Sony DEJ-750 Service manual

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

SERVICE MANUAL

Ver 1.0 2002.02

Photo : D-EJ755

US Model

D-EJ756CK/EJ758CK

Canadian Model

UK Model

D-EJ751/EJ755/EJ758CK

AEP Model

D-EJ750/EJ751/EJ753/EJ755/EJ758CK

Australian Model

E Model

D-EJ751/EJ758CK

Chinese Model

D-EJ751

Model Name Using Similar Mechanism D-E350 CD Mechanism Type CDM-3125ER Optical Pick-up Type DAX-25E

System

Compact disc digital audio system

Laser diode properties

Material: GaAlAs Wavelength : λ = 780 nm Emission duration : Continuous Laser output : Less than 44.6 µW (This output is the value measured at a distance of 200 mm from the objective lens surface on the optical pick-up block with 7 mm aperture.)

D-A conversion

1-bit quartz time-axis control

Frequency response

20 - 20 000 Hz

Output (at 4.5 V input level)

Line output (stereo minijack) Output level 0.7 V rms at 47 k Recommended load impedance over 10 k Headphones (stereo minijack) Approx.5 mW + Approx. 5 mW at 16 Ω (Approx. 0.5 mW + Approx. 0.5 mW at 16 Ω)* *For the customers in France

Power requirements

For the area code of the model you purchased, check the upper left side of the bar code on the package.

• Two Sony NC-WMAA rechargeable batteries: 2.4 V DC

• Sony NH-WM2AA rechargeable batteries:

2.4 V DC

• Two LR6 (size AA) batteries: 3 V DC

• AC power adaptor (DC IN 4.5 V jack): US, CND, C&SA, MX model: 120 V, 60 Hz AEP, FR, G, EE, E13 mode : 220 - 230 V, 50/60 Hz UK model: 230 - 240 V, 50 Hz AUS model: 240 V, 50 Hz CH model: 220 V, 50 Hz

dB (measured by JEITA CP-307)

–2

SPECIFICATIONS

Battery life* (approx. hours)

(When you use the CD player on a flat and stable surface.) Playing time varies depending on how the CD player is used.

When using G-PROTECTION function

Two NC-WMAA 12 10 (charged for about 3 hours**) NH-WM2AA 25 22 (charged for about 5 hours**) Two Sony alkaline 48 38 batteries LR6(SG) (produced in Japan)

* Measured value by the standard of JEITA (Japan

Electronics and Information Technology Industries Association).

** Charging time varies depending on how the

rechargeable battery is used.

Operating temperature

5°C - 35°C (41°F - 95°F)

Dimensions (w/h/d) (excluding projecting parts and controls)

Approx. 135.5 × 29.2 × 137.4 mm (5 3 ⁄ 8 × 1 3 ⁄

Mass (excluding accessories)

Approx. 185 g (6.6 oz.)

Design and specifications are subject to change without notice.

× 5

⁄ 2 in.)

on off

Accessories Supplied accessories

For the area code of the location in which you purchased the CD player, check the upper left side of the bar code on the package.

AC power adaptor (1) Headphones/earphones

with remote control (1) Headphones/

earphones (1) Rechargeable

batteries (2) Battery carrying case (1)

* 1 Supplied with MX models * 2 Not supplied with MX models D-EJ756CK/EJ758CK AC power adaptor (1) Headphones/earphones (1) Rotary commander (1) Car battery cord (1) Car connecting pack (1) Velcro tape for the CD player (4) Velcro tape for the rotary commander (2) Hand strap (1)

D-EJ751

D-EJ750

– –

–– ––

D-EJ755

D-EJ753

aaa

–

PORTABLE CD PLAYER

9-873-580-01

Sony Corporation

Personal Audio Company Pubulished by Sony Engineering Corporation

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

TABLE OF CONTENTS

• Abbreviation AUS : Australian FR : French EE : East European CND : Canadian CH : Chinese MX : Mexico C&SA : Central and South America E13 : AC220-230V area model

DANGER

Invisible laser radiation when open and interlock failed or defeated. Avoid direct exposure to beam.

CAUTION

Use of controls or adjustments or performance of procedures other than those specified herein may result in hazardous radiation exposure.

Laser component in this product is capable of emitting radiation exceeding the limit for Class 1.

