BQ2982: Singe Li cell protection

Prithvi Raj Narendra1

Intellectual 610 points

Part Number: BQ2982
Other Parts Discussed in Thread: BQ25895, BQ2980

Tool/software:

Hello,

We are looking for a Li cell protection where with the following specs:

OV cut off @ 4.2V - we will perform CV charging at 4.15V

UV cut off @ 3.2V preferable, 2.8V lowest.

The closest I can find for this is with BQ2982 series, where I need to use BQ298218 (OV at 4.2V) for OV detection and BQ298009 or BQ298010 (UV of 2.9V) for UV detection. Would this be possible to use two of BQ298x series, one for OV and one for the UV? Or is there any other option available?

Regards, Prithvi

3 months ago

0 Luis H. S. 3 months ago

TI__Mastermind 38630 points

Hello Prithvi,

In theory you may be able to put them in series if done correctly.

Do you require any other type of protections?

Best Regards,

Luis Hernandez Salomon

0 Prithvi Raj Narendra1 3 months ago in reply to Luis H. S.

Intellectual 610 points

To start with OV and UV would be the main protection needed since I can use a fuse for over current in case it can't be done.

Looks like BQ2982 can do over current cut off as well. Can you please guide me on how I can use BQ2982 to meet my requirement with back to back MOSFETs?

Regards, Prithvi

0 Luis H. S. 3 months ago in reply to Prithvi Raj Narendra1

TI__Mastermind 38630 points

Hello Prithvi,

I advice you read the datasheet and look at our EVM for guidance in how to implement the BQ2982 in your system.

Best Regards,

Luis Hernandez Salomon

0 Prithvi Raj Narendra1 3 months ago in reply to Luis H. S.

Intellectual 610 points

Thanks Luis. Finally decided to use BQ298009 for UV, OCC, OCD and temp protection. For OV protection, planning to use TLV803EA42RDBZR to detect 4.2V and have the ~{RESET} pin with a pull up control the ~{CE} pin of BQ25895 series charger.

Any flaws you see with this approach? Thanks.

Luis H. S. said:
I advice you read the datasheet and look at our EVM for guidance in how to implement the BQ2982 in your system.

+1 Luis H. S. 3 months ago in reply to Prithvi Raj Narendra1

TI__Mastermind 38630 points

Hello Prithvi,

I think that could work from the BQ2980 perspective. But I am not too familiar with the charger, I would recommend to open a new thread to ask the charger team if they have any concerns.

Let me know if you have more questions!

Best Regards,

Luis Hernandez Salomon

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BQ2982: Singe Li cell protection