LG CED-8081B User manual

3
INTRODUCTION
FEATURES
1. General
1) Enhanced IDE interface.
2) Internal 5.25 inch, halfheight CD-R/RW Drive.
3) 2 Mbytes buffer memory.
4) Audio CD like tray loading of a disc without using a caddy.
5) Power loading and power ejecting of a disc. The disc can also be ejected manually.
6) Supports Power saving mode and Sleep mode.
7) Vertical and Horizontal operation.
2. Supported disc formats
1) Reads and writes data in each CD-ROM, CD-ROMXA, CD-I FMV, Video CD, and CD-EXTRA
2) Reads data in Photo CD (Single and Multi session).
3) Reads and writes standard CD-DA.
4) Reads and writes CD-R discs conforming to “Orange Book Part 2”.
5) Reads and writes CD-RW discs conforming to “Orange Book Parts 3”.
3. Supported write method
1) Disc at once (DAO), Session at once (SAO), Track at once (TAO), Variable packet, Fixed packet, and
Multi-session.
4. Performance
1) Random 100 ms average access time.
2) Max 4,800 kB/sec (Max 32X) Sustained Transfer rate.
3) Supports real time error correction and real time layered error correction at each speed.
4) Supports CD-R write operation at double speed, quadruple speed, and eight speed.
5) Supports CD-RW write operation at double speed and quadruple speed.
6) PIO Mode 4 & Multi DMA Mode 2 Support.
7) MPC-3 Spec compliant.
5. Audio
1) Output 16 bit digital data over ATA interface.
2) 4 Times Digital Filter for CD Audio
3) Software Volume Control
4) Equipped with audio line output and headphone jack for audio CD playback.
5) Front panel Volume Control for Headphone Output.
This service manual provides a variety of service
information.
It contains the mechanical structure of the CD-
R/RW Drive and the electronic circuits in
schematic form. This CD-R/RW Drive was
manufactured and assembled under our strict
quality control standards and meets or exceeds
industry specifications and standards.
This CD-R/RW drive is an internal drive unit
designed for use with IBM PC, HP Vectra, or
compatible computer. It can write as much as 650
Mbytes of digital data into CD-R/RW disc, and can
read as much as 650 Mbytes of digital data stored
in a CD-ROM, CD-R and CD-RW disc.
This CD-R/RW Drive can easily meet the
upcoming MPC level 3 specification, and its
Enhanced Intelligent Device Electronics (E-IDE)
and ATAPI interface allows Plug and play
integration in the majority of today’s PCs without
the need of an additional interface card.

4
SPECIFICATIONS
1. SYSTEM REQUIREMENTS
-CPU: IBM Compatible Pentium 233MHZ (or faster)
(For 8X Write speed, 266MHz or faster recommended.)
-32MB Memory or greater
2. SUPPORTING OPERATING SYSTEM
3. GENERAL
1) Host Interface.......................................................................................................................ATAPI compliant
2) Read Function
• Acceptable discs ...............................................................CD-ROM Mode1 (basic format), CD-ROM XA
CD-Audio
Mixed Mode (Audio and Data Combined)
Photo-CD (Single and Multi-Session)
CD-I Ready, Video CD
CD-Plus/CD-Extra,
CD-R (Conforming to “Orange Book Part2”)
CD-RW (Conforming to “Orange Book Part3”)
3) Write function
• Applied Format..................................................................CD-ROM Mode-1
CD-ROM XA
CD-Audio
Mixed Mode (Audio and Data Combined)
Video CD
CD-Plus/CD-Extra,
• Writing Method..................................................................Disc at once(DAO)
Session at once(SAO)
Track at once(TAO)
Variable packet writing
Fixed packet writing
Multi-session
4) Cache memory (R/W) .........................................................2 Mbyte
5) Disc diameter ......................................................................12 cm (8 cm Read only)
6) Data capacity (Yellow-Book)
• User Data/Block ................................................................2,048 bytes/block (Mode 1 & Mode 2 Form 1)
2,336 bytes/block (Mode 2)
2,324 bytes/block (Mode 2 Form 2)
2,352 bytes/block (CD-DA)
7) Rotational Speed
CD-Audio.............................................................................6x~15x(CAV) Approx.3000 rpm
CD-RW data ........................................................................8x~20x(CAV) Approx.4000 rpm
CD-ROM/CD-R data............................................................14x~32x(CAV) Approx. 7000 rpm
8) MTBF
• 120, 000 POH at an operating duty of 10% at room temperature.
4. DRIVE PERFORMANCE
1) Data Transfer Rate
* Sustained Data Transfer Rate ..........................................150 Kbytes/s (1x)
300 Kbytes/s (2x)
600 Kbytes/s (4x)
1,200 Kbytes/s (8x)
2,400 Kbytes/s (16x)
2,100 to 4,800 Kbytes/s 14 to 32x CAV
• DOS 3.1 or Higher
• Windows ‘95/’98/’2000
• OS/2 Warp (Ver 3.0)
• Solaris Ver 2.4 or higher
• Linux Slackware Ver 2.3
• Windows NT 4.0 or later

