Sony CDU31A Series User manual

CD-ROM DRIVE UNIT
CDU31A-O 1
CDU31A-02
CDU-541-51
CDU-541-81
CDU31A-GW
CDU31A-L L
SONY:
SERVICE MANUAL

SECTION 4 PARTS REPLACEMENT ······························································································· 4-1
4-1
EASY REFERENCE CHART ·························································································· 4-1
4-2 BOTTOM PLATE REPLACEMENT ················································································· 4-2
4-3 FRONT PANEL ASS'Y REPLACEMENT
········································································· 4-2
4-4
.. MA-1/MA-2 MOUNTED BOARD REPLACEMENT ············································ ··············· 4-3
4-5 OPTICAL DEVICE REPLACEMENT ··································
··· ············· ··· ···· ···· ·················· 4-3
SECTION 5 CHECK AND ADJUSTMENT ························································································· 5-1
5-1
ELECTRICAL ADJUSTMENT ··········· ··· ········· ······ ·· ··· ···· ···· ····· ········· ································ 5-1
5-1-1 Special Tools and Measuring Equipment ·········································································· 5-1
5-1-2 Pre-Setting ·················· ··· · ··· ·········· ····· ················ ···· ························· ··· ······················· 5-1
5-1-3 EF Balance ····························································································•·················· 5-3
5-1-4 Focus Servo Loop Gain ··········································•················
·• ·············•···················· 5-4
5-1-5 Tracking Servo Loop Gain
··························································································· 5-5
5-1-6 Focus Bias ······
··· · ··· ··· ··· ········· ···· ······················ ··· ··········· ······ ······· ····· ···· ···· ················· 5-6
5-2 RF LEVEL (LASER POWER) AND LASER CURRENT
······················································ 5-7
5-2-1 Special Tools and Measuring Equipment
·········································································· 5-7
5-2-2 Measurement ·········
···· ··· ··· ·· ······ ··· ···· ····•··•···· ········· ··· ····· ······ ··············· ···•· ······ ········· ···· 5-7
5-3 OPTICAL DEVICE CLEANING ·
···· ·················· ·········· ··· ····· · ····· ··········· ······· ······ ···· ·· ······· ·· 5-8
5-3-1 Special Tools and Measuring Equipment ·········································································· 5-8
5-3-2 Cleaning with lens cleaner ·
···· ···· ···· ·· ······· ················· ··· ························· ········ ·········· ······· 5-8
SECTION 6 EXPLODED VIEWS AND LIST ····················································································· 6-1,..
6-1 MECHANICAL ASS'Y LOCATION ················································································· 6-1
6-1-1 Overall Ass'y ········•··································································································· 6-1
6-1-2 Packing Material ·····················•·················•·················································•·············· 6-5
6-2 DIAGRAMS
················•···········································.·······································•············· 6-6
6-3 PART LAYOUT AND CIRCUIT DIAGRAM
···································································· 6-8
6-3-1 Parts Layout on MA- I/MA-2 Mounted Board · ···· · ····· ···· ··· ······· ···· ··········· ···· ·· ······· · ······· ······· 6-8
6-3-2 Circuit Diagram on MA-I Mounted Board
····························•··················•·•············•···•····· 6-17
6-3-3 Circuit Diagram on MA-2 Mounted Board
·················•···············••················•···················· 6-25
6-4 ELECTRIC PARTS LIST
•····························•································································· 6-33
SECTION 7 SEMICONDUCTORS PIN ASSIGNMENT ········································································ 7-1
II

Note: Note on Repairing Optical Device (KSM-360ABM)
or Base Unit.
When opening or repairing the unit, grounding is required
to prevent damage caused
by static electricity and is as
follow:
I. G1"9unding for the human body
Be su.:C to wear a wrist-strap for grounding (with
impedance lower than
IO" Q) whose other end is
ground. The strap works to drain away static electricity
build-up on the human body.
x
Optical Device
4. Afterconnection to the MA-l/MA-2 Mounted Board,
to open the LO short land, remove the soldering
quickly with a soldering iron whose insulation
resistance
is larger than I0 M Q.
LD Short land
2. Grounding for the work table
Be sure to lay a conductive sheet (with impedance
lower than
Io• Q ) on the table, such as a sheet of
copper, which is ground.
3. As static electricity build-up on clothes is not drained
away,
be careful not to let yourclothes touch the unit.
(D Wrist.Strap
forgrounding
Conductive aheet
orcopper plate

