Reliability improvement and online calibration of ICs using configurable analogue transistors

Reliability of electronic circuits over an extended temperature range is a critical consideration in demanding applications such as aerospace and the military. Achieving this reliability on modern deep submicron process nodes is a significant challenge especially for analogue circuits due to the high level of device variability. A novel approach is proposed in this paper that employs online adjustment of configurable analogue transistors (CATs) to address this challenge, significantly improving the consistency of circuit performance over temperature. The proposed method involves optimally sizing configurable devices for temperature and process variation and then employing a calibration lookup table during normal operation to compensate for temperature shifts. In the presented case study of an instrumentation amplifier, the CAT approach is shown to successfully mitigate temperature induced performance loss, demonstrating significant calibration potential and reliability improvement. These advantages are enjoyed at minimal cost in terms of area and complexity overhead, and the process of implementing the circuit changes is highly automated. The promising results detailed in this work demonstrate that the CAT technique has useful applications in the area of reliability improvement for demanding environments.