Ternary Arithmetic Logic Unit Design Utilizing Carbon Nanotube Field Effect Transistor (CNTFET) and Resistive Random Access Memory (RRAM)

Abstract

Due to the difficulties associated with scaling of silicon transistors, various technologies beyond binary logic processing are actively being investigated. Ternary logic circuit implementation with carbon nanotube field effect transistors (CNTFETs) and resistive random access memory (RRAM) integration is considered as a possible technology option. CNTFETs are currently being preferred for implementing ternary circuits due to their desirable multiple threshold voltage and geometry-dependent properties, whereas the RRAM is used due to its multilevel cell capability which enables storage of multiple resistance states within a single cell. This article presents the 2-trit arithmetic logic unit (ALU) design using CNTFETs and RRAM as the design elements. The proposed ALU incorporates a transmission gate block, a function select block, and various ternary function processing modules. The ALU design optimization is achieved by introducing a controlled ternary adder–subtractor module instead of separate adder and subtractor circuits. The simulations are analyzed and validated using Synopsis HSPICE simulation software with standard 32 nm CNTFET technology under different operating conditions (supply voltages) to test the robustness of the designs. The simulation results indicate that the proposed CNTFET-RRAM integration enables the compact circuit realization with good robustness. Moreover, due to the addition of RRAM as circuit element, the proposed ALU has the advantage of non-volatility.

Low power CNTFET-based ternary multiplier for digital signal processing applications

“…Binary systems describe voltage levels 0 and V DD with two logic values, 0 and 1. Ternary logic circuits have three stable states (0, 1 and 2) that are used to build a digital circuits [22] [23]. The voltage value of ternary systems is tabulated in table 1.…”

Carbon nanotube field effect transistors: an overview of device structure, modeling, fabrication and applications

“…In comparison to conventional designs, a significant reduction in transistor count was demonstrated, along with lower power consumption and improvements in latency and the noise margin [113]. CNTFETs with resistive random access memory (RRAM) were offered as design features for non-volatile ternary logic gates by Zahoor et al [58,[114][115][116][117]. Instead of using huge devices (resistor) to achieve ternary logic gate, the design used activeload RRAM and CNTFET.…”

Resistive random access memory: introduction to device mechanism, materials and application to neuromorphic computing

“…Thus, novel data processing technologies need to be explored to critically address the issue of insufficient computing capacities particularly in "memory" which nowadays constitutes about 60% of the processor area thus constituting for the major target of the designers for device miniaturization. Presently, researchers in nanoelectronics field are focusing their efforts on resistive random access memory (RRAM) which is one form of memristor technology as a feasible option for existing CMOS-based device miniaturization [5][6][7][8][9][10][11][12][13]. The research in RRAM continues to witness a tremendous growth as it is seen as the promising alternative to existing CMOS devices owing to its numerous advantages such as scalability, high data retention, CMOS and 3D integrability, multistate programmability, good endurance, lower power consumption and relatively high speed [14].…”