LG DRD-841B Service Manual

INTRODUCTION

GENERAL FEATURE

SPECIFICATIONS

1. SUPPORTED SYSTEM

¥ IBM Compatible Pentium 133MHz or Above (with PIO mode 4, TX chip set recommended)

2. SUPPORTED OS

3. GENERAL PERFORMANCE

¥ Data Transfer Rate ...........................................................................................Sustained Data Transfer Rate

DVD (Outer side) : Approx. 5,400 kbytes/sec DVD (Inner side) : Approx. 2,700 kbytes/sec CD (Outer side) : Approx. 4,800 kbytes/sec

CD (Inner side) : Approx. 2,100 kbytes/sec

¥ Data Buffer Capacity.......................................................................................................................512 kbytes

¥ Access Time..................................................................Random Access DVD : 130ms Typical (4X)

CD : 90ms Typical (32X)

4. POWER REQUIREMENTS

¥ Voltage ........................................................................................................................................+5V DC +5%

+12V DC +5%

¥ Ripple .....................................................................................................................................+5V : 100mVp-p

+12V : 100mVp-p

¥ Current .........................................................................................+12V : 400mA (Average), 0.9A (Maximum)

+5V : 500mA (Average), 1.2A (Maximum)

5. AUDIO PERFORMANCE

¥ Frequency Response.......................................................................................................20Hz~20KHz(+3dB)

¥ S/N Ratio (IHF-A+20kHZ LPF) ..........................................................................85 dB (Typical at 1 KHz 0dB)

80 dB (Limit at 1 KHz 0dB)

¥ T.H.D. (IHF-A+20kHZ LPF)...............................................................................0.05% (Typical at 1 KHz 0dB)

0.15% (Limit at 1 KHz 0dB)

¥ Channel Separation (IHF-A+20kHZ LPF) .................................................................................75 dB(Typical)

70 dB(Limit)

¥ Output Voltage (1kHz 0dB) 47K½ Load ..................................................................................0.8Vrms +20%

¥ Headphone Level (1kHz 0dB) 33½ Load.................................................................................0.6Vrms +20%

¥ Enhanced IDE interface ¥ Internal 5.25 inch, halfheight DVD-ROM Drive ¥ 130ms (Typical) Random Access Time (DVD) ¥ 90ms (Typical) Random Access Time (CD) ¥ Supports 4X (max) Rotational Modes in DVD Mode ¥ Supports 32X (max) Rotational Modes in CD Mode ¥ Max 5,400 kB/sec Sustained Transfer rate in DVD mode ¥ Max 4,800 kB/sec Sustained Transfer rate in CD mode ¥ Photo-CD Multisession Disc Spec compliant ¥ Multimedia MPC-3 Spec compliant ¥ Power Tray Loading/Ejection Mechanism ¥ 3-Way Eject Support (Software, Open/Close Button,

Emergency Eject)

¥ Closed Enclosure ¥ Built-in ATAPI Interface Controller ¥ Software Volume Control ¥ Easy CD-Audio Play front panel Controls ¥ Front panel Volume Control for Headphone Output ¥ Built-in MODE-1 ECC/EDC ¥ MTBF (125,000H) POH (at 10% Utilization) ¥ PIO Mode 4 & Multiword DMA Mode 2 Support ¥ Horizontal/Vertical Mounting ¥ Digital audio output connector ¥ Digital audio through ATAPI Interface ¥ Spin-down Mode for energy saving

¥ MS-DOS (Ver 3.1 or Higher) ¥ Windows 3.1/95/98 ¥ Windows NT (Ver 4.0)

¥ OS/2 Warp (Ver 3.0) ¥ Solaris (Ver 2.4 or Higher) ¥ Linux Õ96 Slacware (Ver 3.1.0)

This service manual provides a variety of service information. It contains the mechanical structure of the DVD-ROM Drive together with mechanical adjustments and the electronic circuits in schematic

form. This DVD-ROM Drive was manufactured and assembled under our strict quality control standards and meets or exceeds industry specifications and standards.

