Class / Patent application number | Description | Number of patent applications / Date published |
360046000 | Head amplifier circuit | 68 |
20080204914 | Low Power Write Driver for a Magnetic Disk Drive - A write driver ( | 08-28-2008 |
20080253012 | MAGNETIC TAPE READ CHANNEL SIGNAL VALUES DEVELOPED EMPLOYING INTERMEDIATE BITS OF THE PATH MEMORY OF A PRML VITERBI DETECTOR - Magnetic tape read channel signal values are developed employing intermediate bits of the path memory of a PRML Viterbi detector. Identification logic identifies a most likely path memory state of the PRML Viterbi detector from the path metrics of the PRML Viterbi detector. An intermediate bit sequence of the identified most likely path memory state is obtained, the intermediate bit sequence extending from an initiation point of the path memory which is intermediate the output and the input of the PRML Viterbi detector. A sample value is determined which corresponds to the obtained intermediate bit sequence. | 10-16-2008 |
20080278838 | Thermal asperity detector and methods for use therewith - A thermal asperity detector for use in a hard disk drive includes a magnitude detector that produces a magnitude signal from a read head signal. A filter module filters the magnitude signal to produce a amplitude signal. A comparator compares the amplitude signal to an amplitude thermal asperity threshold and that generates thermal asperity data when the amplitude signal compares favorably to the thermal asperity threshold. | 11-13-2008 |
20090021852 | Apparatus, signal-processing circuit and device for magnetic recording system - To effectively suppress a signal in a low frequency region in which the medium noise and the signal distortion are concentrated, and in order to effectively utilize a detected component of the reproduced signal in the low frequency region, a target of partial response equalization to the perpendicularly recorded/reproduced signal is set so that the low-frequency component around the direct current is suppressed to a regulated quantity for both the effective suppression and the effective utilization. Accordingly, a maximum-likelihood decoding process is carried out through the target of partial response equalization. Reliability of data detection is made higher and a signal-to-noise ratio is improved, so that the noise from the recording medium can be reduced more and it is possible to provide a high-density magnetic recording/reproducing apparatus. | 01-22-2009 |
20090122434 | HEAD IC, READ CIRCUIT AND MEDIA STORAGE DEVICE - A head IC, which adjusts an amplitude level of a read signal of a head, for outputting to a read channel having an AGC amplifier, includes: a differential amplifier; an AGC circuit; external gain setting sections; and a switch. Since the AGC amplifier is disposed in the head IC, the amplitude from the head is automatically adjusted in the head IC, and the signal level, which enters the input dynamic range of the AGC amplifier of the read channel, can be adjusted. The AGC amplifier can be operated as a fixed gain amplifier using a gain value which is set from the outside, so the power consumption can be minimized even if automatic adjustment is performed. | 05-14-2009 |
20090141386 | HEAD IC, READ CIRCUIT AND MEDIA STORAGE DEVICE - A head IC adjusts an amplitude level of a read signal of a head and outputs to a read channel having an AGC amplifier, includes an AGC amplifier. The AGC amplifier has a feedback loop control type first amplifier and a feed-forward control type second amplifier. The precision of control with respect to a target value is improved, and an AGC amplifier with fast response can be configured. Further, increases in the AGC pull-in type can be prevented, stability can be assured, and erroneous AGC judgments can be prevented. | 06-04-2009 |
20090244758 | Hard Disk Drive Preamplifier Timers and Methods to Calibrate Hard Disk Drive Preamplifier Timers - Hard disk drive preamplifier timers and methods to calibrate hard disk drive preamplifier timers are disclosed. A timer is in a hard disk drive preamplifier comprises a first switch to selectively store charge in a storage device based on an input signal, the storage device receiving a first current and storing the charge to cause the storage device to have a first voltage that increases at a first rate; a compensation device to cause the first voltage to be substantially equal to a second voltage after a predetermined time period; and a trigger to output a signal when the first voltage is substantially equal to the second voltage, the predetermined time period controlling a transition time between a first hard disk drive operating condition and a second hard disk drive operating condition different than the first operating condition. | 10-01-2009 |
20100061005 | High speed digital signaling apparatus and method using reflected signals to increase total delivered current - A signaling apparatus and method are described that use reflected signals to increase the total current delivered to a receiver. Dynamic source-side transmission line termination control is employed to generate reflected signals that constructively add to a nonreflected signal to enhance the signal at the receiver. Switching controls selectively connect and disconnect the transmission line source-side termination resistors to either provide signal termination or remove it. Driver designs using either voltage or current sources for use in signaling systems (including, for example, magnetic storage devices with inductive coil based write heads) are described. | 03-11-2010 |
