A 5 V, 118 dB /spl Sigma//spl Delta/ analog-to digital converter for wideband digital audio

Digital signal processing can replace analog signal processing in professional audio equipment only when analog-to-digital converter dynamic ranges approach 120 dB. Super-high-end audio applications extend the audio band beyond 30 kHz and require 96 kHz sampling frequency. This paper describes a multi-bit /spl Sigma//spl Delta/ modulator developed for high-end digital audio. The modulator is a single-loop, seventh-order type with a 3-level quantizer. The modulator samples the analog input at 6.144 MHz and has 140 dB signal-to-quantization noise in a 48 kHz bandwidth. The device is fabricated in a double-poly, double-metal, 0.8 /spl mu/m CMOS process.