3
\$\begingroup\$

After reading some answers on SuperUser, I started thinking: Can EE/E/PROM be damaged by only reading it, with no writing at all?

I've read several datasheets for EEPROMS and products that contain them and all I've ever seen were write and erase cycles. I do know that just reading few datasheets does not make me an expert, but up until now I was convinced that you can't wear out EEPROM and relatives just by reading them.

After some searching, I couldn't find a definitive answer which would convince me that reading an EEPROM can wear it out, so I'm asking here.

\$\endgroup\$
8
\$\begingroup\$

No, they can't be damaged only by reading.

But keep in mind that a simple read by a "complex" operating system could be followed automatically by one or more write (an example of this behaviour is the change of file last access time)

\$\endgroup\$
  • \$\begingroup\$ In this case, they were talking about BIOS chip, so I don't think that it would be directly written by the OS. \$\endgroup\$ – AndrejaKo Mar 2 '11 at 16:09
  • 2
    \$\begingroup\$ In that case... the answer is definitely NO :-) The age is the only factor that can "damage" the memory, if you only read it. \$\endgroup\$ – Axeman Mar 2 '11 at 16:13
  • 2
    \$\begingroup\$ is right. However some older parts do have data retention issue, e.g. only for 10 or 20 years. \$\endgroup\$ – Brian Carlton Mar 2 '11 at 16:32
3
\$\begingroup\$

Data will slowly degrade over time (we're talking many years) due to bit rot if the contents of the flash are not periodically rewritten. The memory cells cannot hold their charge indefinitely due to infinitesimally small leakages. Given enough time, bits will decay.

Reading doesn't cause this issue, or fix this issue. You have to periodically rewrite the contents of the flash card (once a year, maybe).

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.