Quantification, modelling and design for signal history dependent effects in mixed-signal SOI/SOS circuits

Abstract

Starting from the basis that device matching is central to most analogue designs, the effects of static and dynamic signal history dependence on post-radiation device characteristics and analogue circuit cell performance are examined. The effects of unbalanced static and dynamic bias signals on matched devices subject to radiation is studied. Behavioural models for comparator cells and complete analogue to digital (A/D) converters are developed to assess the impact at cell and system level. New circuit design techniques are used too in the implementation of a 7-bit flash A/D converter fabricated in 1.5 /spl mu/m SOI/SOS CMOS; and measurements confirm that performance remains consistent up to very high dose levels.