Background and State of the Art

Abstract

This chapter presents the background and the state of the art in the broad field of single-stage amplifiers, providing the context of the work developed. The performance metrics considered in this work are defined and detailed, namely, low-frequency gain, gain-bandwidth product, energy-efficient figure of merit, input-referred noise, and offset voltage. Moreover, notions on stability and frequency compensation are given. Operational amplifiers and operational transconductance amplifier topologies are explored, and dynamic amplification is addressed. The background and initial considerations are presented in Sect. 2.1; an overview on amplifiers, namely, single-stage architectures, is presented in Sect. 2.2; the important performance metrics considered throughout this work are described in Sect. 2.3; the operational transconductance amplifier is described in Sect. 2.4; and in the following sections, the most relevant architectures of single-stage amplifiers are described: Sect. 2.5 addresses elementary cascode amplifiers; Sect. 2.6 presents the recycling folded-cascode amplifier; and finally, dynamic amplifiers and the corresponding theory are addressed in Sect. 2.7.