erasing eprom

[maurof650]

Sorry, but reading the various discussions I did not understand if for example the 27C256 without inspection window can be erased electrically.

[carmageddon]

the eprom 27cxxx without window are OTP (one time programmable) and can only be programmed once, can not be deleted.
the eeprom (electrically erasable programmable read only memory) equivalent of the 27cxxx but erasable-programmable at will are the 27sfxxx

[maurof650]

I figured it out. You know the end programmers also the delete function?

[carmageddon]

yes, of course, everyone, even those prehistoric as the needhams emp20

[maurof650]

The good (and clear as ever.....thanks). Regarding the cancellation with UV (of the eprom window) I suppose that is sufficient for a normal lamp widely used for other uses; how many seconds of exposure are required for the cancellation of the rewritable eprom?

[carmageddon]

there are kits of uv lamps affixed to the little cost that should be fine, the time varies from 2 min 6-7 min

[booster]

I'm looking for the 27sf512 but not ? easy to find them in italy
in addition, it seems that we are in trade of fake chips
I am attaching the link with instructions on how to recognize them http://support.moates.net/fake-27sf512-chips/
I hope it can be useful

[LL205gti]

I had already seen this link. ? well let it be known to those who never knew him in this community.
it seems to me that many sellers are a bit too hasty to sell one thing for another; perhaps they think that there is no difference: I recently ? did you purchase from germany of the 27c512 that according to the description were TexasInstruments (supported by my programmer); when I arrived home, I found that instead they were of the ST and who, therefore, were not supported by my programmer. what a nice surprise.