BQ20zxx device could not unseal

Dear All:

When mass-production, happen Z device could not unseal.

After moved the PCBA from the cell bank, and re-connected , then can unseal.

Do you have good suggetion for above issue?

Thanks a lot!

0 Macy over 16 years ago

how about sending 0x41 to full reset the device! and then enter the unseal command.

0 M2 over 16 years ago in reply to Macy

No.

Only way must power off, then power on.

I sespect that DF was corrupted.

0 rohit devmore over 16 years ago in reply to M2

try to send following codes to manufacturer access (oo)

0x3412 and 0x7856.

see if it works.

0 Jerry Yang15781 over 15 years ago

Dear Mike,

I also found this issue on mass production line. The sympton is same.

Could you tell me what is the Z device part number(bq20z75 or bq20z95) on your mass production line?

Thanks.

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