5
* Burst Data Transfer Rate (ATAPI) ....................................16.67 Mbytes/sec (PIO Mode 4)
16.67 Mbytes/sec (MULTI-DMA Mode 2)
2) Average Access Time
Random Access ..................................................................100 ms Typical (Max.32X) : INCLUDING LATENCY
3) Data Buffer Capacity ...........................................................2 Mbytes
5. POWER REQUIREMENTS
1) Voltage
+5 V DC with + 5% tolerance, less than 100 mVp-p Ripple voltage
+12 V DC with +5% tolerance, less than 100 mVp-p Ripple voltage
2) Current
• Hold Track State ...............................................................+5V DC 1.0A, +12 V DC 0.8A
• Seeking & Spin up ............................................................+5 V DC 1.2A, +12 V DC 1.0A
6. AUDIO PERFORMANCE
* CED-8081B FUNCTION TABLE
Item Typical Limit Test Signal Test Condition Note
Output Level 0.7 Vrms + 10 % 1KHz 0 dB No Filter at 47 kΩ
S/N 80 dB 75 dB 1KHz 0 dB with IHF-A + 20KHz LPF at 47kΩ
THD 0.2 % 0.25 % 1KHz 0 dB with IHF-A + 20KHz LPF at 47kΩ
Channel 70 dB 65 dB 1KHz 0 dB with IHF-A + 20KHz LPF at 47kΩ
Separation
Frequency + 2dB
Response
H/P
Output Level
AUDIO OUT
+3 dB 20Hz~18KHz 0 dB No Filter at 47 kΩ
0.6Vrms +20 % 1KHz 0dB No Filter H/P Volume MAX at 32 Ω
FFuunnttiioonnCCEEDD--88008811BB
•CD-R Writing speed 2x/4x/8x Data writing
•CD-RW Writing speed 2x/4x Data writing
•CD-ROM Reading speed 32x Data transfer
MMOODDEELL

LOCATION OF CUSTOMER CONTROLS
6
1. Disc tray
This is the tray for the disc. Place the disc on the
ejected disc tray, then lightly push the tray (or
push the eject button) and the CD will be loaded.
NOTE: Don’t pull out or push in the disc tray
forcibly. This might cause damage to the loading
section of the drive.
2. Stop/Eject button
This button is pressed to open the CD tray.
This button works only when power is supplied to
the drive.
If an Audio CD is playing, pressing this button will
stop it, and pressing it again will open the tray.
3. 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.
4. Emergency Eject Hole
Insert a paper clip here to eject the Disc tray
manually or when there is no power.
5. Volume control
This is used to adjust the output volume of the
headphone jack. It can’t be used to adjust the
output volume for the audio output connectors on
the rear panel.
NOTE : Turn the volume down before turning on
the power. Sudden loud noises can damage your
hearing.
6. Headphone jack
This jack is for connecting headphones or mini-
speakers.
7. Drive activity indicators
Two colored LEDs are used to indicate the
operation of CD-R/RW Drive.
(1) Read
The orange color is displayed when the spindle
motor begins the Spin up operation: accessing
data, reading data, playing Audio, and up loading
tray.
(2) Write
The green color is flashed during disc writing
sessions.
READ
READ
WRITE
WRITE
COMPACT
Headphone Jack
Volume
Control Drive Activity Indicators
Play/Skip Button
Stop/Eject Button
Disc Tray
Emergency Ejct Hole
Front Panel

