A 4-bit Binary weighted Current Steering Digital To Analog Converter based on CNTFET

Abstract

In this work, we design and simulate a high performance Carbon Nanotube Field Effect Transistor (CNTFET) based current steering (CS) digital to analog-(DAC) circuit. The proposed DAC employs current steering technique with Simple Current Mirror, is a 4-bit with a sampling rate of 0.1G sample/sec, employing 32 nm technology node CNTFETs. A CS-DAC employing the conventional 32 technology node MOS has also been designed and compared with the proposed CNTFET based CS-DAC. The comparative analysis of various performance measuring parameters like integer non-linearity (INL), differential nonlinearity (DNL) glitch energy, power consumption etc. has been comprehensively performed. It has been observed that the unique properties of CNTs have made the proposed DAC to significantly outperform the conventional MOS technology based DAC. The static and dynamic performance of CS-DAC has been studied thoroughly at 0.9V power supply. It has been observed that in the proposed CNTFET based CS-DAC, INL and DNL have got decreased by 87.5% and 91.80% respectively in comparison to the conventional MOS based CS-DAC. Further, the dynamic performance measuring parameter like Spurious Free Dynamic Range (SFDR) has increased by 41.39 % and the power consumption has got decreased by ~53% in the proposed DAC in comparison to the conventional DAC. The glitch power in CNTFET based DAC has got reduced by 2.5 times in comparison to that in conventional DAC.