29 Jul
2004
29 Jul
'04
1:51 p.m.
On Fri, Jul 30, 2004 at 02:13:47AM +0100, Davison, Lee wrote:
I will have to check, but IIRC, my LEDs are 450nm.
-ethan
--
Ethan Dicks, A-130-S Current South Pole Weather at 30-Jul-2004 01:50 Z
South Pole Station
PSC 468 Box 400 Temp -89.9 F (-67.7 C) Windchill -125.8 F (-87.7 C)
APO AP 96598 Wind 7.9 kts Grid 084 Barometer 661.8 mb (11319 ft)
Ethan.Dicks(a)amanda.spole.gov http://penguincentral.com/penguincentral.html
>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.