Testing a power supply for line and load transients

Line and load transients are step functions that inject disturbances into the power supply. A load transient injects disturbance into the output by stepping the load current, and a line transient does so by stepping the line voltage. The supply’s output response demonstrates its ability to attenuate the various frequency components of a line or load step. The following discussion describes these tests and the information they provide about a power supply.