Erasing Eprom by using UV-Led

From: Bob Shannon <bshannon_at_tiac.net>
Date: Sat Oct 11 09:25:46 2003

Hello Adrian,

I used an LED I got at a Ham-fest, so I'm unsure of its exact model
number. I beleive its made by Cree however, and
it is a 'true' UV led with very little visible emission.

I never measured the minimum time needed to erase the EPROM, I'd left it
running overnight, so it was erased in
about 12 hours, perhaps much less is needed.

The LED was about 3 cm from the EPROM window.

I have not tested other EPROM devices, but I easily can. I'll try a
test with a 87C52 over the weekend.

If you want a combined programmer and eraser, why not use FLASH chips
rather than EPROM?

Adrian Haunstetter wrote:

>Hello Mr. Shannon,
>
>in the topic "A way to erase OTP components?" I read that you succeeded to erase windowed 27C512 using a UV-Led.
>Because I'm about to build a combined Programmer/Eraser, where erasing shall be done with UV-Led, I like to ask you about your experiences.
>What type of Led do you use?
>How long do you need to erase?
>What was the distance between Led and Chip?
>Did you made Test with other devices?
>I hope you take a little bit of your time to answer me.
>
>With best regards
>
>Adrian Haunstetter
>
Received on Sat Oct 11 2003 - 09:25:46 BST