Signaling method and apparatus for write assist of high coercivity media using integrated half coil
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United States of America Patent
Stats
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Jan 28, 2014
Grant Date -
Apr 21, 2011
app pub date -
Oct 16, 2009
filing date -
Oct 16, 2009
priority date (Note) -
In Force
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Abstract
A signaling method and apparatus for providing two write assist components for perpendicular thin film heads writing to high coercivity media is disclosed. The two components provided by the present invention include a media writing assist component and a head switching assist component. Circuit wiring configurations and waveforms for driving an auxiliary half coil are disclosed. These include configurations for connecting the auxiliary half coil in parallel with the main data coil, or connecting the auxiliary half coil to the thermal flight control system. Provision for both common mode signals as well as differential mode signals are disclosed. RF sinusoidal waveforms between 1 and 5 GHz have been found suitable for head switching assist functions for either symmetric current feed and common mode current configuration, or asymmetric current feed and differential mode current configuration. RF sinusoidal waveforms between 10 and 50 GHz have been found suitable for media writing assist functions for either asymmetric or symmetric current feed and differential mode configuration. Data derived signals obtained by passing the data pulse train though high pass filtration has been found to provide both head switching assist and media writing assist functionality. Data derived signals can be used with or without the RF signals.

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Patent Owner(s)
Patent Owner | Address | |
---|---|---|
WESTERN DIGITAL TECHNOLOGIES INC | 5601 GREAT OAKS PARKWAY SAN JOSE CA 95119 |
International Classification(s)
Inventor(s)
Inventor Name | Address | # of filed Patents | Total Citations |
---|---|---|---|
Franca-Neto, Luiz M | Sunnyvale, US | 100 | 1018 |
Knigge, Bernhard E | San Jose, US | 52 | 1082 |
Van, Der Heijden Petrus Antonius | San Jose, US | 58 | 548 |
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