LOCATION OF CUSTOMER CONTROLS

(1) Digital Audio Ouput Connector

This is a digital audio output connector or Video CD output connector. You can connect this to the digital audio system or Video CD Board.

(2) Analog Audio Output Connector

The Audio Output Connector connects to a sound card. The supplied audio cable is a SoundBlaster®type cable. If you have a different sound card, you will need to contact the sound card manufacturer to obtain the proper cable for that card. This CABLE is necessary to play audio CD’s.

(3) Master/Slave/CSEL Jumper

These three jumpers are used to set the DVD-ROM Drive to either a Master, Slave, or CSEL drive.

(4) Interface Connector

This 40-pin connector is used to transfer and control signals between the DVD-ROM Drive and your PC. Connect the 40-pin IDE cable in your PC to this connector.

(5) Power-in Connector

Attach a power cable from the computer’s power supply to this connector.

COMPACT

DVD

BUSY

ROM

DIGITAL ANALOG

INTERFACE POWER

DR CSM

SLA

GLG39 1

+12

GND

40 2

AUDIO AUDIO

FRONT VIEW

BACK VIEW

(1) Headphone Jack

3.5mm jack for monitoring the audio signal from audio CDs.

(2) Headphone Volume Control

Adjusts the headphone sound level.

(3) Emergency Eject Hole

Insert a paper clip here to eject the drawer manually or when there is no power.

(4) DVD Indicator

The DVD Indicator lights during DVD disc data-read operations.

(5) Busy Indicator (DVD, CD)

The Busy Indicator flickers during initialization and data-read operations.

(6) Disc Drawer

Accepts a CD-ROM/DVD-ROM disc on its tray.

(7) Play/Skip Button

When an Audio CD is in the Disc Drawer, pressing this button will start playing audio CDs from the first track. If an audio CD is playing, pressing this button will skip to the next track.

(8) Open/Close/Stop Button

This button is pressed to open or close the CD tray. The button works only when the main power switch is on. If an audio CD is playing, pressing this button will stop it, and pressing it again will open the tray.

1. CABINET and CIRCUIT BOARD DISASSEMBLY

1-1. Bottom Mecha

A. Release 4 screws (A) and remove the Bottom Mecha

in the direction of arrow (1). (See Fig.1-1)

1-2. Front Bezel Assy

A. Insert and press a rod in the Emergency Eject

Hole and then the CD Tray will open in the direction of arrow (2).

B. Remove the Tray Door in the direction of arrow

(3) by pushing the stoppers forward.

C. Release 3 stoppers and remove the Front Bezel Assy.

1-3. Cabinet and Main Circuit Board

A. Remove the Cabinet in the direction of arrow (4).

(See Fig. 1-3)

B. Release 4 hooks (a) and remove the Clamp in the

direction of arrow (5). C. Remove the CD Tray drawing forward. D. Remove the Main Circuit Board in the direction of

arrow (6). E. At this time, be careful not to damage the 4

connectors, are positioned at right side, of the Main

Circuit Board.

2. DECK ASSY DISASSEMBLY

2-1. Base Assy

A. Release 2 screws (C) and 2 Stoppers (D). B. Separate the Base Assy in the direction of arrow (7). C. Release 2 screws (E) and remove the Frame Assy

Up/Dowm.

(4)

(6)

(5)

Main Circuit Board

Hooks(a)

Clamp

Cabinet

(A)

(1)

Fig. 1-1

Fig. 1-2

DISASSEMBLY

Fig. 1-3

Tray Door

Stoppers

CD Tray

Emergency Eject Hole

Front Bezel Assy

Bottom Mecha

(7)

(8)

(E)

(D)

(E)

(C)

Fig. 1-4

Base Assy

Frame Assy Up/Down

(3)

(2)

2-2. Pick-up Unit

A. Remove the skew spring. B. Remove the Pick-up Unit.

2-3. Feeding Motor Assy

A. Remove the Feeding Motor Assy by pushing the 2

hooks(b).

