Hallo Lee, hallo Stephane,

The latter is not a recommended approach. I don't know if that works where Kai is from, but it is a good way to go to prison in the US.

I added a {grin} to my statement, to show, that this was ment as a joke!

Anyway, I found that availability of information in web about 'data retention time versus temperature' has drastically increased in the last year. And I found, that manufacturers probably have very different fabrication processes leading to very different specifications.

Have a look at the following links:

http://www.simtek.com/App-Notes/AppNote03.pdf
http://www.hc08.cz/attachments/sps_flash.pdf

Seems to me, that certain motorola chips are very well suited for your purpose, Stephane. By the way, I have seen many motorola chips, e.g. in 'digifant' motor controlling units.

Bye,
Kai