EPROM erase times and lifespan

[Dave McGuire]

On Jan 29, 2009, at 10:42 AM, Mr Ian Primus wrote:
>> Presumably more expensive erasers do things in-place - i.e.
>> periodically do a blank-check during the erase cycle?
>
> Hmm, I've never even heard of such a device. Even the professional  
> EPROM erasers are little more than what I've built, a box with a UV  
> light and a timer. I've never heard of an eraser in which the chip  
> was actually connected to anything while being erased.
>
> If a machine like this exists, however, it would be quite cool! But  
> probably very expensive, and a pain in the neck to use, as you'd  
> have to tell it what kind of chip you were erasing, and it would  
> need ZIF sockets and all kinds of electronics to read the chips.

   It would be neat, but kinda pointless.  Leaving them in the eraser  
for too long will definitely fry them, but it's not a matter of "five  
minutes too long and it's toast".

   I leave chips in the eraser for 20 minutes, and it's good for  
everything I use, which is usually higher-capacity EPROMs, but  
sometimes EPROM-based MCUs and UV PALs.

           -Dave

-- 
Dave McGuire
Port Charlotte, FL