Data retention - lifetime prediction of modern calculators

[Steve Simpkin]

(07-12-2018 08:57 AM)sasa Wrote:  While very old calculators may still works fine after 45+ years, nowadays calculators (including any electronic today) may have a very short life. According to the most problematic lifetime component (capacitors), the lifetime of general electronic are usually the same as a warranty not exceed 3 or 5 years.

Aside of that, the datasheet of nowadays MCUs used flash memory typically state retention times of 20 years at 85 °C and 100 years at 25 °C (in this case former ATMEL MCUs, in specific controlled environment). SRAM have much shorter lifetime (up to 5 years, IIRC). And as well humidity may influence moderately. Of course, these figures are given for ideal conditions tested - I hope there is many EE here which may elaborate with more precise information.

Modern surface mount electrolytic capacitors usually only have a short lifespan only if they are constantly exposed to high temperatures. At normal room temperatures, they will typically last for decades (assuming they are not of poor quality or defective).

The same is true of Flash memory. If not constantly exposed to high temperatures, they will retain their data for decades.

I have never heard of endurance issues with SRAM.

One potential item to be concerned with is the use of lead-free solder in modern (since 2006) electronics. There have been reported cases where "whiskers" have formed between soldered component leads that have resulted in device failures. I believe the potential for this problem has been largely mitigated through the use of additives to the tin used in the component soldering process.
More information on this subject:
https://www.maximintegrated.com/en/app-n...vp/id/5250
https://nepp.nasa.gov/WHISKER/background/