BQ77908A: Schematic Review

CHO SR

Genius 3415 points

Part Number: BQ77908A
Other Parts Discussed in Thread: BQ77915, BQ77307

Tool/software:

Hi TI Team,

The customer has completed the schematic.

Please review the schematic.

3P8S / 4P8S Battery Configuration.

UPS_Protection Circuit.pdf

3 months ago

0 Luis H. S. 3 months ago

TI__Mastermind 36500 points

Hello Cho,

I started to look at the schematic, but will have a reply by Monday .

Best Regards,

Luis Hernandez Salomon

0 Luis H. S. 3 months ago in reply to Luis H. S.

TI__Mastermind 36500 points

Hello Cho,

The R53 resistor should be between the gate-source of Q5/Q7

Else, it seems that it is copying the EVM schematic. Was there any other change from the schematic?

Is there a reason this device was chosen? There are much newer protector devices available, such as the BQ77307 or the BQ77915.

Best Regards,

Luis Hernandez Salomon

0 CHO SR 3 months ago in reply to Luis H. S.

Genius 3415 points

Hi Luis,

Thank you for your support.

There are no other changes to the schematic.

We are designing 8 cells as 1 IC due to PCB space constraints.

I will recommend the product to the customer and check if it is possible to design 2 IC.

0 CHO SR 3 months ago in reply to CHO SR

Genius 3415 points

Hi Luis,

This is the revised customer's schematic.

UPS_Protection Circuit_r02_20240827.pdf

Charge, discharge Do I need to add SPK (Spark Protection Circuit) between GND and PACK +?

Please review the SPK additional schematic.

0 Luis H. S. 3 months ago in reply to CHO SR

TI__Mastermind 36500 points

Hello Cho,

Looks good!

A spark-gap will provide further robustness against ESD strikes. I recommend to add them.

Best Regards,

Luis Hernandez Salomon

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BQ77908A: Schematic Review