Single-event upset

The state change is a result of the free charge created by ionization in or close to an important node of a logic element (e.g. memory "bit").

In 1979, James Ziegler of IBM, along with W. Lanford of Yale, first described the mechanism whereby a sea-level cosmic ray could cause a single-event upset in electronics.

1979 also saw the world's first heavy ion "single-event effects" test at a particle accelerator facility, conducted at Lawrence Berkeley National Laboratory's 88-Inch Cyclotron and Bevatron.

[3] Terrestrial SEUs arise due to cosmic particles colliding with atoms in the atmosphere, creating cascades or showers of neutrons and protons, which in turn may interact with electronic circuits.

In space, high-energy ionizing particles exist as part of the natural background, referred to as galactic cosmic rays (GCRs).

Solar particle events and high-energy protons trapped in the Earth's magnetosphere (Van Allen radiation belts) exacerbate this problem.

The high energies associated with the phenomenon in the space particle environment generally render increased spacecraft shielding useless in terms of eliminating SEUs and catastrophic single-event phenomena (e.g. destructive latch-up).

SRAM memories are usually designed with transistor sizes close to the minimum allowed by technology to allocate the maximum number of bits per unit area.