Infrared emission microscopy (IREM) is often the simplest and fastest fault isolation technique. In contrast to emission microscopy, laser-based techniques, such as thermally induced voltage alteration and light induced voltage alteration (LIVA), are not as dependent on leakage or the specific voltage of the defect to provide localization but are able to observe variations in the defective current drawn by the defect. This paper describes a method of applying LIVA to synthesized logic connected to large-scale power plane by controlling the amount of decoupling capacitance on the power supply. This has proven to provide very useful fault isolation beyond what is possible with emission microscopy. The logic LIVA result allowed the determination of locations of the two emissions seen in the IREM image as well as the word-line driver. This result provides a complete picture of the failure exact word-line driver-simplified physical failure analysis.