B. At this time, be careful the hooks of the Base Pick-up.

Fig. 1-5

Fig. 1-6

Pick-up Unit

Skew Spring

Feeding Motor Assy

Base Pick-up

Hooks(b)

INTERNAL STRUCTURE OF THE PICK-UP

1. Structure of the Pick-Up

F-COIL

T-COIL

F+

F-

T-

T+

5K VOLUME

1.5K VOLUME

0.1u

HF MODULE

LD (DVD)

LD (CD)

MONITOR PD(DVD)

MONITOR PD(CD)

PHOTO DETECTOR (DVD)

PHOTO DETECTOR (CD)

< for CD >

< for DVD >

D1 D2 D3 D4 D9

D10

D3 D4 D1 D5

7 6 5

G3 G1

I-IN

LD G2

NC2

NC1

VCC

1 2

VCC (CD)

A (CD)

B (CD)

C (CD)

E (CD) F (CD)

1/2VCC (CD)

GND (CD)

LD (CD)

MO-PD (CD)

VR (CD)

VCC (DVD)

A (DVD)

B (DVD)

E (DVD)

F (DVD)

1/2VCC (DVD)

GND(DVD)

LD(DVD)

HF (+5V)

MO-PD (DVD)

VR (DVD)

PN301-3 PN301-9

PN301-10

PN301-7

PN301-8

PN301-11 PN301-4

PN301-6 PN301-5

PN301-2 PN301-1

PN301-30

PN301-25

PN301-24

PN301-26

PN301-27

PN301-29

PN301-23

PN301-22

PN301-20

PN301-19

PN301-18

PN301-16

PN301-15

PN301-13

PN301-14

1) Focus Error Signal Ð> A - B

¥ In case of CD Disc

This signal is generated in RF AMP IC (IC301 : SSI3721) and controls the pick-upÕs up and down to focus on CD Disc.

2) Tracking Error Signal (3-Beam Method) Ð> E - F

¥ In case of CD Disc

This signal is generated in RF AMP IC (IC301 : SSI3721) and controls the pick-upÕs left and right shift to find the track on CD Disc.

3) RF Signal Ð> A+B+2C

¥ In case of CD Disc

This signal is converted to DATA signal in DSP IC (IC701 : CXD3011R-1).

2. Structure of the Photo Diode (CD)

Infrared laser

Pick-Up module

Photo Diode

Tracking

Focusing

(As seen from light

receiving side)

1) Focus Error Signal Ð> B - A

¥ In case of DVD Disc

This signal is generated in RF AMP IC (IC301 : SSI3721) and controls the pick-upÕs up and down to

focus on DVD Disc.

2) Tracking Error Signal (DPD Method) Ð> Phase (F) - Phase (E)

¥ In case of DVD Disc

This signal is generated in RF AMP IC (IC301 : SSI3721) and controls the pick-upÕs left and right shift to find the track on DVD Disc.

3) RF Signal Ð> A+B+E+F

¥ In case of DVD Disc

This signal is converted to DATA signal in DSP IC (IC701 : CXD3011R-1).

3. Structure of the Photo Diode (DVD)

(As seen from light

receiving side)

Red laser

Pick-Up module

Photo Diode

Tracking

Focusing

PN301

R301

R302

C321

R319

Q302

D303

C301

CD LD

CD PD

DVD LD

IC301 SSI3721

DVD PD

Q301

D301

R321

R303

R304

Vcc

DVD PD DVD-

DVD LD

CD PD

CD-VR

CD LD

DVD-LD(LASER DIODE)

CD-LD(LASER DIODE)

