Unique Device ID on MM912J637

[igw]

Hello all,

The data sheet for the MM912J637 has a section describing the MCU Information Register (IFR).  Within this there is an 8-byte entry labelled "Unique Device ID" (see page 395 of the Rev 3.0, 1/2012 data sheet).

However there are no details on this ID elsewhere in the data sheet. Just this one mention in a table.

Is anyone able to give any more info on this 8-byte ID register?

Is it, as it suggests, a globally unique ID?  Is it preprogrammed from the Freescale factory?

Bottom line, can I trust it to uniquely identify a particular chip (and hence assembled board)?

Thanks,

Ian

[RadekS · Accepted solution]

Yes, it is really unique ID preprogrammed by Freescale factory. Cannot be changed.

Meaning of bits in this ID is Freescale internal information and cannot be provided to customers.

However this ID contains also production date,....

So, you will newer get two MM912J637 devices with the same ID.

[igw]

Thank you Radek.  That is just what I needed to know.