Hi Kai,

this curve shows the retention time for an EPROM.
It is the same curve for FLASH-memory?
In the datasheet AT89S52 is written: Operating temp. is max 125°C, that means the retention-time is less than half a year -- is this correct, this IC is not good for my purpose: Operating temperature of my unit 24 hours every day max. 85°C: ca. 2 years retention-time - no sufficiente.

And if this curve is correct I do not believe, that retention-time is statistical founded.

with regards Manfred