Quantized Level Systems: Digital‐to Analog and Analog‐to‐Digital Conversions
Pierre Muret · 2018
Systems that establish a relationship between a signal represented by a continuous function or an analog signal, and a signal represented by an integer or quantized signal, perform approximations that can be represented by a multistep function. Up to the quantization error, the system is correctly a linear system. The power of the quantization noise is significant up to the frequencies of the order of the sampling frequency or the inverse of the time needed to complete the conversion. The two types of conversion are performed either by means of digital-to-analog converters (DACs), or analog-to-digital converters (ADCs). “Sigma-delta” conversions implement analog and digital operations that borrow most of their modeling from the field of sampled systems. The “sigma-delta” technique is dependent on the implementation of modulators processing the sampled analog signal, most often achieved using switched-capacitor circuits.