Abstract: A storage system includes a magnetic write head, a magnetic storage medium, a write data circuit having a write data output and a magnet length signal output, and a preamplifier that receives the write data and a magnet length signal from the write data circuit, and sets at least one write current characteristic through the magnetic write head based at least in part on the magnet length signal. The write data circuit processes write data to be recorded on the magnetic storage medium by the magnetic write head. The magnet length signal output communicates magnet lengths in the write data.

Abstract: A storage system includes a magnetic storage medium, a magnetic write head, a channel circuit and a preamplifier. The channel circuit includes a write data input, a differentiated edge emphasis signal generator, a write data output and a differentiated edge emphasis signal output. The preamplifier includes a write data input configured to receive write data from the channel circuit write data output, an edge emphasis signal input configured to receive a differentiated edge emphasis signal from the channel circuit differentiated edge emphasis signal output, and a write current edge emphasis controller configured to generate a write current to the magnetic write head based at least in part on the write data and on the differentiated edge emphasis signal.

Abstract: A storage system includes a magnetic write head, a magnetic storage medium, a channel circuit comprising a write data output, wherein the channel circuit is operable to process write data to be recorded on the magnetic storage medium by the magnetic write head, and a preamplifier operable to receive the write data from the channel circuit, wherein the preamplifier comprises a number of register pages configured to store pattern dependent write current characteristics for a variety of magnet lengths, and wherein the preamplifier is operable to retrieve the write current characteristics based on magnet lengths and to record data bits on the magnetic storage medium using the write current characteristics.

Abstract: A storage system includes a magnetic write head, a magnetic storage medium, a channel circuit comprising a write data output, wherein the channel circuit is operable to process write data to be recorded on the magnetic storage medium by the magnetic write head, and a preamplifier operable to receive the write data from the channel circuit, wherein the preamplifier comprises a number of register pages configured to store pattern dependent write current characteristics for a variety of magnet lengths, and wherein the preamplifier is operable to retrieve the write current characteristics based on magnet lengths and to record data bits on the magnetic storage medium using the write current characteristics.

Abstract: A storage system includes a magnetic storage medium, a magnetic write head, a channel circuit and a preamplifier. The channel circuit includes a write data input, a differentiated edge emphasis signal generator, a write data output and a differentiated edge emphasis signal output. The preamplifier includes a write data input configured to receive write data from the channel circuit write data output, an edge emphasis signal input configured to receive a differentiated edge emphasis signal from the channel circuit differentiated edge emphasis signal output, and a write current edge emphasis controller configured to generate a write current to the magnetic write head based at least in part on the write data and on the differentiated edge emphasis signal.

Abstract: A storage system includes a magnetic write head, a magnetic storage medium, a write data circuit having a write data output and a magnet length signal output, and a preamplifier that receives the write data and a magnet length signal from the write data circuit, and sets at least one write current characteristic through the magnetic write head based at least in part on the magnet length signal. The write data circuit processes write data to be recorded on the magnetic storage medium by the magnetic write head. The magnet length signal output communicates magnet lengths in the write data.

Abstract: The present inventions are related to systems and methods for data processing, and more particularly to systems and methods for synchronizing operations in a data storage system.

Abstract: A system and method for power management in a hard disk drive (HDD) assembly incorporating two or more read sensors includes directing a read/write head to follow a track; depowering one or more read sensors and readpath circuits associated with the read sensors; reading an analog readback signal through the first read sensor; processing the signal through an analog front-end to generate an input signal; sampling the input signal through an analog to digital converter at a first frequency to generate a first sampling signal; sampling the input signal through a second analog to digital converter at a second frequency to generate a second sampling signal; and generating a digital output signal from either or both sampling signals at a third sampling frequency through a digital signal processor. The method may additionally comprise adjusting a sampling frequency when power level reaches a threshold.

Abstract: Various embodiments of the present invention provide systems and methods related to pattern detection. As an example, a system for sample selection is disclosed that includes a difference calculation circuit, a comparator circuit, and an output selector circuit. The difference calculation circuit is operable to calculate a first difference between a first value corresponding to a first digital sample and a second value corresponding to a second digital sample, and to calculate a second difference between a third value corresponding to a third digital sample and a fourth value corresponding to a fourth digital sample. The comparator circuit is operable to compare the first difference with the second difference to yield a comparison output. The output selector circuit is operable to select one of the second value and the fourth value as an output based at least upon the comparison output.

Abstract: Various embodiments of the present invention provide systems and methods related to pattern detection. As an example, a system for sample selection is disclosed that includes a difference calculation circuit, a comparator circuit, and an output selector circuit. The difference calculation circuit is operable to calculate a first difference between a first value corresponding to a first digital sample and a second value corresponding to a second digital sample, and to calculate a second difference between a third value corresponding to a third digital sample and a fourth value corresponding to a fourth digital sample. The comparator circuit is operable to compare the first difference with the second difference to yield a comparison output. The output selector circuit is operable to select one of the second value and the fourth value as an output based at least upon the comparison output.

Abstract: A circuit generally comprising a first circuit and a phase lock loop. The first circuit may be configured to (i) collect a plurality of samples per cycle during a plurality of cycles of an input signal and (ii) calculate a phase offset and a frequency offset for the input signal relative to a clock signal in response to the samples. The phase lock loop may be configured to (i) preset a phase error signal to the phase offset and a frequency error signal to the frequency offset and (ii) generate the clock signal in response to the phase error signal and the frequency error signal.

Abstract: A method and apparatus for write precompensation in a direct access storage device are provided. A data write encoder generates a data signal to be written. A write precompensation delay circuit is coupled to the data encoder for receiving and delaying the data signal. The write precompensation delay circuit includes a first delay path and a second delay path in parallel with the first delay path. The first delay path and the second delay path have different delay values. In one arrangement, both the first delay path and the second delay path include a plurality of delay cells connected together in a chain. The delay cells of the first delay path have a first predetermined delay value and the delay cells of the second delay path have a second predetermined delay value. A ratio of the second predetermined delay value to the first predetermined value is set equal to one of approximately 3/2, 4/3, 5/4, 6/5, or 7/6.