Proton radiation effects in XC4036XLA field programmable gate arrays

We have measured the proton-induced single-event upset (SEU) cross section of Xilinx XC4036XLA field programmable gate arrays. The threshold energy for SEU was determined to be (22+-2) MeV. The upset cross section saturated at a value of (2.7+-0.2*10/sup -9/ cm/sup 2//device. We have demonstrated that Bendel models are unable to describe the upset cross section. The effects of the radiation environment of the liquid argon calorimeter of the ATLAS detector on the XC4036XLA were estimated.