PICK-UP Unit

Monitor Diode

1-2. APC Circuit Operation

It drives the LD to the constant current and adjusts the LD input current , so that the output current is constant. IC301 (SSI3721) Pin , : PD IN, Monitor Input of Laser diode APC IC301 (SSI3721) Pin , : LD OUT, External Current Driver Control output of the LD (Laser Diode)

The detect current from the monitor diode converts to the I/V (Current/Voltage) at the external resistor. Beforehand, it adjusts a fixed level over for a standard GND. If this voltage inputs to the PD IN (IC301 Pin 21, 23), it is amplified about 36.4 times (about 31.2dB). So this voltage outputs from the LD OUT (IC301 Pin 22, 24).

The LD driving element (Q301/Q302) uses the TR more than 200hfe, and controls LD OUT (IC301 Pin 22,

24) connected to the base of Q302/Q301. The APC control for the each DVD/CD sets Register of the IC301 (SSI3721) according to Disc in the µ-COM.

DESCRIPTION OF CIRCUIT

1. APC (Automatic Power Control) Circuit

1-1. APC Circuit Constitution

24 26 27

7910

CD (A, B, C)

CD (A, B)

DVD (A,B, E, F)

SUM AMP

DVD RF

CD RF

15 16

11 12

13 14

AMP

MUX

ATT

AGC

GCA

SUM

AMP

BUFF

MUX

SIGO

To IC701 3

To IC701 143

To IC701 13

To IC202 119

GCA

Phase Detector

DVD (A, B)

DVD (E, F)

CD (E, F)

Pick-up Unit

PN301

IC301

SSI3721

2. RF Amplifier Circuit

2-1. RF AMP Constitution

FOCUS & TRACKING SERVO PROCESS

SLED(Feed) SERVO PROCESS

Pick - Up

IC301

RF AMP SSI3721

E-F

(A. B. C. E. F)

DVD (A. B. E. F)

TE/ DPD TE

SELECTOR

Generating

DPD TE

Generating

FOCUS ERROR DETECTOR

FOCUS & TRACKING

ACTUATOR

IC501

DRIVE BA5983FP

IC701

CD/DVD SERVO & DSP CXD3011R-1

F+ F-T+ T-

LEVEL SHIFT

FAO

TAO

D/A

DIGITAL

EQUALIZER

(AUTO ADJUSTMENT CIRCUIT)

SLED

Control

Signal

A/D

TE FE

SAO

SLED MOTOR

Hall Sensor

PHO - C

PHO - A

FEED. MOTOR+

FEED. MOTOR-

LEVEL SHIFT

IC501

Q501

DRIVE BA5983FP

KTD1304

IC502

OP AMP NJM3414AM

IC201

u-COM

SLGNCHG

SLED CLK

F-E

B-A

A-B

3. Focus/Tracking/Sled Servo Circuit

3-1. FOCUS, TRACKING & SLED SERVO PROCESS

3-2. Focus Servo for CD/DVD

Focus Servo for CD/DVD is based on focus error signal generated from RF AMP (SSI3721). It standardizes the laser beam (CD : A, B, DVD : A, B) radiated from the pick-up. Each other focus gain or path is made at the SSI3721 (IC301) according to the disc, Focus Error signal output from the FE terminal and input to Servo IC (IC701 CXD3011R-1). After the first amplification of this signal, the signal is converted to A/D and input to Digital Equalizer Block assigned the most important part at the Focus Servo, and generates the focus servo with coefficient value set at the µ-COM through the Digital Filter. At this Digital Equalizer, auto adjustment for Focus Balance or Focus Loop Gain occurs and the basic offset value for pick-up is accepted on the balance mode, and set the focus standard level to this value. After the signal for Focus Servo is converted to the D/A and output through FAO (IC701 CXD3011 ). This signal drives Focus Actuator through the Focus Drive IC (IC501:BA5983FP).

