*This post is part of a series on delta-sigma techniques: analog-to-digital and digital-to-analog converters, modulators, and more. A complete list of posts in the series are in the How Delta-Sigma Works tutorial page.*

Today I’d like to turn to the fascinating topic of delta-sigma techniques. Delta-sigma is best known for its use in analog-to-digital and digital-to-analog converters, but it also has a potent role in digital signal processing and even in analog applications. By its nature, delta-sigma can reduce the amount of analog circuitry needed in a radio or other electronics, and what is left is often simpler and cheaper than what would otherwise be required.

Beyond that, delta-sigma techniques are nifty! The core concept is counter-intuitive at first glance, yet it offers all kinds of powerful applications. Working at understanding delta-sigma techniques gives deep insights to many other areas of signal processing.

This is the first of a multi-part series on delta-sigma, which is too broad and deep a topic to cover in a single post. There will be some math, balanced with an intuitive approach to the circuits. I will also delve into the the practical, building delta-sigma data converters and sharing the schematics and results. I will be learning about delta-sigma along with you, so stay tuned for more in future posts.

The place to begin is with a first order delta-sigma modulator, which is the simplest variety of delta-sigma circuit. A first-order modulator has a structure like this:

Continue reading “How Delta Sigma Works, part 1: Introducing the Delta Sigma Modulator”