Differential signals are used in a wide variety of applications, including high-speed serial data devices and many components such as amplifiers, mixers, filters, and PCBs. The advantages are many, including noise immunity, reduced power consumption and less crosstalk, but differential devices often also require special test methods.

This white paper discusses the theory of the true differential versus virtual differential measurement method and the impact on accuracy when evaluating the performance of differential devices. A measurement example is also shown comparing the two methods.