K64 IC numbering

[4Rawi]

Hi,

We have ordered some MK64FN1M0VLL12 from Aliexpress, long story short we could not get it anywhere else, we are testing the ICs and came across a diffeent numbering on the ICs after MK64FN1M0VLL12 1N83J. As an example 

MK64FN1M0VLL12

1N83J

QCTCZ1544U

Please advice if the numbers is valid or is it faked.

My question is what is those numbers indicating for? is there any information that could be extracted from those numbers?

Thank you in advance!

Regards,

Mohammed Alrawi

[vicentegomez]

 the 

MK64FN1M0VLL12 is the part number

1N83J mask set

QCTCZ1544U date code, with the manufacturing plant internal codification and year and week.

Regards

Vicente G.

[4Rawi]

Hi Vicente!

To be sure that it is that 1544 means 2015 week 44? as bobpaddock mentioned.

Regards,

[bobpaddock]

The 1N83J is the mask set.  Compare any Errata's to this mask set vs your existing mask set.
The difference can imply an age of which is newer.

https://www.nxp.com/docs/en/errata/Kinetis_K_1N83J.pdf

The other number is probably a fab/lot/date code that NXP considers "proprietary", which never made any sense to me.  1544 may mean 2015 week 44.

[4Rawi]

Hi and thank you bobpaddock!

[vicentegomez]

yes 2015 week 44