This course gives the PhD student a basic knowledge about two kinds of fundamental mixed-signal circuits, i.e. A/D and D/A converters, which are becoming increasingly important in modern electronic systems. While the largest part of signal processing is undoubtedly performed in the digital domain, very often the input and/or the output of the system is analog: as examples, we can mention the power amplifiers in digital audio, screens and monitors in digital video, and the antenna in radio communications, all applications that typically require high performance A/D and D/A converters. In fact, very diverse fields such as radio communications, wireline communications, hearing aids, and, in general, all kinds of embedded systems, are experiencing a very strong push to move the converters closer and closer to the user interface, in an effort to enter the robust and design-friendly digital domain as soon as possible. As a consequence, the performance of the A/D and D/A converters is a key parameter in the overall quality of many commercial ICs in terms of conversion speed, signal range, power consumption, and area.