The purpose of this work is to present one investigation utilizing a pulsed laser as a tool to improve the Single Event Upset tolerance of a memory cell. These results coming with a previous ion testing evaluation of the circuit allow an optimization of the design. The laser results permit a more detailed analysis of the phenomenon leading to the upset and a precise localization of the most sensitive areas. As a result the behavior verification of the design combined with the use of robust elementary blocks strengthens the hardening capabilities of the cell.