20100073798 | Systems and Methods for Compensating Baseline Wandering in Perpendicular Magnetic Recording - Various embodiments of the present invention provide systems and methods for reducing low frequency loss in a magnetic storage device. For example, a data processing circuit is disclosed that includes a digital filter that receives a series of digital samples and provides a filtered output. The filtered output is provided to a data detector that performs a data detection on the filtered output to create a detected output. A first summation element subtracts the filtered output from the detected output to create an error signal, and a second summation element subtracts the error signal from the filtered output to create a wander basis signal. A baseline correction feedback circuit receives the wander basis signal and provides a wander compensation signal. A derivative of the wander compensation signal is provided as feedback to the digital filter. | 03-25-2010 |
20100073799 | DETECTING CONTACT BETWEEN A SLIDER AND A DATA STORAGE MEDIUM WITHOUT A SEPERATE CONTACT-DETECTION VOLTAGE SOURCE - A circuit includes a slider, a data storage medium and a contact detection circuit electrically coupled to the slider and to the data storage medium. The contact detection circuit is configured to sense an electrical current indicative of contact between the slider and the data storage medium and responsively provide a contact detection output. The electrical current is produced without the application of a separate voltage between the slider and the data storage medium. | 03-25-2010 |
20100177423 | DUAL GAIN CONTROL FOR MAGNETIC DATA STORAGE SYSTEM - A system according to one embodiment includes an analog input for receiving an analog signal; a variable gain amplifier coupled to the analog input; a first gain control circuit coupled to the variable gain amplifier for controlling the gain of the analog signal; an analog to digital converter for converting the analog signal to a digital signal; a first gain error generation circuit for generating a first gain error signal based on an output of the analog to digital converter, the first gain error signal or derivative thereof being received by the first gain control circuit; and a second gain error generation circuit for generating a second gain error signal based on the digital signal, the second gain error signal or derivative thereof being received by the first gain control circuit, wherein the first gain control circuit uses at least one of the gain error signals to control the gain of the analog signals. | 07-15-2010 |
20100214683 | PRINTED CIRCUIT CABLE ASSEMBLY FOR A HARD DISK DRIVE - A printed circuit cable assembly (PCCA) for a hard disk drive (HDD) is disclosed. The PCCA includes a stiffener portion having an elongated shape that includes an integrated circuit (IC) chip. The PCCA also includes a flexible portion extending from the elongated stiffener portion, wherein the PCCA is configured to be mountable on a headstack of the HDD such that an entire footprint of the IC chip overlays a metallic portion of the headstack of the HDD. | 08-26-2010 |
20100265611 | CONTROLLER, DISK DRIVE HAVING THE CONTROLLER, AND DATA PROCESSING SYSTEM HAVING THE DISK DRIVE - A controller for use in a disk drive includes a comparison signal generator for comparing a period of time when a write unsafe signal output from a pre-amplifier is activated with a reference period of time to generate a comparison signal; a write failure signal generator for generating a write failure signal according to a write gate signal and the comparison signal; and a logger for logging at least one of the period of time when a write unsafe signal output from a pre-amplifier is activated and the number of times of activations of the comparison signal. | 10-21-2010 |
20110038071 | METHOD OF OPERATING PRE-AMPLIFIER, PRE-AMPLIFIER, AND APPARATUSES INCLUDING THE SAME - A method of operating a pre-amplifier of a hard disk drive is provided. The method includes generating a comparison signal corresponding to a result of comparing a reference signal with a difference between differential signals corresponding to write data, and controlling transmission of the differential signals to a write head in response to the comparison signal. | 02-17-2011 |
20110141603 | HEAD/DISK CONTACT DETERMINATION - A disk drive including a sensor element that senses contact between a head slider and a disk, a head integrated circuit (IC) comprising an amplification circuit section that amplifies a signal of the head slider, a controller IC comprising a controller that accesses a register of the head IC for controlling the head IC, and an identification section, within the head IC, that determines a contact frequency of the contact by the sensor element by using a timing control signal of the controller IC. | 06-16-2011 |
20110149425 | SYSTEM FOR MONITORING LSI SUPPLYING CURRENT TO LOAD - According to one embodiment, A system includes a first LSI, a second LSI, a controller and a current monitoring and determination module. The first LSI operates on a first power supply voltage generated by a first voltage regulator included in the second LSI. The module operates on a device power supply voltage supplied from the device power supply. The module monitors current flowing between the first LSI and the first voltage regulator, determines an abnormality in the first LSI on the basis of the current monitoring result and transmits an abnormality signal to the controller on the basis of the abnormality determination result. The controller operates on a second power supply voltage generated by a second voltage regulator included in the second LSI and reports an abnormality in the first LSI to a host system in accordance with the reception of the abnormality signal. | 06-23-2011 |
20110188145 | SERVO TRACK WRITER AND OPERATING METHOD - A method of operating a servo track writer includes writing a clock pattern signal to a magnetic recording medium of a head disk assembly, reading the clock pattern signal written to the magnetic recording medium and dividing a frequency of a read clock pattern signal, and supplying a clock pattern signal having a divided frequency to a spindle motor for rotating the magnetic recording medium. | 08-04-2011 |
