A microcontroller comprising a central processing unit and a further fault processing unit suitable for performing validation of operations of said central processing unit. The further fault processing unit is external and different with respect to said central processing unit and said further fault processing unit comprises at least a module for performing validation of operations of said central processing unit and one or more modules suitable for performing validation of operations of other functional parts of said microcontroller. Validation of operations of said central processing unit is performed by using one or more of the following fault tolerance techniques: data shadowing; code&flow signature; data processing legality check; addressing legality check; ALU concurrent integrity checking; concurrent mode/interrupt check. The proposed microcontroller is particularly suitable for application in System On Chip (SoC) and was developed by paying specific attention to the possible use in automotive System On Chip. The invention also includes a method for designing and verify such fault-robust system on chip, and a fault-injection technique based on e-language.
