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GADFRAN
May 26th, 2011, 07:06 PM
Are flash / thumb drives and memory cards sensitive to magnets like other magnetic media e.g., floppy disks / hard drives ?

I thought that files were saved to a special chip on these devices so they were not as sensitive to magnets.

Wikipedia does not seem to clarify this.

Thanks !

Frank

lutiana
May 27th, 2011, 12:40 AM
I do not believe that they are as susceptible to magnetic interference as magnetic media is.

Tor
May 27th, 2011, 12:54 AM
They're not susceptible to normal magnetic fields (but they probably won't like to be inside a medical magnetic scanner), but the _are_ susceptible to static electricity. If you zap the flash memory you may find all content gone.

Chuck(G)
May 27th, 2011, 01:09 AM
Information on a flash drive is stored as a charge on floating gate. There is no magnetic interaction.

However, a Microdrive (miniature hard disk) will certainly be affected by a strong magnetic field.

lutiana
May 27th, 2011, 01:13 AM
Information on a flash drive is stored as a charge on floating gate.

Does this mean that over time you will lose your data due to the degradation of the charge?

carlsson
May 27th, 2011, 01:42 AM
Many of us probably have had the joy of feeding SD memory cards and USB sticks through the security X-ray at airports. I've done it a few times, without no apparent damage from the brief scanning.

Tor
May 27th, 2011, 03:36 AM
Does this mean that over time you will lose your data due to the degradation of the charge?
Yes. I've seen varying numbers. down to a couple of years or less, and up to five or ten. Ten sounds particularly unlikely. I would refresh/re-backup at least every two years, or yearly to be sure.

commodorejohn
May 27th, 2011, 06:46 AM
Yes. I've seen varying numbers. down to a couple of years or less, and up to five or ten. Ten sounds particularly unlikely. I would refresh/re-backup at least every two years, or yearly to be sure.
Personally, I wind up replacing mine that often anyway...they're rarely built for the connector to last as long as the flash does...

RetroHacker_
May 27th, 2011, 07:56 AM
Flash drives are impervious to magnetic fields. The biggest danger to flash drives is losing the damn things.
Also, don't leave them in your pocket on laundry day. Did that once, the drive worked for a while afterwards, but then failed, I took it apart to find corrosion on the board.

-Ian