3-3. Tracking Servo for CD/DVD

For Tracking Servo, CD uses 3 Beam method (E-F), DVD uses DPD (Differential Phase Detect) method [Phase (F) - Phase (E)] According to the disc, Tracking Error is set at SSI3721, Gain or Path differs from each other, and the generated signal output through the TE terminal. This signal input to TE of IC701, after the first amplification, and converted to A/D. The signal converted to A/D input to the Digital Equalizer assigned the most important part at the Tracking Servo, Tracking Servo Gain is generated with Digital Filter coefficient value set according to the disc at the µ-COM.

* Tracking signal is converted to D/A through the pin TAO terminal of IC701 and input to IC501

(BA5983) tracking drive. This drive drives the tracking actuator actually.

3-4. Sled Servo (Feed Servo) for CD/DVD

Sled servo operates related with a tracking servo basically It goes with the progressive track speed according to the disc rotation speed. Sled drive voltage is generated with a accumulated capacity of tracking error signal and is applied sled movement voltage according to the track movement capacity, and this voltage outputs to the pin FAO of IC701. This value is the sled motor drove by the IC501 (Sled drive : BA5983FP). But, the shift speed for pick-up is not controlled and broke with a only sled servo, itself, in the data access mode, and the feedback is used according to the sled shift speed at this time. So, the accurated shift speed for pick-up is controlled added to the sled signal. The hall sensor is used in the feedback and SLGNCHG (6) output at the µ-COM (IC201) is used with it in the sled kick or break.

113

112

113

E A B

PICK-UP

SPINDLE MOTOR

A+B+2C

CD RF

DVD RF

A+B+E+F

IC201

IC701

PLL BLOCK

DVD RF

CD RF

Motor

Hall Sensor

HU+ HUHV+ HVHW+ HW-

Speed Monitoring

u-com

CD/DVD SERVO & DSP

CXD 3011R-1

IC301

RF AMP

SSI3721

IC202

DVD DSP

CXD 1866Q

IC503

OP AMP

NJM2100S

IC401

DRIVE BA6859A

SPINDLE SERVO PROCESS

LEVEL SHIFT

A, B, 2C

A, B, E, F

SUM AMP

IC302

AD8012

MDP CD

SPDG0 SPDG1

4. Spindle Servo Circuit

4-1. SPINDLE SERVO PROCESS

4-2. Spindle Servo for CD/DVD

DRD-841B consists of the three spindle control respectively. (1) DVD x 4 : CAV (DVD Single, Dual Layer) (2) CD x 16 (max.) : CAV (CD-DA, CD-RW, Video-CD, Host command stand-by of CD-ROM and CD-R) (3) CD x 32 (max.) : CAV (CD-R, CD-ROM play mode) In the spindle speed control mode respectively. CD x 16(Max)/CD x 32(Max) CAV drives CAV servo with PLL of RF data read and received MDP CD. (Pin 117 of IC701) DVD x 4(Max) CAV drives CAV servo with FG signal and received MDP CD. (Pin 117 of IC701)

DESCRIPTION OF DATA PROCESSING

1. CD Data Processing Flow

Pickup

Unit

Motor

Drive

Generating

A/B/2C/E/F Signal

H8/3048

Buffer

CD Data Buffering

CXD1866Q CD-ROM Decoder and Host Interface

CXD 3011R-1

CD DSP

SSI3721 RF

Signal processing IC

CD TE/FE/SLED

Spindle Control

Command

Data Status

SDATA

CD DATA

CD RF

MA [0..8] MDB [0..F]

DATA [0..7] ADR [0..8]

SICLK SIXLT SIDAT SCLK

CD Data ECC

Receive the order from Host 2'nd ECC CD Data Buffering

Generating RF Signal Generating Tracking Error Generating Focusing Error

CD Servo Control CD Data Flow Control Host Command Receive or Data/Status Transfer

