This paper shows a study about the heavy ion impacts effects on 28nm Fully Depleted Silicon On Isolator transistors (FDSOI). The use of an Hydrodynamic Charge Transport Model and a 3D TCAD simulation is detailed, with emphasis in Electron Density on FDSOI and total source current. The sensibility of drain region against this issues is shown. The simulation results shows an initial approach for future mixed-mode simulations in digital circuits at device level.