This Compact Disc player is classified as a CLASS 1 LASER product. The CLASS 1 LASER PRODUCT label is located on the rear exterior.

Flexible Circuit Board Repairing

• Keep the temperature of the soldering iron around 270°C during

repairing.

• Do not touch the soldering iron on the same conductor of the circuit board (within 3 times).

• Be careful not to apply force on the conductor when soldering or unsoldering.

Notes on chip component replacement

• Never reuse a disconnected chip component.

• Notice that the minus side of a tantalum capacitor may be dam-

aged by heat.

Specifications ............................................................................ 1

1. SERVICING NOTES................................................... 3

2. GENERAL

Locating the Controls......................................................... 3

3. DISASSEMBLY

3-1. Upper Lid Sub ASSY, Cabinet (Front) Sub ASSY..... 4

3-2. MD ASSY, Main Board .............................................. 5

3-3. “Motor ASSY, Turn Table (Spindle) (M901)”............ 5

3-4. “Motor ASSY (Sled) (M902)”,

Optical Pick-up (DAX-25E) ...................................... 6

4. ELECTRICAL ADJUSTMENS ............................... 7

5. DIAGRAMS

5-1. Explanation of IC Terminals....................................... 8

5-2. Block Diagram.......................................................... 13

5-3. Printed Wiring Boards .............................................. 14

5-4. Schematic Diagram –MAIN SECTION (1/3)– ....... 15

5-5. Schematic Diagram –MAIN SECTION (2/3)– ....... 16

5-6. Schematic Diagram –MAIN SECTION (3/3)– ....... 17

6. EXPLODED VIEWS

6-1. Upper Lid Section..................................................... 19

6-2. Cabinet Section......................................................... 20

6-3. Optical pick-up Section (CDM-3125ER) ................. 21

7. ELECTRICAL PARTS LIST................................... 22

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE WITH MARK 0 ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY.

ATTENTION AU COMPOSANT AYANT RAPPORT

LES COMPOSANTS IDENTIFIÉS P AR UNE MARQUE 0 SUR LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT . NE REMPLACER CES COMPOSANTS QUE PAR DES PIÈCES SONY DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.

À LA SÉCURITÉ!

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

SECTION 1

SERVICING NOTES

NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT

The laser diode in the optical pick-up block may suffer electrostatic breakdown because of the potential difference generated by the charged electrostatic load, etc. on clothing and the human body. During repair, pay attention to electrostatic breakdown and also use the procedure in the printed matter which is included in the repair parts. The flexible board is easily damaged and should be handled with care.

NOTES ON LASER DIODE EMISSION CHECK

The laser beam on this model is concentrated so as to be focused on the disc reflective surface by the objective lens in the optical pick-up block. Therefore, when checking the laser diode emission, observe from more than 30cm away from the objective lens.

Before Replacing the Optical pick-up Block

Please be sure to check thoroughly the parameters as per the “Optical pick-up Block Checking Procedure” (Part No. : 9-960-027-11) issued separately before replacing the optical Pick-up block. Note and specifications required to check are given below.

• FOK output : IC601 yg pin When checking FOK, remove the lead wire to disc motor.

• RF signal P-to-P value : 0.45 to 0.65Vp-p

Laser Diode Checking Methods

During normal operation of the equipment, emission of the laser diode is prohibited unless the upper panel is closed while turning ON the S801 (push switch type). The following two checking methods for the laser diode are operable.

Method : Emission of the laser diode is visually checked.

1. Open the upper lid.

2. Push the S801 as shown in Fig. 1 .

3. Check the object lens for confirming normal emission of the laser diode. If not emitting, there is a trouble in the automatic power control circuit or the optical pick-up. During normal operation, the laser diode is turned ON about 2.5 seconds for focus searching.

S801

LOCA TING THE CONTROLS

CD player (front)

1 PLAY MODE

button

2 SOUND button

VOL (volume) +*

4 'm (AMS/

search) button

5 VOL (volume) –

button

6 X (pause) button

7 x (stop)/CHG (charge)

button

8qjN* (play)/>

(AMS/search) button

SECTION 2

GENERAL

Fig.1 Method to push S801

This section is extracted from instruction manual.

