how much time is required to erase data from an EEPROM ?

[info_req]

eeprom erasing time???

how much time is required to erase data from an EEPROM(27c512) with Ultraviolaet eraser.

Thanks.

 

[echo47]

eeprom erasing time???

That depends on the intensity of your UV lamp.
The AMD Am27C512 data sheet says it requires a total dosage of 15 watt seconds per square centimeter at 2537 angstroms:
https://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/08140.pdf

I once used a small lamp that required about an hour. Once, I also tried a carbon arc lamp that took only a few seconds (pretty scary). Most EPROM erasers are somewhere in between.

 

[nikhilele]

eeprom erasing time???

if i put same eeprom in Sunlight what will happen

 

[echo47]

eeprom erasing time???

Bright direct sunlight can gradually erase an EPROM (that's mentioned in the AMD data sheet), but it could take weeks depending on your weather and latitude.

Back in the days when I used EPROMs, I would test a new unknown UV lamp by checking the EPROM periodically to see when it appeared blank, and then I'd give it an additional dose of twice that time, just to be sure. For example, if it appeared blank after 15 minutes, I'd give it an additional 30 minutes for a total of 45 minutes.