The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 2000
Filed:
Apr. 01, 1998
Robert B Staszewski, Garland, TX (US);
Gennady Feygin, Dallas, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A read channel circuit (27) for a hard disk drive system (10) includes an analog-to-digital converter (38) having an output (39) which is supplied through a filter (41) to a detector (46) and to a band/error circuit (47). The band/error circuit extracts from the filter output a band value (48) and an error value (49). The band and error values are used by a timing recovery loop (51, 53) to control the operation of the analog-to-digital converter, and are used by a gain recovery loop (51, 54) to facilitate an automatic gain control function for an analog circuit (36). The band/error circuit uses targets and thresholds which are each a power of two, so that a predetermined number of the least significant bits from the output of the filter can be used as the error value, without modification. The band value is determined from the most significant bits of the output of the filter. The filter not only shapes the signal spectrum, but also performs an integer space transformation that normalizes the output of the analog-to-digital converter with respect to the predetermined targets and thresholds of the band/error circuit.