MMPF0100 always in TBB-mode?

[mahi]

Hi Community,

we are currently using MMPF0100NPAEP in TBB mode on our custom board. For power management and monitoring of the rest of the board, we are using a Kinetis µC which currently also takes care for the MMPF0100 registers.

None of the preprogrammed variants match our requirements and due to our low quantities, preprogramming an own scheme is not really reasonable.

For production we could either use the OTP-feature to program the device in circuit or we just keep TBB mode "forever". As OTP programming would require an additional step in board bringup-procedure (at least apply VDDOTP - the Kinetis could take care of the rest), staying with TBB would require the owest effort.

Does using TBB have any influence on durability or reliability of MMPF0100?

Is there a "TBB write count limit"?

Best regards

 Martin

[mahi]

Thanks for your reply.

Currently I write the registers of MMPF0100 on every power-on (no coin cell) and it works just fine. As the PMIC and the microcontroller are powered from the same source, dropouts on this power rail would restart both, so the TBB contents would be restored.

Additionally the power supply is redundant, so dropouts are pretty unlikely.

Best regards
 Martin

[david_diaz · Accepted solution]

Hello Martin,

You can continue using TBB mode.

The TBB do not have any influence on durability or reliability of the PMIC and it does not have a “TBB write count limit”, just be aware that you would need an external coin cell battery connected on LICELL pin to maintain the TBB configuration.

VIN, or the coin cell voltage must be valid to maintain the contents of the registers. To power on with the contents of the TBBOTP registers, the following conditions must exist; VIN is valid, VDDOTP = 0.0 V, TBB_POR = 1 and there is a valid turn-on event.

I hope this information help.

Best Regards,

David