bq40z50-R2: Full charge capacity update during discharge and relax

uday kumar reddy

Part Number: BQ40Z50-R2

Hi,

We are using gass gauge BQ40z50-R2 for 4cell Li-ion battery pack. The full charge capacity of the gauge is continuously updating (from 300mAH to 15000mAH, where Qmax=19200mAH) while charging and discharging and relax times,accordingly Remaining capacity also updating. I observed update of the FCC when reading SREC file from the device also.

I have completed only one learning cycle (FYI).

1. Please let us know does this FCC update is as per the fuel gauge design... if not please let me know what are the settings I need to take care to lock the FCC at some particular value.

2. and Please help me in understanding AFE protection operation (if any document available please share with me)

Thank you,

over 6 years ago

0 Onyx Ahiakwo over 6 years ago

TI__Guru* 76230 points

1. When you say you completed a learning, cylce, do you have update status as 06 or 0E. if it isn't either of these, it means your learning never completed successfully. You need to correctly identify your chem id and program it on the gauge before carrying out the learning cycle. Pls follow the app note below to carry out a successful learning cycle.
www.ti.com/.../slua777
2. For understanding of the AFE, pls check the technical reference manual of the device in the link below
www.ti.com/.../sluubk0

thanks
Onyx

0 uday kumar reddy over 6 years ago in reply to Onyx Ahiakwo

Intellectual 520 points

Hi Onyx,
Thank you for your response... the update status after learning cycle was 0E.
you mean to say that if the learning cycle is successful the FCC value update will be within the range? and why the FCC value is updating by reading the SREC file from the device?

I will go through the document for further learning cycle. Thank you for sharing the information.

Thanks& Regards,
Uday kumar

0 Onyx Ahiakwo over 6 years ago in reply to uday kumar reddy

TI__Guru* 76230 points

The process of Extracting an srec causes a reset command to be sent to the gauge. When a reset command is set, the new Rem cap simulation occurs and that causes FCC to update.
thanks
Onyx

0 uday kumar reddy over 6 years ago in reply to Onyx Ahiakwo

Intellectual 520 points

Hi Onyx,

thank you for your information.

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bq40z50-R2: Full charge capacity update during discharge and relax