An auto-tuning structure for continuous time sigma-delta AD converter and high precision filters

In this paper, a discrete auto-tuning structure is proposed for continuous time sigma-delta AD converter (ADC) and applications that require high linearity, moderate precision in RC or C/g/sub m/ time constant. Comparison with continuous gm tuning and some other passive tuning implementations is also presented. A circuit is designed in 0.5 /spl mu/m CMOS process to examine the performance of the proposed circuit structure.