Error Correction Generating Header Sync Generating Subcode Sync

EFM Demodulation

2. DVD Data Processing Flow

DVD

Pickup

Unit

Motor

Drive

DVD

TE/FE/Sled/

Spindle control

Sled Control

CXD 3011R-1

CD DSP

H8/3048

Buffer

CXD1866Q

DVD DSP

Command

Data/ Status

DVD RF

DATA [0..7] ADR [0..8]

MA [0..8] MDB [0..F]

Generating

A/B/E/F Signal

SSI3721 RF

Signal processing IC

Generating RF Signal Generating Tracking Error Generating Focusing Error

Error Signal

Receive the Command from Host DVD Data Buffering Copy Protection Control

DVD Data Buffering

DVD Servo Control DVD Data Flow Control Host Command Receive or Data/Status transfer

EDC + ECC processing Generating DVD ID Sync

EFM Demodulation

CXD 1866Q

HOST DVD

PLAYER

(MPEG2 B/D)

H8/3048

Scrambled MPEG Data

Change the "KEY"

KEY Management Control

3. Copy Protection and Regional Code Management Block

Block Diagram

Brief Process

1. Regional Code for DVD Disc

Ð DVD-ROM drive transfers the regional code of the control data to host by the command of host, the DVD

player of host reads the regional code, and plays title in the case of allowed regional code only.

2. Management of DVD Disc for the scrambled of data

(1) DVD-ROM and DVD player of host generate the ÒKEY 1Ó respectively, transfer to opposite part, the

ÒKEY 2Ó is received, recognizes the data transfer or not with this value, and generates the bus key

encoded the data. (2) Encoded ÒDisc KeyÓ and ÒTitle KeyÓ host is transfer with the bus Key. (3) DVD player of host reads the key value, and uses the value to restore the scrambled data.

* Refer to the next page for the details.

4. About Prevention the DVD-ROM from to be copy

A data is able to encode and record in the disc, if a copyright holder wants to prevent the disc from copying.

In case of a disc enhanced movie of 3 titles......

DISC KEY (2048 Bytes) is used to encode the whole contents in the disc and TITLE KEY (5 Bytes) is used to encode the title respectively. So, the data is encoded and stored in a disc through the unknown algorithms with a disc key and title key. (At this time, the disc key and title key are stored in a disc.) ÉAs above, the disc is able to copy when the disc key and title key are opened. Then, ROM-DRIVE encodes the disc key and title key and transfers to MPEG2 board.

If you want to play the disc prevented from the copy......

First of all, ROM-DRIVE and MPEG-2 board identify with each other through the procedure as described below.

1. Drive and host gives and takes the ID of 2bit. This ID is AGID (Authentication Grant ID). The various decoder boards are attached to the host, in these, AGID sets the MPEG-2 board and drive.

2. After the AGID is set, MPEG-2 board generates the challenge key (10 Byte) and transfers to drive. The board and drive generate key 1 (5Byte) with the challenge key respectively. (Of course, the Algorithm generating the key 1 is not known.)

3. Compare with the generated key 1, if it corresponds each other, the first step of authentication is completed. This is a course to identify the MPEG-2 board with a drive.

4. The second step of authentication is a course to identify a drive with the MPEG-2 board. The dirve generates a challenge key and transfers it to the MPEG-2 board. The dirve and MPEG-2 board generate the key 2 (5Byte) with the challenge key, compare with each other, and if it corresponds and the secondary step of authentication is completed.

5. As above, the identification is completed.

6. The dirve and MPEG-2 board generate the Bus key with the key 1 and key 2 and own it.

7. Dirve encodes the disc key and title key with this Bus key and transfers to the MPEG-2 board.

8. The MPEG-2 board reads the encoded disc key and title key with the Bus key only.

9. MPEG-2 board lets data read from the drive to decode with the read disc key and title key and makes into the video signal by decoding.

ROM-DRIVE

AGID

HOST

MPEG-2 BOARD

Challenge key

encoded disc key, title key

+ 36 hidden pages