20110188146 | IC PROTECTION CIRCUIT, METHOD FOR PROTECTING IC, AND APPARATUSES HAVING THE IC PROTECTION CIRCUIT - An electronic device includes a power supply line connected between a DC power supply and an integrated circuit, and a first electronic element and a second electronic element serially connected between the power supply line and ground. The second electronic element is open when the first electronic element is short-circuited due to an overvoltage induced in the power supply line. When the overvoltage exceeds a breakdown voltage of the first electronic element, the first electronic element supplies an overcurrent induced in the power supply line to the second electronic element. | 08-04-2011 |
20110188147 | METHOD ADJUSTING GAIN OF VARIABLE GAIN AMPLIFIER AND APPARATUS USING SAME - A method of adjusting gain of a variable gain amplifier of a read/write channel circuit includes loading a first VGA gain value that is read channel optimized, in a first register, loading a second VGA gain value that is adapted, in a second register, calculating a third VGA gain value according to a result of operation of the first VGA gain value and the second VGA gain value, and overwriting the third VGA gain value to the first register. | 08-04-2011 |
20110211271 | TRAPPING ELECTRON ASSISTED MAGNETIC RECORDING SYSTEM AND METHOD - A system and method for trapping electron assisted magnetic recording is disclosed. A magnetic recording system comprises a magnetic storage media, a read/write head, and a power supply for applying a negative DC electrical bias to the magnetic storage media in order to reduce the media switching field during the writing process. Recording is performed by applying an AC magnetic field produced by a write pole and a DC electrical field to assist in the writing. An embodiment of the invention uses a high electrical field to trap free electrons into an unfilled electronic shell of magnetic particles of the magnetic storage media, in particular, (3d) shell of transition elements, (4f) shell of rare earths of lanthanides series, and (5f) shell of actinides series. The trapped electron decreases anisotropy of magnetic particles due to reduced number of Bohr magnetron. As a result, a conventional head is able to write very high anisotropy magnetic storage media. | 09-01-2011 |
20110249357 | METHOD OF PROTECTING INFORMATION WRITTEN TO RECORDING MEDIUM, AND DISK DRIVE AND RECORDING MEDIUM EMPLOYING THE METHOD - A method of protecting information written to a recording medium includes magnetizing the recording medium to form a first magnetic pattern corresponding to information to be stored, and magnetizing the recording medium to form a protective magnetic pattern having a phase difference of 180° from the first magnetic pattern at a position adjacent to where the first magnetic pattern is formed, with adjacent bits of the first magnetic pattern opposite and the protective magnetic pattern opposite to each other. | 10-13-2011 |
20110292534 | DISK DRIVE EMPLOYING A PREAMP COMPRISING READ/WRITE PASS THROUGHS FOR CASCADING INTEGRATED CIRCUITS - A disk drive is disclosed comprising a plurality of disk surfaces and a plurality of corresponding heads. The disk drive further comprises a preamp including a first integrated circuit coupled to a first plurality of the heads. The first integrated circuit comprises a first read-output for outputting a preamplified read signal, a first write-input for receiving a first write signal, a write-output-passthrough for outputting a passthrough write signal in response to the first write signal, and a read-input-passthrough for receiving a passthrough read signal. The preamp further comprises a second integrated circuit coupled to a second plurality of the heads, wherein the second integrated circuit comprises a second read-output for outputting the passthrough read signal, and a second write-input for receiving the passthrough write signal. | 12-01-2011 |
20120008227 | HEAT TRANSFER FOR A HARD-DRIVE PRE-AMP - A substrate for mounting a preamp chip thereupon, fabricated using a stiffener layer made of a conductive material; an insulating layer provided over the circuitry area of the substrate; a circuitry made of a conductive material provided over the insulating layer; and a flap which is an extension of the stiffener layer having no insulating layer provided thereupon. The flap is fabricated to fold over the preamp chip to remove heat therefrom. | 01-12-2012 |
20120019947 | TECHNIQUE FOR PROGRAMMABLE RISE TIME IN HARD DISK DRIVE WRITER - A write channel for a hard disk drive has a write current with a programmably adjustable rise time, and includes first and second analog write data signal paths having respective resistive nodes. First and second programmable capacitors are connected to the resistive nodes, whereby changes in capacitance of the first and second capacitors changes the rise time of the write current. A programmer selectively programs the first and second programmable capacitors. The rise time programmed is selected to provide a decreased bit error rate of an on-track write process and reduced adjacent-track interference. | 01-26-2012 |
20120182640 | DUAL CHANNEL HDD SYSTEMS AND METHODS - A hard disk drive system includes a first channel module and a second channel module. The first channel module is configured to receive a first data from or transfer the first data to a first amplifier module of a hard disk assembly when reading from or writing to a first surface of a disk of the hard disk assembly. The second channel module is configured to receive a second data from or transfer the second data to a second amplifier module of the hard disk assembly when reading or writing to a second surface of the disk while the first channel module receives the first data from or transfers the first data to the first amplifier module. | 07-19-2012 |
