22 Jan
2003
22 Jan
'03
12:08 p.m.
X-rays will erase the part at high energy levels, but this will also
degrade the part to the point where it
will fail soon, or die during erasure.
Arno Kletzander wrote:
Hello everybody, this is something I've been
wondering about for some time
now. Perhaps here is the place to ask, since it's about one of the "inner
secrets of silicon":
Tony Duell wrote:
The 8751 is the EPROM version of the 8051
microcontroller. It's otherwise
identical to it.
If it's in a ceramic package with a quartz window, then you can erase it
like any other EPROM and reprogram it. If it's in the plastic package,
then it's the OTP version.
If in fact the same die was used in both components, then it's only the
plastic (which is impenetrable to the commonly-used ultra-violet light) that
prevents the OTP variant from being erased and reprogrammed.
However, there are kinds of radiation similar to light which *will*
penetrate the plastic housing...you see where this goes? Will the memory be erased
when you, say, X-ray the OTP component, will it stay unaffected, or is the
thing just going to die?
(just outta curiosity)
Arno Kletzander