Work

Design of an ultra-wideband 85.79 GHz 32 nm CNTFET current-starved ring VCO with −220.07 dBc/Hz FoM using the $$g_{m}/I_{D}$$ approach

Year: 2026

Type: article

Abstract: This paper presents a high-performance current-starved ring voltage-controlled oscillator (CSVCO) designed using carbon nanotube field effect transistors (CNT-FETs). A distributed variable capacitance scheme is employed to modulate the tuning voltage across individual oscillator stages, thereby significantly enhancing the oscillation frequency and tuning range while maintaining power efficiency and achieving a superior figure of merit (FoM). The design methodology, based on the transconductance-to-current efficiency ( $g_{m}/I_{D}$ ) approach, provides a technology-independent framework for simplified sizing and biasing, improves power efficiency, and offers clear insight into device operating regions. The design is simulated using a 32 nm CNTFET technology node in the Cadence Virtuoso environment. The proposed CNT-FET-based current-starved ring VCO (CN-CSVCO) achieves an oscillation frequency of 85.79 GHz, a tuning range of 197.72 %, and consumes only 9.41 $\mu$ W of power at a control voltage of 0.4972 V. Furthermore, the design exhibits a phase noise of $-$ 101.145 dBc / Hz and a FoM of $-$ 220.07 dBc / Hz . These results demonstrate that CNT-FET-based VCOs can deliver high-frequency and energy efficiency, making them promising for next-generation millimeter-wave communication systems.

Source: Scientific Reports

DOI: 10.1038/s41598-026-56558-7

Authors: Ganesamoorthy B., Abdul Majeed K. K., Antony Xavier Glittas X.

Institution: Vellore Institute of Technology University

Language: English

Topic: Radio Frequency Integrated Circuit Design

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,690

Funder: VIT University