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I have an SRAM memory device GM76C88AL with this datasheet. The RAM was exposed to a radioactive beta source (~2MeV) for some time (about 2 hours). The source was just right above it (placed on it), in the upper middle part of the IC.

Now, when I write H's in memory, the bits are not correctly written. Some of them are zeros. I've done a routine to sweep the memory and write H's on all addresses, but when I read it, some are zeros. The same routine works correctly for a memory (of the same model) that was not exposed.

The zero bits are not always the same for each time the memory is read-written. More L's appear if I try to write to higher memory addresses. My guess is that, maybe one of the decoders, or the column-selector, was affected in the RAM logic or degenerated. What may be causing this behavior of the IC?

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    \$\begingroup\$ Any and all parts are affected by the radiation so any and all internal block may malfunction in any way. \$\endgroup\$
    – Justme
    Commented Jun 17 at 20:06
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    \$\begingroup\$ nepp.nasa.gov/DocUploads/D41D389D-04D4-4710-BBCFF24F4529B3B3/… \$\endgroup\$
    – Mattman944
    Commented Jun 17 at 20:56
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    \$\begingroup\$ Would you mind to put your question directly in the title, not the observation that raised the question, please? I came here with "Of course, if you damage a RAM, it will not work properly." \$\endgroup\$
    – the busybee
    Commented Jun 18 at 5:46
  • \$\begingroup\$ 2 MeV beta sources are at the very high end of such emitters. I think 3 MeV is about as high as they go. The impacts are, by definition, random. What kind of answer are you hoping to see?? What exact source did you use? (Just curious.) \$\endgroup\$
    – periblepsis
    Commented Jun 18 at 12:40

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