20120212851 | Systems and Methods for Medium Contact Detection - Various embodiments of the present invention provide systems and methods for detecting contact. For example, a method for detecting head contact is disclosed that includes: receiving an interface signal operable to indicate a physical contact between a sensing device and a storage medium; band pass filtering a data set derived from the interface signal to yield a band pass filtered output; comparing the band pass filtered output to a level threshold to yield a comparator output; summing the comparator output with at least one prior instance of the comparator output to yield an aggregated value; and comparing the aggregated value to an aggregate threshold to yield a contact output. | 08-23-2012 |
20120281306 | PRINTED CIRCUIT CABLE ASSEMBLY FOR A HARD DISK DRIVE - A printed circuit cable assembly (PCCA) for a hard disk drive (HDD) is disclosed. The PCCA includes a stiffener portion having an elongated shape that includes an integrated circuit (IC) chip. The PCCA also includes a flexible portion extending from the elongated stiffener portion, wherein the PCCA is configured to be mountable on a headstack of the HDD such that an entire footprint of the IC chip overlays a metallic portion of the headstack of the HDD. | 11-08-2012 |
20120287527 | HYBRID TAPE HEAD ASSEMBLY AND DRIVE FOR ACCEPTING THE SAME - A head assembly according to one embodiment includes at least one module having magnetic transducers for reading and/or writing to a magnetic tape; electronics electrically coupled to the transducers, the electronics comprising at least one of amplifiers; bias circuitry; write drivers; write resistors; a memory device; and a chip with at least one of identification information about the head assembly, customization data, and firmware; and a connector for detachably interfacing to a drive having a head region for receiving the head assembly. A magnetic tape drive according to one embodiment includes a head region for removably receiving a head assembly; a mechanical interface to facilitate alignment of the head assembly when inserted in the head region; and a connector for detachably interfacing with the head assembly. Additional systems and methods are also presented. | 11-15-2012 |
20130083419 | DISK-BASED STORAGE DEVICE HAVING WRITE SIGNAL COMPENSATION FOR MAGNETIZATION POLARITY OF ADJACENT BITS - A hard disk drive or other disk-based storage device comprises a storage disk, a read/write head configured to read data from and write data to the storage disk, and control circuitry coupled to the read/write head and configured to process data received from and supplied to the read/write head and to control positioning of the read/write head relative to the storage disk. The control circuitry is further configured to adjust at least one parameter of a write signal for a target bit to be written to the storage disk based on respective magnetization polarities of one or more adjacent bits previously written to the storage disk. | 04-04-2013 |
20130135765 | PERPENDICULAR MAGNETIC RECORDING WRITE HEAD WITH LADDER NETWORK COMPENSATION CIRCUITRY ON SLIDER BODY FOR WRITE CURRENT OVERSHOOT AT WRITE CURRENT SWITCHING - Write enhancement circuitry on the head carrier of a magnetic recording disk drive provides additional write current overshoot beyond that provided by the write driver circuitry. The write enhancement circuitry is formed on the head carrier as ladder network blocks. A first ladder network block is a first capacitor C | 05-30-2013 |
20130155538 | DISK DRIVE WITH MULTIPLEXED READ SIGNAL AND FLY-HEIGHT SIGNAL FOR FLY-HEIGHT MONITORING DURING WRITING - A magnetic recording disk drive has a fly-height sensor on the slider that supports the read/write head. The head-disk spacing signal from the fly-height sensor utilizes the existing read path between the arm electronics (AE) module and the channel electronics module. A variable gain amplifier (VGA) on the AE module receives as one input the head-disk spacing signal and as the other input an emulated read signal. The output of the VGA is thus an oscillatory signal that emulates the read signal but whose amplitude varies as the head-disk spacing varies. A multiplexer (MUX) on the AE module multiplexes the amplified read signal from the read amplifier with the VGA oscillatory output signal on the read path back to the channel electronics module. | 06-20-2013 |
20130176640 | Systems and Methods for Adaptive Gain Control - Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing system is discussed that includes: an analog to digital converter circuit, a data detector circuit, a filter circuit, an error generation circuit, and a target parameter adaptation circuit. The analog to digital converter circuit converts an analog input into corresponding digital samples. The data detector circuit applies a data detection algorithm to a data set derived from the digital samples to yield a detected output. The filter circuit convolves the detected output with a target parameter to yield a target output. The error generation circuit calculates an error value based on the digital samples and the target output. The target parameter adaptation circuit updates the target parameter based at least in part on the error value. | 07-11-2013 |
20130222937 | Collection of Readback Signal Modulation Data - A data storage system having a read channel configured to function in a normal operation mode and a test mode. In the normal operation mode, the read channel is configured to decode a readback signal to obtain data bits. In the test mode, the read channel is configured to extract gain control loop data and/or timing control loop data from the readback signal. | 08-29-2013 |
