This paper presents a modeling approach of single-event functional interrupt (SEFI) which takes into account all the physical and electrical processes from the radiation particle down to the event at the system level. This paper is focused on the evaluation of SEFI sensitivity by experimental and simulation analyses of a readout integrated circuit (ROIC) designed by Sofradir for their infrared image sensors. Relevant correlations between simulation and experimental results of SEFI cross sections for heavy ions are presented and discussed. The simulation results confirm the strong SEFI robustness of the ROIC at 57 K.