Distributed digital ring oscillators in a digital system

摘要

A semiconductor device includes a system clock signal having a system clock period and a digital ring oscillator (DRO) cluster having DRO cells. Each of the DRO cells is disposed at a different location in the semiconductor device for producing a local ring oscillator clock signal. The local ring oscillator clock signal has a ring oscillator clock period that is shorter than the system clock period. The DRO cluster is configured to measure respective ring oscillator clock count in each of the DRO cells during a time window synchronized to the system clock.