Identification of Sensitive Circuits by Selectively Simulating Total-Ionizing-Dose Effects for Analog - Mixed Signal Applications-combined

Abstract

A method that assists a radiation-hardened-by-design (RHBD) engineer to identify sensitive subcircuits for total-ionizing-dose (TID) in a complex circuit is presented and discussed. The method utilizes a combination of degraded and nondegraded models of transistors. This is demonstrated in a dual-frequency single-inductor multiple-output (DF-SIMO) buck converter, designed and fabricated in a 22nm FD-SOI technology, through circuit simulations. To do this, data-calibrated models of TID-induced behavior shown by the devices in this technology are implemented into the simulations. The purpose of this method is to increase the efficiency of identifying sensitive subcircuits, as they can consume a higher time-cost as the complexity of the circuit increases. The method involves simulating the effects of TID on the circuit, choose a subcircuit to subtract the effects from, and compare the results. Objective is to identify a block of circuitry that is the most sensitive in order to decide which subcircuits to harden.