20130250446 | Spacing Fluctuation Compensation - A method to compensate for spacing variations between a dynamic fly height (DFH) controlled read/write head and a rotating disk surface. Using a HDI sensor or equivalent indicator of touchdowns, a power profile is calculated for an arbitrary track on a disk. The profile tracks disk topography by recording touchdown power at each of a series of sectors into which the track is subdivided. The resulting power profile, smoothed and expressed as a function of sector position, substitutes for the usual constant TD power setting that provides only an uncompensated range of spacing variations. A fixed back-off spacing power is added to the power profile enabling the head to fly over the track at a constant spacing. The power profile can be calculated to account for various temperature and pressure conditions. | 09-26-2013 |
20130258514 | MICROWAVE-ASSISTED MAGNETIC RECORDING DEVICE AND METHOD USING NON-CONSTANT MICROWAVE - A magnetic recording device includes a magnetic disk and a magnetic head that performs magnetic recording to the magnetic disk. The magnetic head includes a main magnetic pole layer and a microwave generating element. The magnetic recording device further includes a microwave generating element driving current control circuit. The microwave generating element driving current control circuit, during the magnetic recording, applies a microwave generating element driving current at a first current level to the microwave generating element for a period that is from at the latest a polarity reversal of the recording current before a subsequent polarity reversal of the recording voltage, and thereafter applies another microwave generating element driving current at a second current level, which is smaller than the first current level, to the microwave generating element, or stops the application of the another microwave generating element driving current until the polarity reversal of the recording voltage. | 10-03-2013 |
20130286499 | VOLTAGE-MODE DRIVER - A method is provided. A first CMOS switch is deactivated while activating a second CMOS switch to cause the portion of the write signal to transition from a first direct current (DC) voltage to a first peak voltage. After a first interval, the second CMOS switch is deactivated while activating a third CMOS switch to cause the portion of the write signal to transition from the first peak voltage to a second DC voltage. After a second interval, the third CMOS switch is deactivated while activating a fourth CMOS switch to cause the portion of the write signal to transition from the second DC voltage to a second peak voltage After a third interval, the fourth CMOS switch is deactivated while activating the first CMOS switch to cause the portion of the write signal to transition from the second peak voltage to the first DC voltage. | 10-31-2013 |
20130301156 | ADJUSTING A PREAMP WRITE CURRENT TO APPLY AN ASYMMETRIC SIGNAL AT A WRITE HEAD - A first parameter associated with a writer preamp is defined. A write current of the writer preamp is adjusted in accordance with the first parameter so that an asymmetric signal is applied at a write head. The asymmetric signal results in symmetric writing of bits to a medium. | 11-14-2013 |
20130335847 | MICROWAVE ASSISTED MAGNETIC RECORDING AND MAGNETIC STORAGE DEVICE - Disclosed is a technique of providing a large-capacity magnetic storage device at high device manufacturing yield while keeping the reliability, the magnetic storage device enabling recording on a perpendicular magnetic recording medium having distribution of characteristics in the circumferential direction as well at high track density of 500 kTPI or more that would be expected from the average characteristics of the medium. A recording condition from is selected for each sector from a parameter table that stores a set of at least two types of recording conditions by a microwave assisted magnetic recording head including a magnetic recording pole and a high-frequency magnetic field oscillator in the magnetic storage device, and information is recorded for each sector based on the condition. | 12-19-2013 |
20140016221 | PIN-EFFICIENT READER BIAS ENABLE CONTROL - Systems and methods are included for determining a presence of an upcoming reading field during a write mode of a storage device, and initiating a read-while write (RWW) mode of the storage device in response to the sensed reading field. Initiating the RWW mode comprises warming up the reader circuitry, generating a signal in response to an end to the write operation, and activating reader bias current in response to the generated signal. | 01-16-2014 |
20140016222 | GAIN CONTROL FOR LATENCY TESTING - Approaches for determining the timing latency of a communication path are described. Some embodiments involve a method for testing timing latency. A signal is driven on a first data path and is returned through a second data path through a loop back element. The timing latency of at least a portion of the communication path that includes the first data path and the second data path is tested using the signal returned on the second data path. The gain of the second data path is adjusted to a test value during the testing of the timing latency. | 01-16-2014 |
20140029127 | Over-the-Rail Write Driver for Magnetic Storage Systems - A write driver circuit for generating a write current pulse for use by a magnetic write head includes an output stage adapted for connection with the magnetic write head and a charge storage circuit connected with the output stage. The charge storage circuit is operative in a first mode to store a prescribed charge and is operative in a second mode to transfer at least a portion of the charge stored therein to the output stage to thereby enable an output voltage level of the output stage to extend beyond a voltage supply rail of the write driver circuit. A control circuit in the write driver circuit is operative to generate at least one control signal for selectively controlling a mode of operation of the charge storage circuit. | 01-30-2014 |
