Western Digital Technologies, Inc.

Western Digital (Fremont), Inc.

William Don Huber

Tzong-Shii Pan

Michael L Mallary

Yih-Jen Dennis Chen

Yiduo Zhang

Jack M Chue

Yiao-Tee Hsia

Jon Jacoby

Tomas D Hugunin

A disk drive read circuit is disclosed comprising a read element for generating a read signal, and a sense amplifier comprising an input terminal coupled through a first capacitor to the read element and an output terminal coupled through a second capacitor to a transmission line, wherein the sense amplifier is for amplifying the read signal.

Disk drive read circuit comprising an AC coupled sense amplifier for amplifying a read signal

A disk drive includes a write head that includes a slider, a write transducer disposed on the slider, and a laser device affixed to the slider. The write transducer is driven by a first electrical signal that is carried on at least one of a plurality of conductive traces of a laminated flexure to which the write head is attached. The laser device is driven by a second electrical signal that is also carried by the same at least one of the plurality of conductive traces. The first signal is characterized by a first frequency, and the second electrical signal is characterized by a second frequency that is different from the first frequency.

Energy-assisted magnetic recording device having laser driving signal and magnetic write signal sharing same electrical conductor

A disk drive suspension assembly has a load beam and a laminated flexure attached to the load beam. The laminated flexure includes a structural layer with a head mounting tongue, and first and second conductive layers. A first dielectric layer is disposed between the structural layer and the first conductive layer, and a second dielectric layer is disposed between the first conductive layer and the second conductive layer. The first conductive layer includes a first plurality of interleaved traces with at least a first conductive trace and a second conductive trace separated by a first lateral intertrace spacing. The second conductive layer includes a second plurality of interleaved traces with at least a third conductive trace and a fourth conductive trace separated by a second lateral intertrace spacing. The fourth conductive trace overlies the first lateral intertrace spacing and the first conductive trace underlies the second lateral intertrace spacing.

Disk drive suspension assembly with flexure having dual conductive layers with staggered traces

A solderless compression connector is disclosed operable to couple first and second electrical components. The solderless compression connector comprises a housing comprising a dielectric forming a plurality of chambers, and an elongated conducting element disposed in each chamber. Each elongated conducting element comprises a first end operable to engage a first electrical lead of the first electrical component, and a second end operable to engage a second electrical lead of the second electrical component. Each elongated conducting element comprises a substantially constant thickness, and each elongated conducting element comprises a substantially constant width along a length of the elongated conducting element. A spacing between at least two of the elongated conducting elements is substantially constant. After installing the solderless compression connector, the elongated conducting elements are housed substantially within the respective chambers.

Solderless compression connector comprising constant width conducting elements housed substantially within a dielectric when installed

A disk drive is disclosed comprising a plurality of disk surfaces, and a plurality of heads actuated over the respective disk surfaces. In one embodiment, control circuitry generates a pulse duty cycle signal for one of the heads. In another embodiment, the control circuitry generates a first pulse width modulated signal for a first head, and a second pulse width modulated signal for a second head, wherein the second pulse width modulated signal comprises a phase offset from the first pulse width modulated signal.

Disk drive employing pulse width modulation of head control signal

A disk drive is disclosed comprising a disk, a head actuated over the disk, a preamp, and an interconnect for coupling the head to the preamp. The interconnect comprises a first transmission line stacked with a second transmission line, and a dielectric between the first transmission line and second transmission line. The transmission lines form an approximation of at least one inductor/capacitor ladder network and an approximation of at least one inductor/capacitor lattice network. The lattice network comprises a first leg and a second leg, and a cross-over hub for interconnecting the first leg and the second leg.

Disk drive comprising an interconnect with transmission lines forming an approximated lattice network

A disk drive comprising a disk, and a head actuated over the disk, the head comprising a read element and a write element. The disk drive further comprises a preamp and an interconnect comprising a first transmission line and a second transmission line coupling the head to the preamp. A compensation network is disclosed operable to compensate for an impedance discontinuity in the first and second transmission lines, the compensation network comprising a first trace and a second trace connected in parallel with the first and second transmission lines, wherein a shape of the first and second traces varies to form at least a first capacitor.

Disk drive comprising impedance discontinuity compensation for interconnect transmission lines

A disk drive is disclosed comprising a disk, a head actuated over the disk, a preamp, and an interconnect for coupling the head to the preamp. The interconnect comprises a first transmission line stacked over a second transmission line, and a dielectric between the first transmission line and second transmission line. A shape of the first and second transmission lines varies along a length of the interconnect such that the interconnect comprises an approximation of an inductor/capacitor ladder network.

Disk drive comprising stacked and stepped traces for improved transmission line performance

A method and system for providing an energy assisted magnetic recording (EAMR) disk drive are described. The disk drive includes a magnetic recording media, a pre-amplifier, an EAMR head, and at least one clock recovery circuit. The pre-amplifier provides a write current signal and a write gate signal for providing power to the EAMR head. The EAMR head includes at least one write transducer and at least one laser. The write transducer(s) are coupled with the pre-amplifier and include at least one writer coil. The write current signal from the pre-amplifier drives the writer coil(s). The clock recovery circuit(s) are coupled with the laser(s). The clock recovery circuit(s) receive the write current signal and the write gate signal and output laser control signal(s) that energize the laser(s) such that the laser(s) are energized synchronously with the writer coil(s).

Method and system for pulsing EAMR disk drives

Disclosed herein are embodiments directed to a head gimbal assembly including a novel suspension assembly that includes a flexure tail with a first plurality of apertures in its structural layer. Each of the first plurality of apertures underlies a first trace but not a second trace. Each of a second plurality of apertures in the structural layer underlies a second trace but not the first trace. Each of the first plurality of apertures includes a corresponding region of maximum width, and each of the second plurality of apertures includes a corresponding region of maximum width, as measured in the width direction. None of the corresponding regions of maximum width of the first plurality of apertures is disposed in an overlapping position along the long axis as any of the corresponding regions of maximum width of the second plurality of apertures.

Suspension assembly including a flexure tail with staggered rows of apertures

A novel suspension assembly includes a flexure tail with a first plurality of apertures in its structural layer. Each of the first plurality of apertures underlies a first trace but not a second trace. Each of a second plurality of apertures in the structural layer underlies a second trace but not the first trace. Each of the first plurality of apertures includes a corresponding region of maximum width, and each of the second plurality of apertures includes a corresponding region of maximum width, as measured in the width direction. None of the corresponding regions of maximum width of the first plurality of apertures is disposed in an overlapping position along the long axis as any of the corresponding regions of maximum width of the second plurality of apertures.

A disk drive is disclosed comprising a disk, a head actuated over the disk, and control circuitry operable to estimate a fly height of the head by tuning a phase locked loop (PLL) in response to a fly height capacitance. In one embodiment, the PLL comprises a resistive component having a second terminal coupled to the fly height capacitance, a variable oscillator operable to generate a first oscillating signal applied to a first terminal of the resistive component to generate a second oscillating signal at the second end of the resistive component, and a phase detector operable to generate a control signal by comparing a phase of the first oscillating signal to a phase of the second oscillating signal. The control signal is applied to the variable oscillator to adjust a frequency of the first oscillating signal.

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Hollister, CA, United States of America

William Don Huber