Incorporating Comparative TDR into the Device Analysis Flow

Time domain reflectometry (TDR) is widely used to measure the electrical length of conductors. It has also proven useful for isolating failures in ICs. This article describes a variation of the method, called comparative TDR, that overcomes inherent timing limitations and simplifies use. It discusses the basic hardware requirements of the new technique and presents examples demonstrating its use on opens and shorts in ceramic flip-chip packages.