SECTION 1
INTRODUCTION
1·1 CONFIGURATION OF SERVICE MANUAL
This manual is a maintenance guide for model CDU31A
series.
SECTION 2 describes disks and tools necessary for
maintenance.
SECTION 3 provides fault diagnostic procedures that may
require spare pans
or some adjustments.
The overall check after removal and adjustments will be
included
in this section.
SECTION 4 and 5 cover parts replacement and
adjustments, respectively.
SECTION 6 consist of circuit diagrams, ass'y drawings,
and parts lists.
1-2 CAUTION
Caution: As the laser beam used in this drive is harmful to
the eyes, do not attempt to disassemble the
cabinet. Refer servicing to qualified personnel
only.
Caution: This CD-ROM drive is classified as a CLASS I
LASER product. The CLASS I LASER
PRODUCT label
is located on the case.
1 ·3 PRECAUTIONS
1-3-1 Installation
a. Avoid placing the drive in a location subject to:
high humidity
high temperature
excessive dust
mechanical vibration
direct sunlight
b. This drive can be used horizontally only.
1-1
1-3-2 Operation
a. Do not move the drive while it is operating. Doing so
may cause a malfunction to occur.
b. Avoid exposing the drive to sudden changes in
temperature. This may cause condensation to collect
inside the drive. If
the ambient temperature should
suddenly rise while the drive
is turned on, wait at least
one hour before turning off the drive. Ifyou attempt to
operate the drive immediately after a sudden increase
in temperature, a malfunction may occur during
reading.
1-3-3 Transportation
a. Keep the original packing materials to facilitate
transporting the drive.
b. Always remove the disc before moving the drive.
After removing the drive
from the computer, repack
the drive into its original packing.
1-4 INTRODUCTION
a. CDU31A series is a drive unit for CD-ROM (Compact
Disc Read-Only Memory) discs, which store
as much
as 540 Mbytes of digital data.
b. The drive unit offers the following features:
-5.25 inch half-height drive form factor.
-Audio output to enable Audio CD playback.
-Audio channel selectable by software (stereo,
monaural, reverse, etc.)
-Fast access time providing high-speed read
operation.
-Real time layered error correction.
-Emergency eject function for manual disc
ejection.
-CD-ROM XA, CD Bridge disc and CD-I disc
play.
Software requirement:
-To read data reading of the data stored on a disc,
install the appropriate application software.
-To read data from CD-ROM discs with the High
Sierra Group (HSG) or IS0-9660 logical format,
you can use Sony OPA-474 series MS-DOS
CD-ROM Extensions. This software extends
MS-DOS*. It is designed for use on IBM
PC/ATs**
* MS-DOS
is registered trademark of Microsoft
Corporation.
** IBM PC, PC/ST, and PC/AT are registered trademarks
of International Business Machines Corporation.

