Название: Analog Devices and Circuits 2: Analog Circuits
Автор: Christian Gontrand
Издательство: Wiley-ISTE
Год: 2024
Страниц: 266
Язык: английский
Формат: pdf (true)
Размер: 17.8 MB

At the end of the Second World War, a new technological trend was born: integrated electronics. This trend relied on the enormous rise of integrable electronic devices.

Analog Devices and Circuits is composed of two volumes: the first deals with analog components, and the second with associated analog circuits. The goal here is not to create an overly comprehensive analysis, but rather to break it down into smaller sections, thus highlighting the complexity and breadth of the field.

The second volume deals with the circuits that "use" the analog components that were introduced in Volume 1. Here, a particular emphasis is placed on the main circuit: the operational amplifier.

SPICE (Simulation Program with Integrated Circuit Emphasis) is the standard for simulating analog circuits. Anyone who does not know this does not belong to the fraternity of electronic circuit analogists. SPICE is therefore the essential software for studying analog circuits.

The Chapter 2 investigates substrate coupling effects in mixed integrated circuits, particularly perturbations on radiofrequency (RF) blocks. The design and analysis of fully integrated voltage-controlled oscillators (VCOs) is one of the key points of RF analysis. First, sensitivity functions at the oscillation frequency of the control voltage, the bias current and parasitic sidebands due to the injected noise are extracted to discover a relationship between the noise of the substrate and the purity of the spectrum.

At the heart of the section, we try to develop quantitative predictions on the phase noise of these oscillators and give new leads in this field. Mixed-mode simulations are involved by applying a microscopic drift scattering model, while Kirchhoff’s laws govern the rest of the circuit used. Another problem for designers of complex heterogeneous circuits is predicting perturbations coming from switched logic gate blocks, flowing through the substrate to reach certain sensitive analog blocks. We present an application of a stochastic process model; the activity of digital switching is managed via Markov chains.

More and more system-on-chip designs require the integration of very fast analog circuits and large digital blocks. Until now, perturbations introduced by the digital part with respect to the analog part are a key problem and difficult to manage by designers, in particular, in the RF range. Pragmatically, the first objective of this chapter is to simply present the problem and propose some basic rules associated with a methodology and some tools to quantify and reduce the noise of the substrate in the future design, implied by the digital part, which will degrade the performance of analog circuits (RF). The problem in depth is to build efficient models for the activity of the digital part, the substrate and their coupling, in a package that could be integrated into a single computer-aided design (CAD) tool.

Three-dimensional (3D) integration is perhaps the most promising technological solution to keep up with the level of integration dictated by the famous Moore’s law, and not just for a few niches. From the beginning of the millennium, it has led to important research work. It allows different circuits and devices to be superimposed in a single package. Its main advantage is to allow a combination of heterogeneous and highly specialized technologies for the constitution of a complete system, while preserving a very high level of performance due, in particular, to very short connections between these different circuits or strata.

One of the objectives of this book is to provide models of substrates coupled with their internal connections and/or contacts through/in the substrate with several degrees of finesse/precision to allow high-level designers to manage and especially to optimize the partitioning between different strata. This modeling involves developing several views at different abstraction levels: from the physical model to the “high-level” model.