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Could a customs x-ray corrupt sram data? Programming RTC on one side of the world, then transporting to the other side has worked fine in the past. The majority of a recent batch all had corrupted memory https://www.maximintegrated.com/en/products/digital/real-time-clocks/DS1500.html Thanks. BW.

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    \$\begingroup\$ The answer is YES. Of course. In fact, SEU (single event upsets) of SRAM and DRAM has been used by researchers as a method for detecting xrays. Use google to search on the use of memory chips as xray detectors. In fact, Customs uses them to detect radioactive devices, themselves! So they better not argue with you about it. They know, too. \$\endgroup\$ – jonk Oct 24 '16 at 3:25
  • \$\begingroup\$ A few references: inf.ufrgs.br/~fglima/lima_proposal.pdf and etd.library.vanderbilt.edu/available/etd-07082014-082801/… as well as the often cited, Travis Z. Fullem. "Radiation Detection Using Single Event Upsets in Memory Chips." Masters Thesis, State University of New York at Binghamton, Vestal, NY, February 2007, which focuses specifically on gamma radiation. \$\endgroup\$ – jonk Oct 24 '16 at 19:11
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There is evidence of slight shifts in stored information on floating gates shifting from cargo X-rays, however RAM should be pretty immune- especially to wholesale corruption.

It's possible that something you are doing is causing X-rays or charged particles to be sprayed around the vicinity, from whatever they are using to probe the cargo. For example, attempts to shield with some metals actually makes things worse.

You might want to investigate the routing of the cargo from your door to the other side.

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  • When energy excites a single molecule sufficiently to stimulate a free electron to escape it's orbit , then a single electron of charge is allowed to flow. This flow of charge per unit time is what we define as current.
  • When this flow of charge per unit time accumulates in a dielectric such as a tiny capacitor, the voltage accumulates or integrates in that direction to create a voltage and then stops when the energy is removed.
  • The Photon energy at UV, X-Rays and Gamma Rays are increasing higher emissive energy at shorter wavelengths or higher f and is defined by the Plank-Einstein equation. E=hf

(warning opinion)

I would expect NAND-Flash RAM to be far more sensitive than SRAM. The reason is the impedance of the memory cell is high whereas SRAM is a low impedance transistor cell out of 8 used and biased by a backup battery.

But I have heard of mobile memory contents being altered in some transmission type Airport X-RAY scanners (not background types), but again I suspect it is Flash RAM. ( so called non-volatile )

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