BQ77216: How to select shorted inputs in BQ77216

Andrea Colombo

Part Number: BQ77216
Other Parts Discussed in Thread: BQ76940

I have a battery pack with 8 cells. I have to design a slave board with a battery monitor like BQ769x2 and I want to add also the BQ77216. I must choose which inputs of BQ77216 I have to short to work only with 8 cells instead of 16 supported by the device. Reading the datasheet of BQ77216, in chapter 10.2, there is the following text

"When paring with the BQ769x2 or BQ76940 devices, the top cell must be used"

If I well understand, this means that I must place a cell between V16 and V15?

Do I have some other constrain in choosing the shorted inputs to work with only 8 cells?

Regards

Andrea

over 2 years ago

0 Max Verboncoeur over 2 years ago

TI__Mastermind 25605 points

Hi Andrea,

We generally recommend shorting the unused cells from the top down. In addition to requiring a cell to be present between V15 and V16 when connecting to a BQ769x2, the BQ77216 requires a cell to be present between VSS and V1 for proper operation.

You can read more about this in Section 3.2: Reducing the Cell Count of the EVM User Guide.

I hope this answers your question!

Regards,

Max Verboncoeur

0 Andrea Colombo over 2 years ago in reply to Max Verboncoeur

Prodigy 10 points

The request to connect a cell between V15 and V16 came from the characteristics of BQ769x2 or it is a general requirement even if I use a different device for cells monitor and equalization like LTC6811-1 from "analog device"?

0 Arelis Guerrero over 2 years ago in reply to Andrea Colombo

TI__Expert 5645 points

Hi Andrea,

Today is the 4th of July US Holiday, so the team is out of office. We will get back to you on July 5.

Regards,

Arelis G. Guerrero

0 Max Verboncoeur over 2 years ago in reply to Andrea Colombo

TI__Mastermind 25605 points

Hi Andrea,

That's correct! If you're not connecting to a BQ769x2 or a BQ76940 then the BQ77216 does not require a cell between V15 and V16. That is a requirement of the BQ769x2 and BQ76940 devices, not the BQ77216.

I hope this helps!

Regards,

Max Verboncoeur

Power management

Power management forum

BQ77216: How to select shorted inputs in BQ77216