| 摘要 |
<p>The present invention provides a method and apparatus for qualifying data peaks in a raw data signal produced by a magnetic transducer. According to the invention the apparatus comprises:- at least three comparators (122-134), each connected to a one of at least three corresponding data latches (136-146) and a one of at least three threshold reference levels (VH, VM, VL), comprising a high-level, a medium-level and a low-level threshold level, for comparing the raw data signal with the threshold reference levels to produce a latched output representing the raw data signal; means for detecting peaks in the raw data signal; and logic means (148, 150), including means for detecting the polarity cycle in the raw data signal, connected to the data latches (136-146) for selecting the first highest peak occurring in the raw data signal during a polarity cycle, said logic means including a phase lock loop to which only signals indicative of the raw data signal exceeding the medium-threshold level are input. <IMAGE></p> |
