Analog-to-Digital (A/D) Converters

An A/D converter converts analog input signals into digital output data in many areas such as process control, aircraft control, and telemetry. Being the interface between analog systems and digital systems, it plays a key role in many industrial, commercial, and military systems. Several types of A/D converters exist: counter-controlled, successive-approximation, and dual-ramp (dual-slope) converters. One should understand its basic operation because analog comparators formthe basis of A/D converters. Figure shows the block diagramof an analog comparator. The commercially available LM311 is an example that is widely used by designers.