Dynamic magnetic information storage or retrieval – General processing of a digital signal – Head amplifier circuit
Reexamination Certificate
2006-02-28
2006-02-28
Hudspeth, David (Department: 2651)
Dynamic magnetic information storage or retrieval
General processing of a digital signal
Head amplifier circuit
Reexamination Certificate
active
07006313
ABSTRACT:
A write driver100, 200, 300is implemented to provide near-ground common mode output voltages to produce a more symmetrical head voltage swing (i.e. ±0.4V from ground to ±5V supply voltages). These features help to reduce the effects of common mode impedance associated with the interconnection to the disk drive head to improve overall performance. Lower jitter at high data rates can be achieved when compared to prior art techniques for implementing current mode write drivers. Further, the matched impedance between the write driver100and the interconnection106eliminates unwanted reflections. ECL level voltage swings (200–500 mV) have replaced more conventional CMOS level voltage swings (5V) to further reduce overall power dissipation associated with the write driver. The small ECL level switching further maintains constant power dissipation with changes in operating frequency and results in less NTLS effects due to quieter supplies.
REFERENCES:
patent: 4879610 (1989-11-01), Jove et al.
patent: 4964107 (1990-10-01), Galbraith et al.
patent: 5079448 (1992-01-01), Matsumoto
patent: 5293278 (1994-03-01), Pahr
patent: 5296975 (1994-03-01), Contreras et al.
patent: 5386328 (1995-01-01), Chiou et al.
patent: 5668676 (1997-09-01), Voorman et al.
patent: 5790336 (1998-08-01), Voorman et al.
patent: 5834965 (1998-11-01), LeClerc
patent: 5841603 (1998-11-01), Ramalho et al.
patent: 5896248 (1999-04-01), Hanrahan et al.
patent: 6236247 (2001-05-01), Ngo
patent: 6246533 (2001-06-01), Davis et al.
patent: 6356113 (2002-03-01), Contreras et al.
patent: 6512646 (2003-01-01), Leighton et al.
patent: 6545514 (2003-04-01), Barrow
patent: WO98/ 10420 (1998-03-01), None
patent: WO99/ 60562 (1999-11-01), None
patent: WO 00/79521 (2000-12-01), None
Article: “A 1Gb/s Read/Write—Preamble for Hard-Disk Drive Applications” 2001 IEEE International Solid-State Circuits Conference, Session 12, Signal Processing for Storage and Coding, pp. 150-151, 188-189 (Hugo Veenstra; Jan Mulder; Luan Le; Giuseppe Grillo).
Brady W. James
Hudspeth David
Rodriguez Glenda P.
Swayze, Jr. W. Daniel
Telecky , Jr. Frederick J.
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