BQ76940: bq76940 for 13s application

Sammi Shang

Part Number: BQ76940

Dear team,

When customer change BQ76940 from 15S to 13S, they connect C8 with C9, C11 with C12 directly, so they want to cancel the UVLO setting of these two pin C9 and C12 due to the voltage turn to 0. Do you have any suggestion?

Thanks.

Best regards,

Sammi

over 5 years ago

0 WM5295 over 5 years ago

TI__Guru 54715 points

Hi Sammi,

See the BQ76940 data sheet section 11.1.1 for reducing the cell count. https://www.ti.com/document-viewer/BQ76940/datasheet/configuring-alternative-cell-counts-slusbk24812#SLUSBK24812 For 13 cells it is recommended to short VC13 to VC14 and VC8 to VC9. It may work to short cell 12, but it is not recommended.

When a cell is shorted if the converted voltage is below UVMINQUAL it will not be detected as under voltage, see the note in section 10.3.1.2.1 https://www.ti.com/document-viewer/BQ76940/datasheet/integrated-hardware-protections-slusbk24522#SLUSBK24522 and the entry in the electrical characteristics section. No UVLO for the shorted cell. If there are residual counts they are added in the battery voltage register calculation.

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BQ76940: bq76940 for 13s application