20140029128 | Saturation-Based Loop Control Assistance - The present inventions are related to systems and methods for data processing, and more particularly to data processing using distortion-correction loops with saturation-based assistance. | 01-30-2014 |
20140043709 | Method and Apparatus for Reading a Non-Volatile Memory Using a Spin Torque Oscillator - A method and apparatus for reading electronic memory comprising a current source, a spin transfer oscillator, an external field source, coupled to the current source, for generating an RF signal, the spin torque oscillator positioned proximate a magnetic media comprising a plurality of bit regions of varying magnetic permeability, wherein a frequency of the RF signal varies in response to the permeability of a bit region in the plurality of bit regions being proximate the spin torque oscillator. | 02-13-2014 |
20140104716 | PREAMPLIFIER-TO-CHANNEL COMMUNICATION IN A STORAGE DEVICE - An apparatus comprising a preamplifier, a channel, and a controller. The preamplifier may be configured to read/write data to a drive with a read/write head, in response to (i) a plurality of digital control signals multiplexed to be sent/received over a first bus and (ii) one or more analog data signals sent/received over a second bus. The channel may be configured to (i) connect to the first and second bus, and (ii) send/receive the plurality of digital control signals through (a) a plurality of interconnects and (b) the first bus. The controller may be configured to send/receive the digital control signals over the interconnects. The apparatus may be configured to (i) read/write the analog data signals to the drive and (ii) generate the digital control signals, in response to one or more input/output requests received from a drive interface. | 04-17-2014 |
20140104717 | ZERO GAIN START AND GAIN ACQUISITION BASED ON ADAPTIVE ANALOG-TO-DIGITAL CONVERTER TARGET - Aspects of the disclosure pertain to a system and method for providing zero gain start (ZGS) and gain acquisition based on an adaptive analog-to-digital converter (ADC) target. The adaptive ADC target is used to collect channel characteristics and based on the adaptive ADC target, an adjusted 2T amplitude target value is generated. | 04-17-2014 |
20140126077 | PROGRAMMABLE ANALOG FEED-FORWARD TIMER FOR DYNAMIC WAVE SHAPING - A Dynamic Wave-Shaping (DWS) write driver for use in a preamp in a disk drive is described. The DWS write driver includes a Dynamic Current Booster (DCB) that adds a current component (WDCB) to the standard write driver signal (including overshoot) that is a function of the bit spacing in the write data input waveform supplied to the write driver. The invention allows dynamic control of the bit-pattern dependent overshoot amplitude without requiring significant preamp overhead. Embodiments of the Dynamic Current Booster include a programmable analog feed-forward timer at the preamp level. The boost current amplitude is a function of the time between the transitions that represent bits. In embodiments, the polarity of the boost current WDCB can be programmed to be positive or negative. | 05-08-2014 |
20140139941 | PREAMPLIFIER OUTPUT CURRENT CONTROL - One embodiment includes a preamplifier system. The system includes a reference stage configured to set a magnitude of a clamping voltage for a reference node based on a reference current generated in an adjustable reference current path. The system also includes an output stage comprising an adjustable slew current source that is configured to provide an activation current to the reference node in response to at least one activation signal, the output stage to generate an output current at an output of the output stage with a magnitude that is based on the clamping voltage. | 05-22-2014 |
20140146412 | METHODS AND SYSTEMS FOR MAGNETIC MEDIA SERVO WRITING - A method comprises generating first and second magnetic field components in a magnetic medium, the second magnetic field component substantially opposite the first. A pattern is written onto the magnetic medium, and a signal is generated by reading the pattern. The magnitude of the second magnetic field component is controlled based on an asymmetry of the signal. | 05-29-2014 |
20140168809 | TAG MULTIPLICATION VIA A PREAMPLIFIER INTERFACE - An apparatus having a controller and a preamplifier is disclosed. The controller may be configured to generate information on a serial bus coupled to a preamplifier interface. The preamplifier may be configured to (i) generate a count value in response to a clock signal synchronized to a recording medium and (ii) generate a plurality of tag signals based on the information and the count value. The tag signals may gate a read operation and a write operation of the preamplifier. | 06-19-2014 |
20140177083 | INDEPENDENTLY DRIVEN WRITE COILS - A writer assembly having two separately driven write coils allows a combined write field generated by the writer assembly to be fine turned and optimized for a particular application. Two preamplifiers may be incorporated into a printed circuit board in order to separately drive the write coils. In other implementations, there may be more than two write coils and corresponding preamplifiers. | 06-26-2014 |
