>>I have a couple of "ultraviolet" LEDs with me, but I doubt they are the
>>right frequency to erase EPROMs.
> If they're the high power UV LEDs then they should work. A friend of
> mine uses those to erase his EPROMs and the erase time is about the same
> as for a UV light.
There are not yet available UV LEDs that radiate at short enough wavelength
to erase EPROMs in a reasonable time. Most EPROMs will start to erase at
<400nm but take hours of exposure, to erase an EPROM in 20 mins or so needs
12mW/cm^2 of 257nm light on the die face. The longer wavelengths just warm
the chip up a bit.
This is why UV tubes for photo resist and similar won't erase EPROMs either,
they output nearer 400nm which is where state of the art UV LEDs are at.
Lee.
________________________________________________________________________
This e-mail has been scanned for all viruses by Star Internet. The
service is powered by MessageLabs. For more information on a proactive
anti-virus service working around the clock, around the globe, visit:
http://www.star.net.uk
________________________________________________________________________
Received on Thu Jul 29 2004 - 20:13:47 BST