Method to improve total dose radiation hardness in a CMOS dc-dc boost converter

MOSFETs used in space are subject to exposure to natural radiation in space. Among the effects of ionizing radiation are shifts in threshold voltage and reduction of carrier mobility. In this paper, total-dose effects in switching dc/dc boost converter are examined using SPlCE simulations. Then a new circuit design for an open loop dc/dc boost converter that is much less sensitive to radiation is proposed. By adding four more MOSFETs to the conventional design, good radiation hard behavior is observed under SPICE simulation. The improved design converter can work properly in a wide range of radiation environment, with increasing total dose radiation. The efficiency also greatly improves, and so does the leakage performance.