Characterization of a Gm-C Filter Based on CNTFETs for Use in Digital Audio Broadcasting Systems

Abstract

Anti-aliasing filters play an important role in analog front-end circuits, and their suitable design can improve the performance of digital audio broadcasting systems. In this paper, a Gm-C anti-aliasing filter based on carbon nanotube field effect transistors (CNTFETs) is proposed. Using CNTFETs provides low power consumption and appropriate frequency response. Simulation results show that these characteristics are widely dependent on the physical parameters of CNTFETs. The effects of chirality, the number of CNTs in each CNTFET, and distance of CNTs from each other on power consumption and frequency response are investigated. Among these parameters, the chirality and number of CNTs respectively have nonlinear and linear relationships with both power consumption and cutoff frequency. On the other hand, changing the distance between CNTs has the least effect on the output characteristics. Also, the output features of the filter for different gate oxides and channel lengths are studied. The overall result of the simulations demonstrates that the filters based on CNTFETs are promising candidates to be used in future nano-scale integrated circuits.