Abstract: In one embodiment a control unit of a communication system exchanging a multiple-phase time-interleaved data includes a first Phase-Locked Loop (PLL) to generate a set of un-calibrated multiple-phase signals of a first-clock; a second-PLL, a pulse generator, a pulse-width measurement unit and a phase calibration engine to evaluate adjustments required in a temporal location of a logically critical voltage transition edge in each signal in the un-calibrated set; and a phase adjustment unit to adjust the temporal location of the logically critical voltage transition edge in each signal in the un-calibrated set to generate a set of calibrated multiple-phase signals of the first-clock such that each signal in the calibrated set includes the logically critical voltage transition edge which is time skewed in a predetermined amount from the logically critical voltage transition edge in other signals in the same set within a predetermined accuracy.

Abstract: A method, apparatus and/or system of a duty cycle counting phase calibration scheme of an I/O interface is disclosed.