Patent ID: 7869544
Filing Date: 2011-01-11
Classification: H04L

Abstract:
1. An integrated circuit operable to determine an eyewidth of a data signal, comprising an electronic circuit operable to: a) recover a phase of a clock from a data signal for use as a first phase of a sampling clock; b) in accordance with a phase control signal having a number M of pulses, shift the phase of the sampling clock away from the first phase by a number N multiplied by a predetermined phase amount, the number N being proportional to the number M of pulses of the phase control signal; c) sample the data signal with the shifted sampling clock phase to obtain sample data; d) determine whether the sample data contains error; e) when the sample data does not contain error, recover the phase of the clock from the data signal again for use as the first phase of the sampling clock, increase the number M and repeat steps (b) through (e); and f) when the sample data contains error, determine the eyewidth based on the last shifted phase of the sampling clock prior to determining that the sample data contains error.