To address the new space market focused on cost reduction, the use of COTS (circuit on the shelves) products is a good option. To be compliant with space reliability, COTS must be evaluated and modified to meet space agency specifications, especially on Single Event Latchup (SEL). This effect occurs by the strike of a heavy ion on the circuit. The transmitted energy to the matter (LET) triggers the parasitic thyristor and induces the latchup. The SEL sensitivity is characterized by the LET threshold and the holding voltage criteria. Until now, to evaluate LET threshold, TCAD simulation and experimental tests were performed, but TCAD is time consuming and irradiation sessions are very expensive. An analytical model LET threshold is a solution to obtain a quick estimation at lower cost and could help to harden the product to radiation. JMP is well adapted to assist in building and analyzing the results of a design of experiment (DOE). Its profiler is adapted to find best combination of the inputs to meet LET threshold criteria.