99-dB High-Performance Delta-Sigma Modulator for 20-kHz Bandwidth

In this paper, we present a fourth-order single-bit delta-sigma modulator with wide dynamic range. This modulator is suitable for distributed sensor and audio codec applications. This chip was fabricated in a 0.18- mum one-poly, four-metal CMOS technology, and occupies 1.22-mm
²
active area. The circuit is clocked at 3.2 MHz and the overall power consumption is 5.6 mW from a 3.0 V power supply. Experimental results show a maximum dynamic range of 99 dB within a 20- kHz bandwidth.