An ultra-miniature broadband operational transconductance amplifier utilizing 10 nm wrap-gate CNTFET technology

Abstract

Operational Transconductance Amplifiers (OTAs) are the most pivotal blocks in analog circuits and systems. With the emersion of catastrophic short channel effects for Complementary Metal Oxide Semiconductor (CMOS) transistors at deep nanometric regime, the microelectronics scientists have focused on designing ultra-miniature OTAs based on non-silicon materials. During the last few years, Gate-All-Around Carbon Nanotube Field Effect Transistors (GAA-CNTFETs) with astonishing electrical and physical properties have drawn extensive attention of nanoelectronics researchers as a potential platform to represent high-performance nanoscale OTAs. In this regard, this work aims to propose an ultra-miniature ultra-wideband OTA based on the 10 nm GAA-CNTFET technology node. The proposed OTA benefits from the ballistic transport operation of the GAA-CNTFET transistors at ultra-scaled dimensions which provide a superior bandwidth (2.88 GHz) along with suitable power consumption (44.8 $$\upmu$$ W). The proposed OTA shows a 64.5 dB open-loop gain and a 59 dB common-mode rejection ratio at a 1 V supply voltage. Moreover, due to the utilization of the indirect feedback compensation method, the proposed GAA-CNTFET-based OTA presents an appropriate phase margin (61 $$^{\circ }$$ ) with a smaller compensator capacitor. With the mentioned performance metrics and occupying only 0.198 $$\upmu {\mathrm{m}^{2}}$$ physical area, the proposed GAA-CNTFET OTA has the potential to be considered as a replacement for nanoscale CMOS-based OTAs.