A 10MHz continuous time bandpass delta sigma modulator

Abstract

This paper presents a continuous-time bandpass delta-sigma modulator using two integrators as a resonator. In the proposed approach, cross-coupled differential pairs are used as subtractors to provide good isolation between input and feedback signals. The delta-sigma modulator is designed for a 10 MHz signal frequency with a 40 MHz sampling frequency. A prototype integrated circuit was fabricated using 0.5 micron CMOS technology.