CNTFET based design of content addressable memory cells

Abstract

Carbon Nanotube Field-Effect Transistor (CNTFET) with 1-D band structure providing high carrier velocity on account of ballistic transport operation and low OFF current capability has proved to be a promising alternative to the conventional CMOS technology. This paper presents novel designs of content addressable memory (CAM) cells using CNTFETs. A CAM performs parallel data comparison with data storage. Binary CAM (BCAM) performs exact-match searches while Ternary CAM (TCAM) provides an added flexibility of pattern matching with the use of don't care. HSPICE simulation results are reported to show that the three memory operations of the proposed CAM cells perform correctly at 0.9 V power supply. It is also shown that the presented BCAM and TCAM cell achieves a great improvement in search delay by 84% and 75% respectively compared to CNTFET based conventional cells.