Systems and methods for filter based media defect detection

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Fig. 4

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203

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500 501 7’ Write Data Read Data <— 576 Read/Write 503 Head Read Channel including Media 0 E Interface Defect Detection P Controller > Using Filter ‘ I r5e?(;np E Based DGTGCII — Platter Detection Q VCM Spindle Motor —> E Hard Disk Motor Controller H Controller 566 @ Fig. 6 _ 600 Transmitter r_/ m \ Transfer Medium E Receiver Including Media Defect Detection Using Filter Based Defect Detection Fig. 7

E

700

Receive Data Signal E Filter Data Signal <Y HP Filter Mode? E M I N V Determine Absolute Value of the Data 8' l fie Filter the Absolute Value of the Data Signal E Filtered Data Y Signal > Threshold? @ Defect Indication Dlrlcrgmentt N sserted for Minimum period aite a a oun er 4' Threshold 74_5 Exceeded? Y N 1 Reset Data Counter E F|g' 8 Set Defect Indicator E >|