7
1. Power Connector
Connects to the power supply (5-and 12-V DC) of
the host computer.
NOTE : Be careful to connect with the proper
polarity. Connecting the wrong way may damage
the system (and is not guaranteed). Usually this
connector can only be attached one-way.
2. IDE Interface Connector
Connect to the IDE (Integrated Device
Electronics) Interface using a 40-pin flat IDE
cable.
NOTE : Do not connect or disconnect the cable
when the power is on, as this could cause a short
circuit and damage the system. Always turn the
power OFF when connecting or disconnecting the
cable.
3. Jumper Connector
This jumper determines whether the drive is
configured as a master or slave. Changing the
master-slave configuration takes effect after
power-on reset.
4. Analog Audio Output Connector
Provides output to a sound card (analog signal).
Generally you need this to play a regular audio
CD.
5. Digital Audio Output Connector
Provides output to a sound card (digital signal).
DIGITAL ANALOG
INTERFACE POWER
DRCS M
SLA
GLG39
1
+5 +12
GND
40
2
AUDIO AUDIO
Digital Audio Output
Connector
Jumper Connector
Analog Audio Output Connector IDE Interface Connector
Power Connector
Rear Panel

1. CABINET and CIRCUIT BOARD
DISASSEMBLY
1-1. Bottom Chassis
A. Release 4 screws (A) and remove the Bottom Chassis
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 2 hooks (a) and remove the CD Tray
drawing forward.
C. Remove the Main Circuit Board in the direction of
arrow (5).
D. At this time, be careful not to damage the 4
connectors, are positioned at left side, of the Main
Circuit Board.
2. MECHANISM ASSY DISASSEMBLY
2-1. Pick-up Unit
A. Release 2 screws (B).
B. Separate the Pick-up Unit in the direction of arrow (6).
(4)
(5)
Main
Circuit Board
Cabinet
Hooks (a)
(A)
(A) (A)
(A)
(1)
Bottom Chassis
(2)
(3)
Tray Door
CD Tray
Front Bezel Assy
Emergency Eject Hole
Stoppers
Fig. 1-1
Fig. 1-2
DISASSEMBLY
8
Fig. 1-3
Mechanism Assy
Pick-up Unit
(B)
(B)
(6)
Fig. 1-4

2-2. Pick-up
A. Release 1 screw (C) and remove the Pick-up.
2-3. Sled Motor Assy
A. Release 2 screws (D),(E) and remove the Sled
Motor Assy.
(D) (E)
Sled Motor Assy
Pick-up Unit
Pick-up
(C)
Fig. 1-5
9
Fig. 1-6

TROUBLESHOOTING GUIDE
Are the pin 41
and 44 of PN201 +12V and +5V
respectively after the power
cable connecting?
Reset or Power Check.
• Check the power(12V, 5V) short.
• Check PC power cable.
• Repair the PC power supply.
• Check the IC101(RESET IC).
• Check the IC102(PQ1U331), IC201
(OTI-9790), IC301(MB90F476)
Does the pin 1
of IC101 change 0V to 5V at the
power supply initial input mode?
• Is the pin 16 of IC401 4.0V?
• Is the pin 31 of IC401 2.0V?
• Is the pin 5 of IC102 3.3V?
• Is the pin 7 of IC514 2.5V?
• Is the pin 1 and 2 of IC514 2.0V?
• Is the pin 1 of IC512 8.0V?
NO
NO
YES
YES
YES
YES
YES
49
Are the X201 and X301 oscillating?
• Check the X201, X301.
• Check the IC201, IC301.
NO
• Check the IC401(OTI9071).
• Check the IC102(PQ1U331).
NO
Check the IC514(NJM3414).
• Check the IC512(NJM7808).
NO
NO
Check it after connecting the power cable
only on interface cable for NO Reset or
Power ON.
YES
OK

