A method for preventing snap-back in a circuit including at least one MOS transistor having a parasitic bipolar transistor associated with it includes coupling a circuit node including at least one source/drain node of the at least one MOS transistor to a bias-voltage circuit and enabling the bias-voltage circuit to supply a potential to the at least one source/drain node of the at least on MOS transistor, the potential having a magnitude selected to prevent the parasitic bipolar transistor from turning on.