How to unseal BQ20z75?

Pls see attached documentation, pg 17, section 8.3

4628.Quick-Start Guide for bq20zxx Family Gas Gauges (slua421a).pdf

thanks

Onyx

Thanks. I tried to follow the procedure.When I tried to block read 0x60, a window pops out stating:

SMB Read Block Error, Error code: SMB terminated: VB_T2H_UNKNOWN

But the chip can communicate with bqEVSW to get all the readings. SMbus seems working, what can be the issue here?

Thanks for your help.

You cant read if the device is still sealed. You need to unseal and then enter the code to have full access to the device (check same document I sent you for the full access code). Once you do this the SS and FAS bit will get cleared and then you can clear the permanent failure.

thanks

Onyx

I tried with the unseal, full access, and PF clear command, still doesn't clear the PF registers. Is this the right sequence?

Thanks

I have followed all the steps with default codes, so is it possible that a sealed pack can't be unsealed?

Yes it is possible, If the pack makers changed the default codes.