All our product uses SS hardware so magnetized screw drivers do not help, but one of our old timers techs that deals with testing of boards said: Magnetized screw drivers scramble the programs. So it is not about erasing the program but altering it. One or many transistors that switches from high to low will alter the program. It may not happen all the time, but if it happened one time in a hundred it would be one too many. I tried to get something in writing about this possibility from big companies that build EPROMs. Some did not response and one said that the fellow that did this kind of experiments retired. When ever the right time comes, I will do some experiments and get back with you.
Regards,
Ramon
-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of George Patrick
Sent: Wednesday, March 23, 2005 4:24 PM
To: [log in to unmask]
Subject: Re: [TN] Magnetic Screwdrivers
OK. I have looked at the postings.
I still see nothing that would lead me to believe that a weak magnetic field
could erase an EPROM. Last time I heard, EPROMS were programmed by
electrical charge (the programming cells are capacitors) and a weak magnetic
field shouldn't induce enough current to change that charge. I would buy an
High power X-ray erasing them, the current induced by that could be enough
to change the charge and do the job. I just don't see it happening from the
gauss produced by a magnetized screwdriver tip.
I would still like to see any current references to the contrary if I am
wrong, though :)
--
George Patrick
Tektronix, Inc.
Central Engineering, PCB Design Group
P.O. Box 500, M/S 39-512
Beaverton, OR 97077-0001
Phone: 503-627-5272 Fax: 503-627-5587
http://www.tektronix.com http://www.pcb-designer.com
It's my opinion, not Tektronix'
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Bloomquist, Ken
Sent: Wednesday, March 23, 2005 12:45
To: [log in to unmask]
Subject: Re: [TN] Magnetic Screwdrivers
I would check the TechNet archives. There was a pretty extensive discussion
on this subject a few months ago.
KennyB
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