder.

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BQ34110: Value of RLEN (learning load)