Understanding D/A converter architectures

摘要

Digital-to-analog converters (D/As) play an important role in many applications. Understanding the tradeoffs associated with common D/A architectures allows the most suitable D/A to be selected for an application. Conceptually, the simplest D/As use a binary-weighted architecture, where n-binary weighted elements (current sources, resistors or capacitors) are combined to provide an analog output (n = D/A resolution). Digital encoding circuits are minimized, but the difference between the MSB and the LSB weights increase with increasing resolution, making accurate element matching difficult High-resolution D/As using this architecture are difficult to manufacture and are sensitive to mismatch errors.