20140300984 | CIRCUITS AND METHODS FOR CANCELLING A REFLECTED WAVE - Method and circuits for cancelling reflected waves from a load are disclosed. An embodiment of the method includes transmitting a signal to the bad from a current source, wherein a transistor is connected in parallel with the current source at a node. The transistor is biased so that a reflected wave at the node will cause the drain to source voltage of the transistor to increase. The drain current of the first transistor increases by way of channel length modulation when the drain to source voltage increases, the increased drain current cancels the reflected wave. | 10-09-2014 |
20140320994 | ELECTRIC FIELD WRITING MAGNETIC STORAGE DEVICE - An electric field writing magnetic storage device including: a rotatable disk including a substrate and a magnetic recording film provided on a surface of the substrate, the magnetic recording film including at least one ferromagnetic and ferroelectric layer; a writing device writing information into the magnetic recording film by means of an electric field, the writing device including a writing electrode generating a dielectric flux between the writing electrode and the substrate by having electric potential to the substrate; and a writing circuit choosing one electric potential among plurality of electric potential level and applying the chosen one electric potential to the writing electrode in every operation of writing information, wherein the dielectric flux generated according to the electric potential applied to the writing electrode by the writing circuit magnetizes the ferromagnetic and ferroelectric layer in a specific direction. | 10-30-2014 |
20140368943 | SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE, MAGNETIC DISK STORAGE DEVICE, AND ELECTRONIC APPARATUS - A semiconductor integrated circuit device has a p-type substrate to which a ground voltage is applied and a floating-type NMOSFET which is integrated on the p-type substrate and to which a negative voltage lower than the ground voltage is applied. The floating-type NMOSFET includes an n-type buried layer buried in the p-type substrate, a high voltage n-type well formed on the n-type buried layer and floats electrically, a p-type drift region formed in the n-type well, an n-type drain region and an-type source region formed in the p-type drift region, and a gate electrode formed on a channel region interposed between the n-type drain region and the n-type source region. The high voltage n-type well includes an n-type tunnel region, with a higher impurity concentration than that of the high voltage n-type well, inside a peripheral region formed so as to surround the p-type drift region. | 12-18-2014 |
20140368944 | ANALOG FRONT END FOR PROXIMITY SENSING OF TUNNELING CURRENT - A circuit includes an input that receives a current that increases as a tunneling current sensor moves closer to a media. A high gain path is operatively coupled to the input to amplify the received current as a first amplified output. The first amplified output increases until a saturation threshold is attained for the high gain path. Further increases in the received current beyond the saturation threshold are diverted from the input as an overflow current. A low gain path is operatively coupled to the input to amplify the overflow current as a second amplified output. The second amplified output increases with the overflow current as the tunneling current sensor continues to move closer to the media. | 12-18-2014 |
20150062735 | DUAL READER STRUCTURE - Implementations described and claimed herein provide a stacked dual reader with a bottom sensor stack and a top sensor stack wherein the bottom sensor stack and the top sensor stack are mirrored along a down-track direction. | 03-05-2015 |
20150098146 | PSEUDO-DIFFERENTIAL MAGNETIC RECORDING SYSTEM AND METHOD INCORPORATING A DUMMY READ ELEMENT AND A DUMMY TRANSMISSION LINE - A system including a first transmission line, a second transmission line, a first element, a second element and a differential amplifier. The first element is configured to read a storage media to generate a read signal, where the first element is connected to the first transmission line. The second element is configured to detect interference and generate an interference signal, where the second element is connected to the second transmission line. The differential amplifier includes a first input and a second input, where the first input of the differential amplifier is connected to a the first transmission line and receives the read signal, and where the second input of the differential amplifier is connected to the second transmission line and receives the interference signal. | 04-09-2015 |
20150098147 | TWO-DIMENSIONAL MAGNETIC RECORDING SYSTEMS AND METHODS FOR MINIMIZING AND ACCOUNTING FOR INTER-MODULATION OF SIGNALS INDUCED IN ADJACENT READ ELEMENTS - A system including transmission lines, read elements, and differential amplifiers. The read elements are connected in series. Each of the read elements is connected to a respective pair of the transmission lines. The differential amplifiers are connected respectively to the read elements via the transmission lines. The differential amplifiers are configured to amplify differential signals received from the respective pairs of the transmission lines. | 04-09-2015 |
20150138663 | MAGNETIC RECORDING DISK DRIVE WITH WRITE DRIVER TO WRITE HEAD TRANSMISSION LINE WITH MULTIPLE SEGMENTS HAVING DIFFERENT NUMBERS OF CONDUCTIVE TRACES - A multiple-segment transmission line in a hard disk drive enables a wider optimization range of the slope, duration and amplitude of the transmission line overshoot (TLO) wave shape. There is a first segment with two traces for connection to the write driver circuitry, an end segment with two traces for connection to the write head and at least two intermediate segments. The number of traces in a segment is different from the number of traces in the segments to which the segment is immediately connected. There is an even number of traces in each segment and the traces in each segment are interleaved. The number of segments and the number of traces in each segment can be selected to achieve the desired impedance levels for the different segments to achieve the desired wave shape for the TLO. All of the traces on the transmission line are preferably coplanar. | 05-21-2015 |
