Utilization of Negative-Capacitance FETs to Boost Analog Circuit Performances

Abstract

Negative-capacitance FETs (NCFETs) are a promising candidate for low-power circuits with intrinsic features, e.g., the steep switching slope. Prior works have shown potential for enabling low-power digital logic and memory design with NCFETs. Yet, it is still not quite clear how to harness these new features of NCFETs for analog functionalities. This article provides more insights into the circuit design space with new device characteristics and investigates its deployment in analog circuits, specifically, time-domain analog-to-digital converters (ADCs) and phase-locked loops (PLLs). We propose and optimize a novel digital-based clocked comparator and a capacitor-based voltage-to-time converter (VTC), which are essential building blocks in ADCs and PLLs. Evaluation results show beyond-FinFET comparison speed and enhanced linearity for the proposed NCFET-based clocked comparator and VTC, respectively. Such improvement is achieved by exploiting the steeper slope and increased output impedance of NCFETs. More details on design details and a discussion are provided in this article.