BQ40Z80: GPCRA0 calculator using scaled current or actual current?

Tym Zhu

Part Number: BQ40Z80
Other Parts Discussed in Thread: GPCRA0,

Hi, I’m trying to use GPCRA0 to generate gg file for bq40z80 gauge. The results have Qmax set to the actual mAh rating of the battery. With scaling factor set, I’m assuming Qmax should scale as well? What’s the correct procedure? What I will try next:

Do ChemID using the true current reading without any scaling.
Program the ChemID and then use the scaled down current for GPCRA0 tool to get the gg file.

over 3 years ago

0 Abraham Rashid over 3 years ago

TI__Expert 3030 points

Hi Tym,

Actual current value should be used.

Best Regards,

Abraham

0 Tym Zhu over 3 years ago in reply to Abraham Rashid

Prodigy 60 points

Hi Abraham,

Thanks for your reply!

I'm a bit confused. So you are suggesting that the Qmax and Ra values should not be scaled according to the scale factor?

For example I have a 4000mAh battery with Ra0 of 40mOhm, and scale factor is set to 4. Qmax reading from the battery should still be 4000 and Ra0 should still be 40?

0 Abraham Rashid over 3 years ago in reply to Tym Zhu

TI__Expert 3030 points

Hi Tym,

Scaling for current and Qmax works separately. If actual Qmax doesn't exceed the max value supported by the gauge, there is no need to scale Qmax. So if you turn on current scaling only, Qmax and Ra values shouldn't be effected.

Best Regards,

Abraham

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BQ40Z80: GPCRA0 calculator using scaled current or actual current?