TEAR DOWN PROCESS OF

SEAGATE U6 MODEL T340810A

HARD-DRIVE

Submitted to

Prof. Pradeep Dixit

By

Udit Kumar (163110065) & Abhishek Sharma (120100061)

Tear Down Process of Seagate U6 Model ST340810A Hard-Drive

Hard-Drive: Introduction about components The hard drive, which typically provides storage for data and applications within a computer, has four key

components inside its casing -- the platter (for storing data), the spindle (for spinning the platters), the

read/write arm (for reading and writing data) and the actuator (for controlling the actions of the read/write

arm). Only the most technically proficient IT professionals should attempt to work on the components inside

a hard drive.

Major Components

1. Platters: The platters are the circular discs inside the hard drive where the 1s and 0s that

make up your files are stored. Platters are made out of aluminum, glass or ceramic and

have a magnetic surface in order to permanently store data. On larger hard drives, several

platters are used to increase the overall capacity of the drive. Data is stored on the

platters in tracks, sectors and cylinders to keep it organized and easier to find.

2. The Spindle: The spindle keeps the platters in position and rotates them as required. The

revolutions-per-minute rating determines how fast data can be written to and read from the

hard drive. A typical internal desktop drive runs at 7,200 RPM, though faster and slower

speeds are available. The spindle keeps the platters at a fixed distance apart from each

other to enable the read/write arm to gain access. 3. The Read/Write Arm: The read/write arm controls the movement of the read/write heads,

which do the actual reading and writing on the disk platters by converting the magnetic

surface into an electric current. The arm makes sure the heads are in the right position

based on the data that needs to be accessed or written; it's also known as the head arm

or actuator arm. There is typically one read/write head for every platter side, which floats 3

to 20 millionths of an inch above the platter surface. 4. Actuator: The actuator or head actuator is a small motor that takes instructions from the

drive's circuit board to control the movement of the read/write arm and supervise the

transfer of data to and from the platters. It's responsible for ensuring the read/write heads

are in exactly the right place at all times

Fig: 1 A typical image of Hard-Drive

Step 1 Bottom view of hard-drive (as received), Screwed were taken out

Fig: 2 Hard-Drive as received

Step 2 Top and bottom view of drive after removal of cover

Fig: 3 Top and bottom view after removal of cover

Step 3 PCB board was taken out.

Fig: 4 components of top part

Step 4 Tear down of hard-drive main

Fig: 5 Platter, spindle, actuator & read write arm assembly

Fig: 6 all parts dissembled

Step 5

Fig: 7 Removal of IC bonded by BGA (ball grid array)

Step 6 Removal of encapsulation from IC (bonded by BGA)

Fig: 8 (a) & (b) Removal of upper encapsulation by grinding & polishing

Fig: 9 cross-section image of fig: 8(a)

Fig: 10 Top view of fig: 8 at high magnification

Fig: 11 Cross- section view of fig: 8(b)

In fig: 11 you can see the basic wirebonding from die connecting it to copper pad, solder balls are also

shown in in image 9.

Actuator

Fig: 12 Actuator and reading writing arm

Spindle

Fig: 13 Spindle

The spindle keeps the platters in position and rotates them as required

Working of Hard-Drive Platter, divided into billions of tiny areas. Each one of those areas can be independently magnetized (to

store a 1) or demagnetized (to store a 0). Magnetism is used in computer storage because it goes on

storing information even when the power is switched off. If you magnetize a nail, it stays magnetized

until you demagnetize it. In much the same way, the computerized information (or data) stored in your

PC hard drive or iPod stays there even when you switch the power off.

Fig: 14 Working of Hard-Drive (Schematic)

1) Actuator that moves the read-write arm. In older hard drives, the actuators were stepper

motors. In most modern hard drives, voice coils are used instead. As their name suggests, these

are simple electromagnets, working rather like the moving coils that make sounds

in loudspeakers. They position the read-write arm more quickly, precisely, and reliably than

stepper motors and are less sensitive to problems such as temperature variations.

2) Read-write arm swings read-write head back and forth across platter.

3) Central spindle allows platter to rotate at high speed.

4) Magnetic platter stores information in binary form.

5) Plug connections link hard drive to circuit board in personal computer.

6) Read-write head is a tiny magnet on the end of the read-write arm.

7) Circuit board on underside controls the flow of data to and from the platter.

A typical magnetic region on a hard-disk platter (as of 2006) is about 200–250 nanometers wide (in the

radial direction of the platter) and extends about 25–30 nanometers in the down-track direction (the

circumferential direction on the platter), corresponding to about 100 billion bits per square inch of disk

area (15.5 Gbit/cm2). The material of the main magnetic medium layer is usually a cobalt-based alloy,

which can be magnetized or demagnetized by the help of a rotating head.

References

[1] David Nield, The Four Major Components of a Hard Drive, http://smallbusiness.chron.com

[2] Chris Woodford., Hard drives, http://www.explainthatstuff.com

Fig: 15 IBM Magnetic Storage device with single read write arm