Evaluation system for digital audio by 1-bit stream using FPGA

In digital audio systems, the ΔΣ modulator has been widely utilized as a Digital-to-Analog Converter (DAC) for Class-D amplifiers, and an Analog-to-Digital Converter (ADC). In general, to evaluate the ΔΣ modulator, an expensive analog signal generator or high-performance DAC is required. In this paper, we realize a novel system using a Field-Programmable Gate Array (FPGA), PC, and power supply. Our system allows evaluation of the ΔΣ modulator using a 1-bit stream instead of an analog signal.