Why is the flash package marking different from the ordering part number (OPN) I ordered?
Flash memory dies are becoming smaller due to continuously shrinking process technology, which leads to tiny package sizes. The small package surface does not allow for readable characters if all OPN characters are used, so some characters are not printed to make the remaining characters large enough to be readable.
Refer to the corresponding ‘Ordering Part Number’ section from the datasheet to see all the valid part number combinations including the package marking.
For example, the ordering part number (OPN) for the S25FL-L is defined as follows:
The valid combinations for the standard part are listed below:
As you can see from the above tables, package marking omits the second character of the speed option, the first and last characters from the package/temperature code, and the character code for packing type.