Hdd voice coil driver

Realization of an adaptive voltage driver for voice coil motor. Yes, i do think that there is a driver in the pcb of the hdd, but i am not using it. A simple 2 transistor output driver will provide the current that your inductor needs. If you tear the driver cone or membrane in the case of orthos or, as is i believe the case with mine since i see no physical damage or distortion to the cone, if the voice coil slightly separates from the cone, the headphones may sound wrong somehow. Choose prv audios phenolic d4260ph 2 exit horn driver for extreme high output applications where clean, controlled midrange and vocal content is required.

Our voice coil actuators are available in both standard as well as custom sizes. We have developed a highspeed laser shutter based on voicecoil actuators found in generic hard disk drives. The performance obtained, when it is fully tuned, is the same as a. Hard disk drive with voltage driven voice coil motor and model. You are on the right track but need a clearer understanding of the amplification needed and of what you will need to provide the power level. The lv8498ct is a constant current driver ic for voice coil motors that supports i 2 c control integrating a digitalanalog converter dac. Current hdd s speed is too fast to cause this ic hot and damaged. The term is also used for voice coil linear motors, such as those used to move the heads inside hard disk drives, which produce a larger force and move a longer. The hard disk drive hdd has been one of the most important storage devices since its invention. This hack uses the voice coil of a used hard drive to act as a laser shutter. Pdf halbach magnetic circuit for voice coil motor in hard disk. Hard disk drive with voltagedriven voice coil motor and modelbased control abstract.

Approaches to improving head positioning accuracy in a hard disk drive, by reducing air pressure fluctuations that would otherwise cause unwanted coil torsion in a voice coil actuator, include a voice coil actuator having a streamlined structure configured to affect the flow of air acting upon a coilsupporting arm. You might be able to make this something you can position with a given duty cycle at a much higher frequency by adding a spring. Linear voice coil motors actuators and micro voice coil. Voice coil actuator controls the movement of a coil toward or away from a permanent magnet based upon the amount of current flowing through it. Majority of the problems tend to be with the driver electronics associated with it. A stepper would be too sloppy, be too slow horrid access time, and not have enough steps, even with gearing to handle all of the cylinders tracks on a hdd platter. The adaptation of the driver compensates for the variations of vcm resistance and is performed either during seek operations and track following. A tutorial on control design of hard disk drive selfservo. Current command of the voice coil motor vcm has been preferred so far, due to. The paper presents a novel approach for driving a voice coil motor vcm in a hard disk drive hdd, based on an adaptive voltage driver. Supplied with mounting card for easy wire connection and mounting. Hard disk drive with voltagedriven voice coil motor and model. Original, voice coil motor referred to the linear actuators that drive the coils of speakers, but recently the motors for driving hard disk drive hdd heads are also. I have done videos of this in the past but never a tutorial on how it is done.

Its well within the capabilities of an arduino to drive one of these. The max14570 is a highefficiency voice coil motor vcm driver ideal for use in powersensitive autofocus camera applications. Be used to drive hdd spindle motor or voice coil motor. To get the latest driver, including windows 10 drivers, you can choose from our list of most popular hard disk controller downloads or search our driver archive for the driver that fits your specific hard disk controller model and your pcs operating system. Logic board the controller circuit board of the hdd, it communicates with the processor and controls the relevant components of the hdd drive.

Softwarewise, its a pid loop with a lookup table of raw hall effect adc readings to arm positions. The streamlined structure comprises an upper surface and a lower surface. Voltage driven hard disk drive with voice coil modelbased. The vcmc is based on a new multirate prefilter, which replicates the behavior of a current loop by using a model of the voice coil motor and its driver, including the saturation of the power stage. To meet the power handling capability required for a. By controlling the vcm current or, alternatively, acceleration by means of a vcm driver, a typical hdd servo system directs a vcm to place a slider at a requested track position. In the last log i mentioned the driver circuit for the voice coil. A hard disk drive hdd, hard disk, hard drive, or fixed disk is an electromechanical data storage device that uses magnetic storage to store and retrieve digital data using one or more rigid rapidly rotating platters coated with magnetic material. The armatures are attached to this coil and move in and out over the surface with it. That certainly couldnt be done with a normal motor and in fact, hard drive heads are moved with a voice coil actuator, much in the same way that a. Hardware is an arduino mega, a seeed motor control shield, voice coil pulled from a hard drive, laser from a cat toy, a1 hall effect sensor, magnets, hot glue, etc. Difference between flash storage and hard drive compare. Seems like there is no end to the uses of old hard drives.

Next chip is voice coil motor controller or vcm controller. Pdf rotarytype voice coil motors are widely used as actuators in hard disk. The most important part of this program is the table of values stored in the eeprom, because this pattern sets the phase relationships between the fets and consequently the voltage waveforms that the coils see. The voice coil arm position in a hdd is based on feedback of position based on data read from the rotating magnetic platter.

Without this feedback the arm is in openloop and goes from one end to the other based on the direction of the coilcurrent. Actuator, voice coil, and motor assembly control and drive the arm holding the sensors that are used to write and read the information. Arduino controlling a laser with a hard drive voice coil. I plan to use this to raise or lower a flag attached to the. Chris explores some oldschool hard drives and discusses the difference between classic stepper motor actuators vs the modern voice coil. The new l7208 hdd motor controller integrates all of the circuits needed to control and drive the hdd spindle motor and voice coil actuator including all the necessary powerfet devices and is designed to save space and to minimize the drives power consumption.

