Monte Carlo Simulation of Proton Upsets in Xilinx Virtex-II FPGA Using a Position Dependent ${\rm Q}_{\rm crit}$ With PROPSET

Proton upsets, predicted by the software code, PROPSET, for the Xilinx Virtex-II FPGA and other devices are presented. PROPSET uses heavy-ion upset data to determine the upset energy threshold at each position within the device's sensitive volume. Sensitivity to the shape and thickness of the sensitive volume, to the choice of Weibull parameters and to model physics are explored