Evaluation Method by High-Speed 1-Bit Stream for Digital Audio System

In digital audio systems, the Delta Sigma modulator has been widely utilized as a digital-to-analog converter (DAC) for Class-D amplifiers and as an analog-to-digital converter (ADC). To evaluate the Delta Sigma modulator, generally, a high-accuracy analog signal generator and some expensive band-pass filters are required. For this reason, a low-cost evaluation method using a 1 bit stream is proposed [1]; however, it cannot measure recent high-sampling-rate Delta Sigma, modulators in real time. In this paper, we realize a real-time evaluation system that can measure such a high-sampling-rate Delta Sigma, modulator.