Sigma-Delta Converters: Practical Design Guide, 2nd Edition

6 Automated Design and Optimization of Ms

As stated in Chapter 5, the design of Ms involves a number of tasks at several abstraction levels, usually addressed by following a top‐down/bottom‐up systematic methodology – from specifications to die implementation. In such an iterative process, it is a common practice for designers to put a lot of effort into optimizing the design of their circuits at transistor level, trying to reduce the power dissipation as much as possible, while keeping the electrical characteristics required by the target specifications. However, in the majority of practical situations, the actual bottleneck is not at the circuit or device level but at the system level, where correct selection of the modulator architecture, loop‐filter topology, coefficients, and so on can lead to a more efficient and robust design, while relaxing the design margins in the most critical metrics at electrical level.

Bearing this in mind, this chapter deals with some of the relevant design methods and CAD tools intended for the automated high‐level synthesis and optimization of Ms, considering how they can be combined to help designers find the best M design for a given ...