Now, go to eBay, seek for "FM1608", and all the parts you will get will be Ramtron ones.
Then, do the same with "FM16W08", and you will again get some Ramtron devices.
Then, on the Cypress page, look for "FM1608", and you will get nothing. 16W08 is there.
So, in practice, buying FM1608 from eBay, you cannot know what exactly you are buying - a device with 10E14 or a device with 10E12 cycles. Buying 16W08 you are sure it is 10E14.
I'll agree with you as far as "from eBay, you cannot know what exactly you are buying"
P.S: I would like to see that datasheet for 1608 with 10E14 rating. I cannot find it anywhere. Can you please give a link or upload it here?
Now I look it's a FM1608
B http://www.cypress.com/?docID=48234, Cypress don't currently list an FM1608, as you say.
You are correct that the FM1608 is 10
12 and you are correct that buying the FM16W08 will be a higher endurance part, just that the "W" does not mean higher endurance per-se.
In fact the plain FM1608 is obsolete and the FM1608B is supposed to be the replacement - so that's the normal supply range but 10E
14 endurance part - there are some notes about the differences here
http://www.cypress.com/?docID=47983, note that the new part is not better across the board - it has higher standby current requirements and under some conditions has lower data retention.
The other reason that you are correct
in practice is that I can't see anywhere with an FM1608B in stock, whereas the FM16W08 does appear to be available.
Sorry - it's splitting hairs and for that I apologize -
but you know how it is (actually that's a bit unfair as you weren't really wrong)