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Disk drive with channel and preamp with dynamic write-current control for write head

A technology for writing drives and disk drives, applied in the modification of read/write signals, configuration/installation of instruments, recording heads, etc., which can solve the problems of adjusting double bits and being unusable

Inactive Publication Date: 2017-02-01
HITACHI GLOBAL STORAGE TECH NETHERLANDS BV
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this look-back strategy cannot be used, for example, to adjust the first transition within a dibit or the overshoot current ahead of the first transition of a long magnet, both of which have historically been problematic

Method used

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  • Disk drive with channel and preamp with dynamic write-current control for write head
  • Disk drive with channel and preamp with dynamic write-current control for write head
  • Disk drive with channel and preamp with dynamic write-current control for write head

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Embodiment Construction

[0022] image 3 is a block diagram showing selected components in a disc drive with channel preplay dynamic waveform (CP-DWS) system according to the first embodiment of the present invention. Components in an embodiment reside in channel 31A and write driver preamp 18A. The write data stream input into channel 31A is initially processed by write data processing block 36 to detect data patterns for overshoot amplitude adjustment. Block 36 generates a corresponding overshoot amplitude signal, which drives an amplitude level modulation (AML MOD) unit 33 , which in turn drives write buffer 32 . The data stream output signal from write buffer 32 entering write driver preamplifier 18A is a differential signal including amplitude modulation.

[0023] The channels are modulated using AML to assign a predetermined specified overshoot to each bit sequence. Data patterns and corresponding overshoot magnitudes can be determined experimentally for a particular disk drive. AML modulati...

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Abstract

Disk drives with a channel system and write driver preamp architecture that dynamically adjusts the write driver's signal wave-shape depending on the write data signal pattern are described. The wave-shape control signal is generated in the channel and transmitted to the write driver preamp. Embodiments of the invention provide discrete n-level overshoot amplitude control using amplitude-level modulated (AML) signal. One embodiment implements a look-ahead strategy overshoot amplitude control where the overshoot amplitude for each transition depends only on the subsequent (following) bits in the data stream and not on any previously recorded data.

Description

technical field [0001] Embodiments of the invention relate generally to methods and apparatus used in magnetic data storage systems having rotating disks, and more particularly to generating signals for driving inductive write heads used in such systems. Background technique [0002] Prior art disk drive 10 (see figure 1 ) typically includes a main integrated circuit, typically called a system-on-chip (SOC) 11 , which contains a lot of electronics and firmware for the drive including the read / write channel system 31 . Each disk (not shown) can have thin film magnetic material on each of the planar surfaces. Each disk surface typically has a dedicated pair of read and write heads housed in a slider 13 that also includes a fly height control assembly. The slider is mechanically mounted on an actuator (not shown) with various flexible components to allow for an appropriate degree of movement during operation. Each slider is a subassembly that typically includes a hover assem...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): G11B5/55
CPCG11B5/5526G11B5/02G11B5/09G11B20/10009G11B20/10018
Inventor J.孔特雷拉斯S.Y.加尔松W.M.汉森A.塔拉托林
Owner HITACHI GLOBAL STORAGE TECH NETHERLANDS BV