Bio-inspired devices, circuits and systems

Despite their enormous computational powers, digital computers today are inferior to humans in such tasks, like seeing events happening in front, perceiving and recognizing them by intuition and association, and making a decision to take an immediate action. It is very unlikely that computers will become intelligent as humans in this sense by just increasing the number of transistors on CPU chips. How can we approach this problem by learning from biological systems of their computing principles? This is the main theme of this article. We are aiming to develop a new-paradigm computing system most suited to such human-like intelligent information processing by best utilizing the state-of-the-art silicon technology. For this end, we have developed a series of VLSI chips dedicated to specific brain-mimicking processing using digital, analog as well as mixed-signal circuit technologies. There is an opportunity of even using exotic current-voltage characteristics of nano functional devices directly in such computation. In this paper, we will also discuss how we can circumvent the serious issue of the nanoscale integration, i.e., the variability problem of device characteristics that is inherent in nanoscale devices.