The tests aim at identifying and compensate process variation or fabrication issue. If a compensation is not possible, then it is important to identify and discard failing devices as soon as possible not to waste time (and consequently money) on useless devices. The tests especially suffer from voltage droops when it is performed at critical voltages values. It is crucial to mitigate this voltage droops that can cause false fails during the test of the DUTs. This is especially true if the amplitude of the droop is enough to bring the power supply below what is called the Vfail voltage, overcoming the guard band set by the manufacturer Fig.