50
System Check.
Go to “Tray operating is abnormal”
Load tray without inserting disc.
NO
Does Tray operate normally?
Does Pick-up move to inside?
Does Spindle Motor
rotate in a moment?
Does Laser turn on?
After eject tray, Inset CD-ROM Disc
and reloading.
Does Disc stop?
Does Disc rotate
continuously as Disc recognition is
abnormal?
After eject tray, Inset CD-R Blank Disc
and reloading.
Does Disc rotate
continuously as Disc recognition is
abnormal?
Does Disc stop?
Go to “Sled operating is abnormal”
Go to “Spindle operating is
abnormal”
Go to “Laser is abnormal”
Go to “Spindle control is abnormal 1”
Go to “Spindle control is abnormal 2”
Go to “Spindle control is abnormal3”
Go to “Disc recognition is abnormal”
NO
NO
NO
YES
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
Does Lens move
Up/Down?
Go to “Focus Actuator operating is
abnormal”
NO
YES
OK

51
Is the input voltage
0V at IC301 pin 10 when push the
SW802?
Tray operating is abnormal.
Is there Tray
drive voltage output?
(IC501 pin 15, 16)
Is TRAY_MUTE signal “L”?
(IC501 pin 20)
• Check the connection of IC301 pin 10.
• Replace the SW802(Eject s/w)
(Tray open/close doesn’t work)
NO
• Check the connection of IC301 pin 18.
• Replace the IC301.
NO
NO
• Check the Tray Connector(PN301).
• Check the Motor Line and Motor.
YES
Is there Tray control signal input?
(IC501 pin 26)
• Check the connection of IC409 pin 12.
• Replace the IC409(BU2500FU).
• Check the communication line between
IC409 and IC301(MICOM).
NO
YES
YES YES
When PN301
is open, Is there Tray drive
signal output?
• Replace the IC501(BA5983FM).
NO
YES

52
Is there Sled
control signal output?
(IC409 pin 7)
Sled operating is abnormal.
Replace the IC501 (BA5983).
Replace the IC508 (BU4053).
NO
Replace the IC409.
NO
Is Act_Mute signal ‘L’?
(IC501 pin 9)
•Check the connction of IC502 pin 17.
•Replace the IC502(BA5925FA)
Check the connection of IC301
pin 13.
Is there
HALL/SLDOUT signal
input? (IC301 pin 39)
Is there
SLED FG signal input?
(IC301 pin 63)
Check the IC502(BA5925).
NO
Check the communication line
between IC409 and IC301.
NO
NO
YES
YES
YES
YES
Is there
HALL 1 signal input?
(IC508 pin 3)
NO
• Check the Connector(PN501).
• Replace the SLED Motor.
NO
Is there Sled drive voltage
input? (IC501 pin 23)
YES
NO
Is there
Sled drive voltage output?
(IC501 pin 17, 18)
YES
YES
OK

53
Is there
Spindle control signal input?
(IC510 pin 22)
Spindle operating is abnormal
• Check the connection of IC201 pin 2.
• Replace the IC201(OTI-9790).
Is there
DMO signal input?
(IC509 pin 5)
Replace the IC508(BU4053).
Is there
Spindle drive voltage output?
(IC510 pin 2, 4, 7)
• Check the Spindle
Connector(PN502)
• Replace the Spindle Motor.
NO
NO
YES
Is SPNON signal “H”?
(IC510 pin 23)
NO
YES
YES YES
NO
• Replace the IC509(NJM3404).
• Check the connection of IC301 pin 14.
• Replace the IC301(MICOM).
Is SBRK signal “L”?
(IC510 pin 18)
NO
YES
• Check the connection of IC301 pin 30.
• Replace the IC301(MICOM).
Is there a
SPNFG signal input?
(IC301 pin 62, IC201 pin 7)
NO
YES
• Check the connection of IC510 pin 19.
• Replace the IC510(BA6664FM).
Is there Spindle
control signal output?
(IC509 pin 7)
YES
NO
OK

