Dynamic magnetic information storage or retrieval – General processing of a digital signal – Head amplifier circuit
Reexamination Certificate
2007-06-05
2007-06-05
Nguyen, Khai M. (Department: 2819)
Dynamic magnetic information storage or retrieval
General processing of a digital signal
Head amplifier circuit
C360S025000, C360S031000, C360S032000, C360S067000, C341S118000, C341S139000
Reexamination Certificate
active
11338518
ABSTRACT:
To calibrate the VGA of a read head, test signals from a DAC are input to the VGA and the output of the VGA is observed, with the gain of the VGA being adjusted as appropriate. So that the DAC need not be made with tight tolerances, a DC signal can be fed into the DAC prior to VGA calibration, and an auxiliary ADC is used to receive the output of the DAC and to determine, for a given DC input, what the signal produced by the DAC actually is. In this way, during subsequent VGA calibration the test signal from the DAC is known not by virtue of the DAC having a tight manufacturing tolerance but by virtue of the actual measurements of its outputs for given register inputs.
REFERENCES:
patent: 4635142 (1987-01-01), Haugland
patent: 4750058 (1988-06-01), Hirt et al.
patent: 5375145 (1994-12-01), Abbott et al.
patent: 5442492 (1995-08-01), Cunningham et al.
patent: 5576906 (1996-11-01), Fisher et al.
patent: 5737342 (1998-04-01), Ziperovich
patent: 6078444 (2000-06-01), Vishakhadatta et al.
patent: 6429988 (2002-08-01), Bhaumik et al.
patent: 6441983 (2002-08-01), Philpott et al.
patent: 6519103 (2003-02-01), Cyrusian
patent: 6628467 (2003-09-01), Cyrusian
patent: 6661590 (2003-12-01), Cyrusian et al.
patent: 6671112 (2003-12-01), Murakami et al.
patent: 7027245 (2006-04-01), Mitchell et al.
patent: 7057835 (2006-06-01), Chan et al.
patent: 2005/0213238 (2005-09-01), Mitchell
patent: 2005/0243456 (2005-11-01), Mitchell
Mary McCarthy, “Peak-to-Peak Resolution Versus Effective Resolution,” Analog Devices, Application Note, AN-615, Jul. 11, 2003, pp. 1-2. www.analong.com.
“DC Characterization of an ADC,” Pre-Lab, ENTC 351 Lab 7, 1999, http://ee.tamu.edu/inseok/entc351/prelab7—1999.pdf, no month.
Curtis Michael William
Nasu Koji
Pipal Vicki Lynn
Richetta Raymond Alan
Hitachi Global Storage Technologies - Netherlands B.V.
Nguyen Khai M.
Renesas Technology Corporation
Rogitz John L.
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