CD/DVD DRIVE

What is a CD/DVD-ROM?

A compact disc [sometimes spelled disk] (CD) is a small, portable, round medium made of molded polymer (close in size to the floppy disk) for electronically recording, storing, and playing back audio, video, text, and other information in digital form. Tape cartridges and CDs generally replaced the phonograph record for playing back music. At home, CDs have tended to replace the tape cartridge although the latter is still widely used in cars and portable playback devices.

Initially, CDs were read-only, but newer technology allows users to record as well. CDs will probably continue to be popular for music recording and playback. A newer technology, the digital versatile disc (DVD), stores much more in the same space and is used for playing back movies.

What is a CD/DVD drive?

CD drives for computers became popular as computer application programs grew larger and it became more convenient to use a compact disk to install than a series of floppy disks. Early CD-Rom drives were slow, running at 1X or 150 kilobytes per second, but the technology quickly grew to where drives run at 52X speeds, making large application files quick and efficient to install.

A CD drive can perform a variety of tasks. With the advent of writeable and rewriteable compact disk technology, users could use the drive to back up important data or entire hard drives. The drive also can be used for listening to or copying music files including MP3s.

CD-Rom drives on the market include those that are capable of simply reading compact disks to those that can burn CDs. Speeds can vary, with most having a listing of both reading speed and recording speed. For Rewriteable CDs, there can be a third speed listed.

Components of a CD/DVD drive:

1)      Face plate

2)      Rejected motor

3)      tray

4)      Spindle motor

5)      lens

6)      lens actuator motor

7)      Logic board

8)      Connectors

Face plate: 

he front of the CD/DVD drive has a small button to eject or close the tray. This part of a CD/DVD drive is called the face plate and this is the only part that is exposed out of the cabinet.

Rejected motor:

This is the motor that helps the CD/DVD drive to move the tray in and out. This motor is present exactly behind the faceplate below the tray.

Tray:

This is a simple rectangular plastic plate with a gap in between it. This is the place where a CD/DVD is place to work on it.

Spindle motor:

This motor is place under the CD/DVD disk. Its purpose is to rotate the CD/DVD. A spindle motor generally has rpm of 3500/4500/5400/7200/10000/12000/15000.

Lens:

As the CD/DVD is an optical storage devices we use lens to read and write data on these disks. Depending upon the power of the lens the working power of the drive changes.

Lens actuator motor:

It is connected to the lens with an arm. The function of the lens actuator motor is to move the lens from inner edge to outer edge of CD/DVD disk in a CD/DVD drive.

Connectors:

As I have told u before these connectors are of two types:

1)      IDE(integrated drive electronic)

2)      SATA(serial advanced technology attachment) 

                                              IDE Connectors

These types of connectors have 3 compartments in the hard disk and they are:

1)      Data transfer

2)      Jumper section

3)      Power port

Power port:-

The hard disk requires some electrical power to run the platter, spindle motor and the head actuator motor. This power is supplied to the hard disk by the SMPS after filtering the given supply of 230volts to the required amount of power. This port consists of 4 bold pins.

Data transfer:-

The data in the hard disk is accessed by the CPU through the data transfer port given to the hard disk drive. This port is connected to the mother board directly by an IDE data cable. This port consists of 39-40 delicate pins in two rows.

Jumper section:-

This section of port in a hard disk is used when we use a single IDE cable to connect two hard disks to a motherboard.  This port consists of 6 or 8 delicate pins in it in 3 rows and 3 or 4 columns. Jumper is a small clip type thing that is used to join any two ports in same column but we should not join the pins in the same row. When we add two hard disk drives to a single IDE slot in mother board we connect two hard disks to the connector above the pins which have short length between them are connected to hard disk drives and the third one is connected to the motherboard. The hard disk connected to the top port is called master and the second one is called the slave. These master and slave are mentioned to the computer using the jumper. The position of jumper to mention master and slave are given in the images below.

                                                                     SATA connectors

These types of connectors have 2 compartments in the hard disk and they are:

1)      Data transfer

2)      Power port

Data transfer:-

The data in the hard disk is accessed by the CPU through the data transfer port given to the hard disk drive. This port is connected to the mother board directly by an SATA data cable. This port consists of 7 golden strips in a single row like the strips in an USB port.

 Power port:-

The hard disk requires some electrical power to run the platter, spindle motor and the head actuator motor. This power is supplied to the hard disk by the SMPS after filtering the given supply of 230volts to the required amount of power. This port consists of 15 golden strips like the strips in data transfer port. If the SMPS used has an IDE power cable we can use an IDE to SATA converter power cable

Note: - there is no jumper section in the SATA hard disks because we can connect only one hard disk in

             SATA cable.