54
Focus Actuator operating is
abnormal
Is there Focus
Search control signal input?
(IC501 pin 3)
Is Act_Mute signal “L”?
(IC501 pin 9)
• Replace the IC501(BA5983).
• Check the connection of PN401 pin 1, 4.
• Check the Pick-up Connector(PN401).
• Check the connection of IC301 pin
3.
• Replace the IC301(MICOM).
NO
YES
• Replace the Pick-Up.
Is there Focus
Search drive voltage output?
(IC501 pin 13,14)
NO
• Check the connection of IC201 pin 207.
• Check the communication line between
IC201 and IC301.
• Replace the IC201 (OTI-9790)
YES
NO
YES
Spindle control is abnormal 1
(CD-ROM Disc)
Does FOCUS Servo
operate normally?
Is there a output normally?
(IC401 pin 34, 33)
• Replace the IC403(KM4200).
Go to “Spindle operating is
abnormal”
• Replace the IC401(OTI9071).
NO
YES
Is there RFAC signal input?
(IC201 pin 163)
NO
• Go to “Focus Servo is unstable”
YES
NO
YES

55
Is there RRF signal input?
(IC403 pin 3, 2)
Spindle control is abnormal 2
(CD-ROM Disc)
Go to “RF output is abnormal”
Is there EFM signal output?
(IC403 pin 7)
YES
YES
NO
Replace the IC403(KM4200).
NO
Does Tracking Servo
operate normally?
YES
Go to “Track Servo is unstable”
Go to “Disc recognition is abnormal”
NO
Is there WBLIN signal input?
(IC201 pin 132)
Spindle control is abnormal 3
Go to “RF output is abnormal”
Is there ATG signal output?
(IC401 pin 41)
YES YES
NO
Replace the IC401(OTI9071).
NO
Is there DMO signal output?
(IC202 pin 2)
YES
Replace the IC201(OTI-9790).
Go to “Spindle operating is abnormal”
NO

56
Is there CDR/RW signal input
normally? (IC601 pin 33)
Go to “Track Servo is unstable”
Disc recognition is abnormal
Replace IC301 (MICOM)
Is there RECD1,
RECD2 signal output normally?
(IC401 pin 61, 62)
Go to “RF output is abnormal”
YES
YES
NO NO
Is there
PICK UP (A, B, C, D)
output normally?
(PN401 pin 8, 9, 14, 15)
RF output is abnormal
• Check the PICK UP FFC.
• Replace the PICK UP. Go to “Laser is abnormal”
YES
Is RRF
signal output normal?
(IC401 pin 89)
• First Recognition try: Over 1.04 Vpp
• Second Recognition try:
Over 0.3 Vpp
YES
NO
• Check the connection between
PN401 and IC401.
• Replace the IC401(OTI9071).
No
OK

57
Focus Servo is unstable
Is FE signal
output normal in Focusing
Up/Down?
(IC401 pin 30)
YES
Check the IC401(OTI9071).
Go to “RF output is abnormal”
Go to “Focus Actuator
operating is abnormal”
NO
Track Servo is unstable
Is TE signal
output normal in Focusing
ON and Tracking OFF?
(IC401 pin 28)
YES
• Check the PICK UP FFC.
• Replace the PICK UP.
Check the IC401(OTI9071).
Go to “RF output is abnormal”
Check the IC404 (NJM3403)
NO
Is TE signal
input normal in Focusing
ON and Tracking OFF?
(IC201 pin 198)
NO
Replace the IC201(OTI-9790).
Check the Driver IC(IC501) and
P/U referring to “Focus Actuator
operating is abnormal”.
Is there TAO
signal output in Tracking ON?
(IC201 pin 208)
NO
Is PICK UP
(E, F, G, H) output normal?
(PN401 pin 16, 7, 13, 10)
YES
YES
YES
YES
NO
Is FAQ signal
output normal in Focusing
Up/Down?
(IC201 pin 207)
Replace the IC201(OTI-9790)
NO
YES

