In one embodiment, a plurality of signals are sequentially driven onto a signal path. Each of the signals has a pulsewidth defined by a trigger edge and a sensor edge, and at least some of the signals having different pulsewidths. After driving each signal, the signal is sampled at or about a timing of the signal's sensor edge to thereby characterize the signal's sensor edge. The sensor edge characterizations corresponding to the different signals are then analyzed to quantify a timing error induced by an impedance variation of the signal path.