13189402

Paragraph Number

279

Using equation 1, for example, if there are twenty-four channels 606a-n (η=24), eight possible read voltage threshold settings for each channel 606 (λ=8), and only two of the twenty-four channels 606a-n have read voltage thresholds that need to be adjusted (x=2), there are 17,644 total different combinations of read voltage threshold settings. If the number of channels 606 with read voltage thresholds that need adjusting increases to three, the number of different combinations increases to 1,036,288. The configuration module 352 drastically reduces these numbers by detecting which channels 606a-n have read voltage thresholds that need adjusting. In addition, comparing the known bias of the data on the media in a storage grouping to the current bias indicates the direction to adjust the read voltage thresholds. Knowing the direction in which to adjust the read voltage threshold greatly reduces the search space for a suitable voltage in the channels known to have a data error.

Added by DJM 3 2021