Research on Single Event Transients in Linear Voltage Regulators in a 28 nm Bulk CMOS Technology

Single event transients (SETs) sensitivity in two 28 nm bulk CMOS linear voltage regulators are studied by experiments and simulations. The differences between the two regulators are the structure of error amplifiers (EAs), load capacitance of EA, and size of power MOSFETs. The heavy ion experiments show that the SET responses of the two regulators have different amplitudes and widths. The SPICE simulation results reveal that the load capacitance of EAs can affect the amplitude of SETs. The sizes of power MOSFETs have little influence on the amplitude or width. The SETs in the regulator with the simply folded cascode amplifier have lower amplitudes and shorter widths than that of the regulator with the complementary folded cascode (CFC) amplifier. It is the size of MOSFETs that the capacitor on the gate node of power MOSFETs is charged through that determines the variation of transient amplitude. Moreover, the size of the transient width is determined by the size of the MOSFETs through which the capacitor on the gate node of power MOSFETs is discharged. The result of this article offers a reference for SET hardening.