BQ79616-Q1: Increasing capacity by parallel connection

Furkan Fehmi Sefiloglu

Part Number: BQ79616-Q1
Other Parts Discussed in Thread: BQ79616

Hi Team,

Can you please advise with following request:

1- An IC that can be added back to back when Bq79616 is used in series; We want to increase the battery capacity by parallelizing. We will use the bq79616 COML communication link for the procedure. Does the IC have any limitations for parallel communication when more than one IC (ranging from 10-30) is connected via a parallel COML link?

2- When we want to reach high voltages with serial connection, we want to use ring topology to make the communication more robust. This topology still uses the "bq79600- communication extender" IC of TI. Is there a more cost-effective solution that we can use with ring topology?

Thanks in advance

Best Regards

Furkan Sefiloglu

over 3 years ago

0 Taylor Vogt over 3 years ago

TI__Genius 17370 points

Hi Furkan,

1) Can they explain if they just mean adding cells in parallel or how is the COML comm port in parallel? Can they provide a block diagram to explain what they want to do? Adding parallel cells is okay from the device perspective.

2) More cost-effective than what solution? Using the 600 device? They could use a 616 as the base device but this is not typically recommended for isolating from HV packs.

Regards,

Taylor

0 Savas Sahin over 3 years ago in reply to Taylor Vogt

Prodigy 190 points

Hello Taylor,

I attached a block diagram of 2 cases, can you confirm that 2 cases have no limitations in communication perspective? or what are the limitations?

Thank you,

Savasbq79656_questions.pdf

0 Taylor Vogt over 3 years ago in reply to Savas Sahin

TI__Genius 17370 points

Hi Savas,

Case 2 is recommended. In case 1, we would recommend multi drop configuration instead where you have a separate MCU/UART interface for each 656 device. This is because if you parallel COML, there will likely be data collisions that the device is not designed for.

Regards,

Taylor

0 Savas Sahin over 3 years ago in reply to Taylor Vogt

Prodigy 190 points

Hi Taylor,

Do we need to give ID to the cell monitor devices everytime device powered up, or reset occured?(if Comm. way does not change)

If not, in case 1 if somehow device ID handling can be done properly, is it still impossible to handle paralel devices since they only respond to the commands with their IDs?

Thank you very much,

All the bests

Savas

0 Taylor Vogt over 3 years ago in reply to Savas Sahin

TI__Genius 17370 points

Savas,

Yes after wakeup/reset, the typical autoaddress routine is required to initiate comms to the stack. However, if you only go to sleep mode or burn address to OTP then you maintain the address. In theory I guess if you burn OTP address you may be able to do case 1 but we do not recommend or have tested this to ensure it works without issues.

Regards,

Taylor

0 Savas Sahin over 3 years ago in reply to Taylor Vogt

Prodigy 190 points

Taylor,

This is very clear now.

Thank you very much

All the bests

Savas

0 Taylor Vogt over 3 years ago in reply to Savas Sahin

TI__Genius 17370 points

Savas,

Please kindly click this resolved my issue button so we can close the thread!

Thanks,

Taylor

0 Savas Sahin over 3 years ago in reply to Taylor Vogt

Prodigy 190 points

Dear Taylor,

Another question raised.

Could you please tell me BQ79616's can be used in paralel operation by connecting same way in the diagram?

Thank you,

All the bests,

Savasbq79656_paralel2.pdf

0 Taylor Vogt over 3 years ago in reply to Savas Sahin

TI__Genius 17370 points

Savas,

No, I do not understand why you would want to do this. You cannot connect COMH to COMH of next device, you must connect in a string COMH to COML..all along that is the correct way to use this device.

Regards,

Taylor

0 Savas Sahin over 3 years ago in reply to Taylor Vogt

Prodigy 190 points

Thank you Taylor and Furkan for the support,

Furkan should click to resolved my issue button.

All the bests,

Savas

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BQ79616-Q1: Increasing capacity by parallel connection