A Performance Comparison of CMOS Voltage-Controlled Ring Oscillators for its Application to Generation and Distribution Clock Networks

Abstract

In this work, a performance comparison of expanded CMOS voltage-controlled ring oscillators for non-resonant local clock generation and distribution networks is presented. Several differential and single-ended ring oscillators are designed and fabricated using long interconnection lines to achieve wide coverage chip. A test chip containing the several oscillators was fabricated using an Austria Microsystems (AMS) 0.35 µm CMOS technology. Experimental results show that it is possible to generate and distribute high frequency signals (GHz range) on a relativity large area (coverage) and low phase noise using non-resonant ring oscillators. This represents an attractive alternative for the design and implementation of local Clock Generation and Distribution Networks for systems on chip.