Other Parts Discussed in Thread: BQSTUDIO
Hi
I would like to clarify the maximum pack capacity supported by the BQ40Z50-R2.
The TI web page states 29000mAh. (https://www.ti.com/product/BQ40Z50?keyMatch=BQ40Z50&tisearch=Search-EN-everything&usecase=GPN)
This forum post states 65535mAh. Not sure where this value comes from. (https://e2e.ti.com/support/power-management/f/196/p/897509/3318457?tisearch=e2e-sitesearch&keymatch=bq40z50%2520design%2520capacity#3318457)
bqStudio allows a maximum design capacity value of 32767mAh.
My problem is this,
If I want a 32000mAh, or even a 29000mAh as per TI, and my pack is 4S10P made up of 4.2V 3200mAh cells with a nominal voltage of say 3.6V.
Based on this post (https://e2e.ti.com/support/power-management/f/196/t/627161?BQ28Z610-How-to-set-the-Design-Capacity-cWh-) (assuming it is correct)
the design capacity in cWh will be 3.2 * 10 * 3.6 * 4 * 100 = 46080 (please confirm)
bqStudio has a maximum value of 32767 for design capacity in cWh which means that 46080 won't fit.
if both design capacity values, mAh and cWh, are required for correct operation of this part then the real design capacity value will be less than 29000.
The question is do I need both values for this part to operate correctly?
In SLUU264A, the technical reference manual for the bq40z50-R2, section 2.3.1 they talk about Load Mode and Load Select.
Load Mode = 0 uses mAh and Load Mode = 1 uses cWh
The default appears to be Load Mode = 0 which uses mAh.
Is design capacity in cWh used for anything else? If I simply omit this value with the device still function?
I am new to these devices so if I've got it wrong please correct me.
Thanks
Andre
