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Category Archives: Design Notes
This post is part of a series on delta-sigma techniques: data converters, modulators, and more. A complete list of posts in the series are in the How Delta-Sigma Works tutorial page. In the first installment of How Delta-Sigma Works, I presented … Continue reading
PCB layout is fun, especially when you are trying to eke the best performance out of a component. Last week, I finished the PCB layout for the AK5388 analog-to-digital converter (ADC) I chose for my digital ham radio transceiver project. … Continue reading
Hans Remeeus PA1HR has compiled QST‘s performance measurements for dozens of recent rigs into a single, easy-to-read table. It’s perfect for anyone shopping for a new rig. It’s also great for numerically inclined homebrewers. I have been wishing for something like this … Continue reading
The old saw goes, “oscillators don’t, amplifiers do”, but that’s an analog saying. It doesn’t apply to the digital world. After all, digital is easy, while analog is hard, right? (Be careful not to answer too quickly!) For the last … Continue reading
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, let’s take another look at delta-sigma conversion. The … Continue reading
Some months ago, I came across an Actel app note that advocated using FPGAs as level shifters. “What a crazy waste of computing power,” I thought to myself, “though I suppose they are just trying to sell the low-end ProASIC3 nano FPGAs.” With that, I set the thought aside.
Much later, I ran into a problem. Continue reading
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. Continue reading