Transmission Line Pulse curve tracer is a test method used to plot the I-V (current-voltage) characteristics of an ESD Protection device. A fast square wave pulse is applied to the pin under test. At the end of the pulse, the voltage and current are measured. Subsequent pulses have increased voltage and/or current. The resulting voltage and current measurements can then be plotted as an I-V curve. The pin under test leakage can also be monitored after each pulse, thereby identifying the onset of failure. The MEFAS test setup uses a 90 nanosecond pulse. The maximum current is 3 amps. The maximum voltage is 250 volts. The high currents are possible because the pulse is too fast to allow significant heating.

Example Snap-back curve: