A CMOS Current-Mode Dynamic Programming Circuit

Abstract

Dynamic programming (DP) is a fundamental algorithm for complex optimization and decision-making in many engineering and biomedical systems. However, conventional DP computation based on digital implementation of the Bellman–Ford recursive algorithm suffers from the “curse of dimensionality” and substantial iteration delays which hinder utility in real-time applications. Previously, an ordinary differential equation system was proposed that transforms the sequential DP iteration into a continuous-time parallel computational network. Here, the network is realized using a CMOS current-mode analog circuit, which provides a powerful computational platform for power-efficient, compact, and high-speed solution of the Bellman formula. Test results for the fabricated DP optimization chip demonstrate a proof of concept for this solution approach. We also propose an error compensation scheme to minimize the errors attributed to nonideal current sources and device mismatch.