eprom eraser question

[cp]

Just wondering...  Is it possible  to "overcook"  eproms  in a  UV  eraser ?    My eraser has an  electro / mechanical  timer.   I had some  8 meg  eproms in it.  Put the timer on...  and  it  somehow  got stuck and the  UV  was on for  24 hrs.  !

[brichter]

I've never seen it happen, but 24 hours is a long time...

[Ron (r273)]

Here is some info I found on the net.

Every time an EPROM is programmed and erased it wears out a little. Erasing cycles will slow down access times, but this is usually of no consequence unless you erase them an extreme number of cycles or for an excessive exposure time. An EPROM with slow access time, may still program and work fine on an EPROM programmer, but beware that the EPROM programmer does not require or test for a fast access time. A worn out EPROM may program correctly yet fail to work in the equipment that requires a fast access time.

Ron (r273)

[brichter]

K+ for Ron... 

[ROCKET]

recently I had to point out to a ebayer --who holds 3---5 accounts all in great standing by the way .
that i purchased a arcade game board from him months ago .

that when he sold it said worked 100% tested . mind you the guy is a good sh&t ..done many dealings with him in past .


 but i noticed on many of his auctions pictures the labels covering the windws on the eproms had fallen off with age etc .

I emailed him ad said put some of the little round sticky paper over the hole in the eprom etc and dont take your pictures outside
in the sunlight --as he had been doing for yrs .. lol

exlplained that U.V. LIGHT erases info on eproms !!!

he said  never knew this and said it explains why in his dark shop the boards worked.
then many times after taking pictures the boards had created a problem of some type not all ------but he said 50%??

I think  he learned a valuable lesson after that email and ---watching his auction pictures now all eproms had a sticker over the hole lol

[Buzz]

I think we need Op-Bell !!  I seem to remember him saying you could not over erase a eprom.

Rocket I also seem to remember reading , it takes a year for natural U V to erase a eprom.

Now I seem to remember an awful lot for a old fart,  bet I'm wrong on at least one of the above  !!! Maybe both.

[StatFreak]

I think we need Op-Bell !!  I seem to remember him saying you could not over erase a eprom.
...

That's what he said, and I believe him.