sampling phase and slicing level of sampler c can be determined please referring to fig5 input data di passes through either linear or limiting amplifiers five samplers are presented sampler t sampler c and sampler b form a group to determine the slicing level sampler e sampler c and sampler l collaborate with each other to explore timing margin outputs of the three samplers in a group case a majority vote error is observed comparing the vote with the individual result two groups communicate with each other if necessary the clock from the clock and data recovery loop is divided down n times to save the power and area of the samplers and the following circuitry clock and data recovery loop can possibly merge with the samplers in one embodiment as in fig6 a if ase is the major hindering factor of the system performance the slicing level threshold of sampler c might simply be the average of that of sampler t and sampler b on the other hand if the waveform is severely distorted it would set the slicing level of sampler c such that u03b4t is maximal fig6 b demonstrates the locations of the samplers on the eye furthermore in another embodiment it is possible.