58
Is EEPROM Data valid?
Execute ‘B.Calibration Data’ of
‘How to use Test Tool (Dragon)’
Execute ‘D.LD Inspection’ of ‘How
to use Test Tool(Dragon)’
YES
NO
OK?
NO
Laser is abnormal
OFF LEVEL NG?
VRDC NG?
G
E
Normal
F
NO
Execute ‘C.LD Power Setup’ of
‘How to use Test Tool(Dragon)’
NO
YES
NO
VWDC1 NG?
YES
YES
YES

59
LD CHECK (Not Read)
Execute ‘E. LD On’ of ‘How to
use Test Tool (Dragon) : ‘VRDC
Loop [Read Mode]’
PN401 Pin 32(ENBL)=H?
Normal
NO
E
• Check the connection of IC601 pin 20.
• Check and replace the IC601(Asic).
YES
IC401 Pin 10(RREF):
CED-8081B:3.1+/-0.2V?
NO
• Check the connection of IC409 Pin 18,
IC410 Pin 1, 2, 3.
• Check and replace the IC409(DAC).
YES
IC401 Pin 4(FPDO):
2.4+/-0.3V?
NO
• Check the connection of PN401 pin 19.
• Check and replace the PN401, PICK UP.
YES
PN401 Pin 25(VRDC) :
CED-8081B:0.9+0.5V?
NO
• Check the connection of IC401 pin 12.
• Check and replace the IC401.
Execute ‘D. LD Inspection’ of ‘How to
use Test Tool(Dragon)’
Check the P/U connector and then
replace the P/U.
YES
YES
VRDC NG?
NO

• Check the connector of IC601 pin 20.
• Check and replace the IC601(Asic).
PN401 Pin 32(ENAB) = ‘H’?
F
Execute ‘E. LD On’ of ‘How to
use Test Tool(Dragon)’:
‘VWDC-1 Loop’
PN401 Pin 27 (VWDC1) :
1.2+/-0.8V?
• Check the connection of IC401 pin 6.
• Check the connection of IC409 pin 9.
• Check and replace the IC401, IC409.
Check the P/U connector and
replace the P/U.
Execute ‘D. LD Inspection’ of ‘How to
use Test Tool(Dragon)’
YES
YES
YES
NO
• Check the connection of IC601 pin 18,29 and 34.
• Check and replace the IC601(Asic).
PN401 Pin 31(W/XR) = ‘H’?
YES
NO
• Check the connection of IC409 pin 4.
• Check and replace the IC409(DAC).
IC401 Pin 5(WREF) :
3.1+/-0.2V?
YES
NO
• Check the connection of PN401 pin 19.
• Check and replace the PN401, PICK UP.
IC401 Pin 4(FPDO) :
2.4+/-0.3V?
YES
NO
NO
NO
VWDC NG?
Normal
LD CHECK (Not Recorded)
60

61
• Check the connection of IC601 pin 21 and 30.
• Check and replace the IC601(Asic).
• Check the connection of IC601 pin 18 and 34.
• Check and replace the IC601(Asic).
• Check the connection of IC409 pin 19.
• Check and replace the IC409(DAC).
P/N401 Pin 30(ODON) = ‘H’?
G
Execute ‘E.LD On’ of ‘How to
use Test Tool(Dragon)’ :
‘VWDC-2’
PN401 Pin 31(W/XR) = ‘H’?
PN401 Pin 26(VWDC2) :
CED-8081B:3.4+0.4V?
Check the P/U connector and
replace the P/U.
YES
YES
YES
YES
NO
NO
NO