Designing a Delta-Sigma AD Converter

While there are plenty of textbook materials explaining the system-level behavior and mathematics behind Delta-Sigma ($\Delta\Sigma$) analog-to-digital converters, translating those ideal concepts into solid transistor-level LSI circuits is an entirely different challenge.

This practical guide is written specifically for circuit design engineers, semiconductor professionals, and graduate students who want to see how a Delta-Sigma ADC actually functions down to the individual PMOS and NMOS transistors. Using the completely free software LTspice, this book bypasses academic fluff to provide a clear, visual, and quantitative walkthrough of a complete first-order Delta-Sigma ADC design.

Every key element circuit—including bootstrap switches, switched-capacitor integrators, comparators, DFFs, and operational amplifiers—is presented alongside its complete schematic and standalone simulation waveforms.

Furthermore, this book goes beyond simple functional checks. You will learn exactly how to evaluate and calculate critical IC performance metrics directly within LTspice, including INL, DNL, FFT analysis, Noise Shaping, SNR, and ENOB. To give you the ultimate practical reference, the text directly compares a Single-Ended configuration against an advanced Differential-Output configuration, backed by raw simulation logs and calculated worked examples.

Whether you are starting your first LSI design project or looking to solidify your understanding of mixed-signal simulation, this book serves as your concrete, hands-on foundation.