No, they aren't. Look again.
Here's FM1608 datasheet:
http://www.farnell.com/datasheets/82469.pdf
And here is FM16W08 datasheet:
http://www.cypress.com/?docID=48242
Ah, I see your confusion
EDIT: I see mine as well - it's the newer FM1608
B which is currently on the Cypress site - guess
I missed that small part number change
You have compared the data sheet for a Ramtron part with the data sheet for a slightly different Cypress part and concluded that the difference in endurance is due to the slight change in part number - but failing to spot that there is at
least one other difference between these parts.
The supply voltage on the FM1608 is 4.5 to 5.5V
The supply voltage on the FM16W08 is
2.7 to 5.5V
In fact if you look over all of the Cypress parts
http://www.cypress.com/?id=4986&addcols=¶metric=html&filter_184=32Kb+x+8#parametric you will see that they are all specified as 10
14 cycles, both the "W" and non "W" part numbers.
So in your example it was the manufacturer that made the difference between 10
12 and 10
14, however I suspect it is really process because the Ramtron data sheet is from 2007 and the Cypress one from 2014.
In fact there is a Ramtron FM16W08 which is wide supply voltage
and 10
14 cycles but the data sheet for that is quite recent as well (2012).
It's all moot anyway because Cypress acquired Ramtron last year.
So, yes, there are 32kx8 FRAMs with 10
12 endurance and 32kx8 FRAMs with 10
14 endurance, and buying the wide supply voltage FM16W08
should get you a part with the better endurance but the "W" in that part number
does not denote the endurance, it denotes the extended supply voltage tolerance.