UPSET: Direct Ionization-induced SEE Rate Calculation

Overview

UPSET is a more complicated program that calculates the upset rate from the direct ionization of particles originating outside the spacecraft. UPSET assumes that each bit is stored in a microcircuit which has one continuously sensitive node. This node is surrounded by a sensitive region which is assumed to have the shape of a rectangular parallelepiped. To calculate the upset rate using UPSET, one must first use LET to create an integral LET spectrum. UPSET then integrates this spectrum over the differential distribution of pathlengths through the sensitive region of the one sensitive node in the microcircuit to obtain the SEU rate.

Inputs

UPSET's input parameters are:

• The critical charge required to produce an SEU in the device
• The linear dimensions of the parallelipiped representing sensitive region of a microcircuit
• The name of a file containing the input integral LET spectrum

Outputs

UPSET outputs upsets/(bit-sec) and upsets/(bit-day).