1-2

SECTION 2
TOOLS AND MEASURING INSTRUMENTS
2·1 GENERAL AND SPECIAL TOOL LIST
The tools and measuring instruments for perfonning
maintenance on the CDU31 A series are listed below.
2-1-1 General Tools
©Driver 2.6mm
Tweezers
Round Nose Plier
Cutter
PC-DOS Disk
Soldering Iron (20W)
Desoldering Metal Braid (Solder Wick)
Tester (DRM)
Power Supply± 12V (min. 0.SA)
BNC-BNC Cable (I .Sm)
SONY Test Disc (YEDS-18)
SONY Parts No.
(7-700-749-03)
(7-700-7S3-02)
(7-700-7S7-0I)
(7-700-7S8-02)
(3-702-101-01)
This disc is used to adjust EF Balance.
2-1-2 Special Tools
IBM PS/2 System
PS/2 Model 30
or equivalent (640 k Byte RAM, 3.S"
FDD, Video RAM-CGA or Higher)
OPA-4741 System
CDB-334 Interface Card
Connection
SOP Cable
SOP Connector Ass'y
DC Power supply
Headphone (Stereo type/mini jack)
SONY Test Disc (YHDS-100)
SONY Test Disc (YHDS-SO)
Power Cord
ATP SLCD disk (0R-D900)
This Disk is used for Final Check.
BNC (one-end) Cable
SIA Attachment Tool
SLCD Test disk (0R-D901)
SRV SLCD Test disk (0R-D914)
Torque Driver two Bits
Fixture CDI
Line Out Relay Ass'y
Active Speaker
2-1-3 Measuring Equipment
(1-696-776-11)
(A-467S-38S-A)
(1-413-362-12)
(1-SS9-370-I
I)
(8-969-923-00)
(J-907-202-0A)
(J-907-S03-0A)
(8-969-923-01)
(8-969-923-14)
(J-623-807-0A)
(J-907-203-0A)
(A-467S-386-A)
Oscilloscope Dual Trace 20MHz (probe xlO)
Frequency Response Analyzer (recommend SOIOA (NF
Electronic Instruments))
DC Volt Meter (min. IOmA)
2-1-4 Expendable and Chemical Supplies
Cleaning Liquid Lens (J-2SO-IOO-OA)
Molykote Grease (EM-30L) (4-918-64S-OI)
Cotton swab (200 pieces) (7-740-900-6S)
2-1

2-2 SPECIAL TOOLS
2-2-1 S/A Attachment Tool
This tool is used to measure the open loop characteristics of
the Focusingffracking servo
of the CD-ROM drive without
cutting its servo
~ircuit.
(I) S/A Attachment Tool Configuration (Refer to Fig. 2-2
(a))
(2) S/A Attachment Tool Function
Terminals
8 FB IN ... This terminal is connected to the BNC
(one end) Cable which leads from the CD-ROM
drive. (FE3
or TE3 test lands)
• FB OUT; .. This terminal is connected to the BNC
Cable (application) which leads from CH-I
channel
of the analyzer.
8 ERR OUT... This terminal is connected to the
BNC Cable (application) which leads from CH-2
channel
of the analyzer or connected oscilloscope
probe.
8 ERR IN/DIS OUT... This terminal is connected to
the BNC (one end) Cable which leads from
CD-ROM drive. (FE2
or TE2 test lands)
8 DIS IN ...'This terminal is connected to the BNC
Cable (application) which leads from OSC
channel of the analyzer.
(i) +12V/ -12V/ GND... These terminals have a
supplied voltage of +12V/ -
12V from power
supply.
Switch
0 SI... This switch is to stan the test.
(3) S/A Attachment Tool Circuit Diagram (Refer to Fig.
2-2 (b))
Fig. 2-2 (a) SIA Attachment Tool Configuration
2-2

DISTURBANCE OllT
/ERR INPUT
to from FE3 or TE3
DISTURBANCE
ON/Qff
Fig. 2-2(b) SIA Attachment Tool
2-3
DISTURBANCE INPUT
from OSC of NF501 OAnalyzer
(or RC Oscillator)
+12V
.... ----1-----0 +12V
.r-F-::
12V

2-2-2 Fixture CDI
(I) Fixture CD! Configuration (Refer to Fig. 2-2 (c))
(2) Fixture CD! Function
Switch
8 SI ... This switch is used for adjustment.
Fixture CD1
Fig. 2-2(c) Fixture CD1 Configuration
2-4

2·3 PS/2 SYSTEM SETTING AND
CONFIGURATION a. Install the SONY CDB-334 interface card
in the PS/2
system.
2-3-1 Set up PS/2 System
Note: Make sure that the PC-DOS has been installed on
the hard disk.
2-3-2 System configuration
ATPSLCD Test Disk
(for
ATP)
SLCD Test Disk
(for Outgoing Test)
SRV SLCD Disk
(for Function Check/
Adjustment)
Headphone
~~
SONY Test Disc (YHDS-100) (for ATP)
SONY Test Disc (YHDS-50) (for Outgoing Test)
SONY Test Disc (YEDS-18) (forAdjustment)
Fig. 2-2 ATP/Function check/Outgoing Test/Adjustment System
2-5
Connection 50P Cable
(1-696-776-11)