20150138664 | FPC ASSEMBLY AND DISK DRIVE - According to one embodiment, there is provided an FPC (Flexible Printed Circuits) assembly including an FPC and a reinforcing plate The reinforcing plate reinforces a part of the FPC. The reinforcing plate has a first part and a second part. The first part is disposed in a part of the reinforcing plate and formed of a material whose main component is resin. The second part is disposed in a part other than the part of the reinforcing plate and formed of a material whose main component is metal. | 05-21-2015 |
20150146319 | DISK DRIVE SLIDER WITH SENSE AMPLIFIER FOR COUPLING TO A PREAMP THROUGH A SUPPLY/BIAS LINE AND A READ SIGNAL LINE - A disk drive slider is disclosed comprising a first read element for generating a first read signal, and a first sense amplifier comprising a first input terminal coupled to the first read element, a first output terminal coupled to a first output line, and a first supply terminal coupled to a supply line. The first sense amplifier is for amplifying the first read signal to generate a first amplified read signal, the first output line is for transmitting the first amplified read signal to a preamp, and the supply line is for coupling to the preamp in order to supply power to the first sense amplifier and supply a first bias to the first read element. | 05-28-2015 |
20150302887 | Cross-Talk Measurement In Array Reader Magnetic Recording System - An apparatus for measuring cross-talk in an array reader magnetic storage system includes an array reader with multiple read heads operable to read data from a magnetic storage medium, a first preamplifier connected to a first read head, a second preamplifier connected to a second read head, and a cross-talk measurement circuit connected to the first preamplifier and to the second preamplifier, operable to measure cross-talk between a first signal from the first read head and a second signal from the second read head. | 10-22-2015 |
20150318014 | MULTIPLEXED COMMUNICATION IN A STORAGE DEVICE - A method is provided, for example, to implement multiplexed communication on an analog bus between a recording channel and a preamplifier in a storage device. A first input of read data circuitry within the recording channel is switchably connected to a first analog line of the analog bus to receive read data transmitted from the preamplifier to the recording channel over the first analog line during a read operation. In addition, a write data output of write data circuitry within the recording channel is switchably connected to the first analog line of the analog bus to transmit write data from the recording channel to the preamplifier over the first analog line during a write operation. | 11-05-2015 |
20150340062 | DIFFERENTIAL CLASS AB OUTPUT STAGE WITH DIFFERENTIAL MODE ON CHIP SUPPLY FILTER - A disk drive preamplifier integrated circuit. The integrated circuit comprises a differential output driver configured to drive readback data to an output load, wherein the output driver comprises a differential mode filter configured to filter alternating current of an on-chip power supply. | 11-26-2015 |
20160012846 | SERIAL PORT COMMUNICATION FOR STORAGE DEVICE USING SINGLE BIDIRECTIONAL SERIAL DATA LINE | 01-14-2016 |
20160027455 | MAGNETIC RECORDING HEAD AND MAGNETIC RECORDING APPARATUS - According to an embodiment, a magnetic recording head includes a main magnetic pole and a spin torque oscillator. The spin torque oscillator includes a first perpendicular free layer, a second perpendicular free layer, and a first spacer layer, each of the first perpendicular free layer and the second perpendicular free layer including a magnetic anisotropy axis in a direction perpendicular to a film plane of the spin torque oscillator. An effective perpendicular magnetic anisotropy magnetic field of the first perpendicular free layer is smaller than an effective perpendicular magnetic anisotropy magnetic field of the second perpendicular free layer, and a current is applied from the first perpendicular free layer side to the second perpendicular free layer side. | 01-28-2016 |
20160064015 | High Frequency Data Writer Field Generator Device - A data writing device may be constructed and operated with at least a data writer that has at least a write pole and a magnetic feature. A controller may selectively activate the magnetic feature to magnetically oscillate and produce a radio frequency signal proximal the write pole on an air bearing surface (ABS). | 03-03-2016 |
20160093318 | MAGNETIC HEAD, HEAD GIMBAL ASSEMBLY, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS - A magnetic head has a magnetic head slider that includes a recording element that generates a recording signal magnetic field, a microwave magnetic field generating element that generates a microwave magnetic field, a terminal electrode, and a first transmission line that interconnects the terminal electrode and the microwave magnetic field generating element. A second transmission line is connected to the terminal electrode, the second transmission line being used to transmit a microwave signal from the outside of the magnetic head slider to the magnetic head slider. A capacitor connected to the first transmission line is provided between the terminal electrode and the microwave magnetic field generating element. Accordingly, in the magnetic head, a microwave signal is efficiently propagated. | 03-31-2016 |
20160155464 | Systems and Methods for Multi-Path Preamplifier Fault Processing | 06-02-2016 |