Method and apparatus for measuring duty cycle based on data eye monitor

摘要

Methods and apparatus are provided for measuring the duty cycle of a signal based on a data eye monitor. The duty cycle of a signal is estimated by sampling the signal for a plurality of different phases and evaluating the samples to identify when the signal crosses a predefined amplitude value. The duty cycle is estimated based on a statistical variation between the points of predefined amplitude crossing, such as points of zero crossing. The duty cycle can optionally be corrected based on the measured duty cycle value. The sampling of the signal may be performed, for example, using one or more latches.