Broadband Continuous-Time Sigma-Delta Analog-to-Digital Conversion Using MOSIS AMI 0.5 um CMOS Technology A Research/Educational Proposal

In the past two decades, sigma-delta ( Σ∆ ) analog-to-digital converters are well suited for and widely used in instrumentation, voice and audio applications, featuring low-frequency and high-resolution. The reason behind this is because high resolution of sigma-delta ( Σ∆ ) architecture is obtained through trading off speed of modern CMOS (or BiCMOS) technology for high accuracy. With the continuing scale down of CMOS technology feature size and ever increasing operation speed, as well as architectural advances, Σ∆ A/D converters could work at higher frequencies up to several hundred to few Ms/s Nyquist rate. The large market need for wireless and internet applications are main and overwhelming drive for the research and development of higher speed Σ∆ A/D converters. The bandwidth and resolution requirements of some sample communication applications are shown in Table I.