China all in 1 hdd docking station driver manufacturers wholesale 2020 high quality all in 1 hdd docking station driver products in best price from certified chinese 3 function in one wholesalers, mobile station manufacturers, suppliers and factory on. It uses an ultraminiature wlp package and includes a current detection resistor for constant current control, which makes the ic ideal for miniaturization of camera modules intended for use in cameraequipped mobile phones. A hard disk voice coil assembly, also called actuator, is a linear control device within a hard drive responsible for positioning the read write heads. Magnet application products voice coil motors electronics and. Most any hdd made since 1980 has no steppers at all. Hard disk drive with voltage driven voice coil motor and.

This is a simple program for a pic16f84 that changes the bit pattern for switching the fet coil drivers. Bios corrupt will cause the hdd cant be recognized, be recognized incorrectly, etc. Hard disk drive voicecoil laser shutter actuator hacked. Driving hard drive voice coil actuator with pwm electrical. According to the features of accessing data on disk, hdd servo systems mainly involve three kinds of control tasks 3. A voice coil consisting of a former, collar, and winding is the coil of wire attached to the apex of a loudspeaker cone. Voltage driven hard disk drive with voice coil modelbased control. The driver incorporates surface mount technology to achieve an exceptional power density. A servo system in a hard disk drive hdd controls the voice coil motor vcm, which in turn affects slider movement. I dont think you may drive the coil without any current amplifier.

Here i show you how to turn an old hard drive into a speaker. You can download the source code and and additional information of this vcm on. A hard disk drive consists of following components. We have developed a highspeed laser shutter based on voice coil actuators found in generic hard disk drives. In this paper, we describe the voice coil modelbased control vcmc, a new solution for driving the voice coil motor vcm in hard disk drives hdds, in. Precision position control of a voice coil motor using selftuning. The goal of this article is to show you how a modern hard disk drive or hdd built. Prv audio d4260ph 2 compression driver 4 voice coil. In this paper, we describe the voice coil modelbased control vcmc, a new solution for driving the voice coil motor vcm in hard disk drives hdds, in which the usual current driver for the vcm has been replaced by a voltage driver. The moving coil actuators, ncc type sometimes referred to as voice coils are typically. Optional output slewrate control and spreadspectrum oscillator reduce conducted noise and radiated.

Its also possible to use the driver chips from the original hard disk pcb to get an idea of the sort of chips used, this site has a listing of various driver chips with links to datasheets, but they are usually much more complicated since they often combine both the spindle motor driver and the voice coil driver readwrite head into one package. What are its main parts, how do they look and what are these parts names and abbreviations. In this paper we describe a head servopositioning system for hard disk drives hdds, in which the usual current command for the voice coil motor has been replaced by a simpler voltage command. The si9961a is a linear actuator voice coil motor driver suitable for use in disk drive head positioning systems. It provides the motive force to the cone by the reaction of a magnetic field to the current passing through it. Heres a little bit more info on that particular piece of our setup. Voice coils are relatively simple structures, but have the power to make your speakers and hard drives work. Applying a voltage across the terminals of the motor causes the motor to move to one direction. If you actually burnfuse the voice coil, usually it results in no sound at all. You can choose from either the moving magnet ncm type or moving coil type ncc type. We have enhanced the shutter with a new driver circuit described below and a notched flag, achieving 500ns rise time and submicrosecond pulse durations.

According to incomplete statistics, 70% hdd fault were caused by this motor combo ic damage. A hard disk voice coil assembly, also called actuator, is a linear control device. In this paper, we describe the voice coil modelbased control vcmc, a new solution for driving the voice coil motor vcm in hard disk drives hdds, in which the usual current driver for the vcm has been replaced by a. Voice coil actuators used in hard disk systems have an acceleration to current transfer function. The actuator system is composed of a voice coil motor vcm, shaft axis, arm and suspension. A massive motor and 4 diameter voice coil on a kapton former combine for watts rms power handling. Essentially this is just an adjustable constant current source, which displaces the lens within its magnetic harness. The si9961a contains all of the power and control circuitry necessary to drive the vcm that is typically found in 31 2 inch hard disk drives and optical disk drives. It consists of a copper coil wound around a former and a permanent magnet. The max14570 utilizes a switching output topology to provide high efficiency over the entire input supply voltage range.

The voice coil actuator in the disk generally has no natural position that it springs to as is the case with speaker voice coil actuators. Linear dc motors, voice coil motors vcm or voice coil actuators vca are the simplest type of electric motors. The question is how is the voice coil controlled, using a scope on an old drive you can see there is obviously ac present, so i put a circuit togther that reverses the polarity acrross the coil controlled by a pwm output from a pic, it works but the coil gets to its full movement within a small deviation from 50% symmetry, and its just as good. The so called motor turned out to be a voice coil, which is a thing that i have never dealed with before. There are a number of people offering onweb examples of hdd voice coil drivers used for other purposes. Chris explores some oldschool hard drives and discusses the difference between classic stepper motor actuators vs the modern voice coil style. You might be able to make this something you can position with a given duty cycle at. I am using a direct connection to the head there are 2 wires on the top. Hard disk controller drivers download for windows free. The linear voice coil motor vcm is a direct drive and hysteresisfree device used for providing.

As snoopen says you want a voice coil driver or actuator. Us20150009591a1 streamlined voice coil actuator for hard. Vcms voice coil motors glossary of magnet terms rare earth. The ba6832fs is a voice coil motor driver used for moving the heads of hard disc and massstorage floppy disc drives. Hard disk drive with voltagedriven voice coil motor and. Vibration suppression of a hard disk driver actuator arm. Voice coil motor driver with pwm input, 800 series the 800 series is a high performance, cost effective dc motor driver to implement intelligent motion control. China all in 1 hdd docking station driver, all in 1 hdd. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces. A high performance, dual channel, cost effective dc motor driver to implement intelligent motion control with analog inputs.