9 DC IN 4.5 V (external

power input) jack

0 Strap holes qa Display

qs REPEAT/ENTER

button

qd HOLD switch

qf OPEN switch

qg LINE OUT

qh i (headphones)

CD player (inside)

G-PROTECTION switch

*The button has a tactile dot.

qk Battery compartment

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

SECTION 3

DISASSEMBLY

The equipment can be removed using the following procedure.

MD ASSY “Motor ASSY, turn table (spindle) (M901)”, Optical pick-up (DAX-25E),

“Motor ASSY (Sled) (M902)”

Set

Upper lid sub ASSY, Cabinet (front) sub ASSY

Main board

Note : Follow the disassembly procedure in the numerical order given.

3-1. UPPER LID SUB ASSY, CABINET (FRONT) SUB ASSY

Upper lid sub ASSY

6 Switch unit flexible board

7 Six screws (B2)

5 Connector cover

Cabinet (front) sub ASSY

1 Open

8 Claw

3 Spring (full

open), left

2 Spring (full open), right

8 Claw

• CAUTION DURING ASSSEMBLY

CN801

6 Spring

(full open), left

1 Switch unit

flexible board

8 Claw

• "SPRING FULL OPEN" REMOVAL

Cabinet (rear) sub ASSY

3 Spring (full open), right

• "SPRING FULL OPEN" INSTALL

Insert the point

2Push in

3-2. MD ASSY, MAIN BOARD

1 CN501

2 CN502 (black)

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

MD ASSY

3 CN503 (white)

3-3. “MO TOR ASSY , TURN T ABLE (SPINDLE) (M901)”

Main board

Cabinet (rear) sub ASS

1 Screws (B1.7x5)

Motor ASSY, Turn tabl (Spindle) (M901)

Chassis

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

3-4. “MOTOR ASSY (SLED) (M902)”, OPTICAL PICK-UP (DAX-25E)

1 Screw (B 1.7x5)

Cover, Gear

Screw ASSY, Feed

Chassis

Gear B

Motor ASSY (Sled) (M902)

4 Screw

(P 1.4x3.5)

Bracket (Shaft)

Optical pick-up (DAX-25E)

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

C412

C601

IC601

L602

L409

R408

R627

L601

D461

C604

C603

C602

R601

C630

C631

C629

C632

C633

C634

C635

R631

TP630

(RF)

R632

R633

R634

R635

R636

R637

R638

R639

R640

R624

C620

C615

C616

C617

C618

R618

R619

R620

R621

R622

R623

C619

IC402

C60

L302

R463

C461

C462

R461

R462

C607

C608

C626

C610

C621

C622

R625

R616

C613

C627

R615

L605

R432

C624

R317

R433

L606

Q409

120

RF level

0.45 to 0.65 Vp-p

VOLT/DIV : 100 mV (With the 10 : 1 probe in use) TIME/DIV : 500ns

SECTION 4

ELECTRICAL ADJUSTMENTS

The CD section adjustments are done automatically in this set.

Precautions for Check

1. Perform check in the order given.

2. Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise indicated.

3. Power supply voltage requirement :DC4.5 V in DC IN jack.

(J401) VOLUME button : Minimum HOLD switch : OFF

Focus bias Check

Condition:

• Hold the set in horizontal state.

Connection:

oscilloscope

(AC range)

TP630(RF)

[MAIN BOARD] (SIDE A)

Procedure:

1. Connect the oscilloscope to the test point TP630(RF) on the MAIN board.

2. Set a disc. (YEDS-18)

3. Press the >B button.

4. Check the oscilloscope waveform is as shown below. A good eye pattern means that the diamond shape (◊) in the center of the waveform can be clearly distinguished.

RF Signal reference Waveform (Eye Pattern)

To watch the eye pattern, set the oscilloscope to AC range and increase the vertical sensitivity of the oscilloscope for easy watch-ing.

5. Stop revolving of the disc motor by pressing the x button.

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

SECTION 5

DIAGRAMS

5-1. EXPLANATION OF IC TERMINALS

IC601 (SYSTEM CONTROL) CXD3029R (DSP IC)

Pin No. Pin name I/O Description

1 XRAM O DRAM low address strobe signal outut. 2 XWE O DRAM data input enable signal output.

3 to 6 D0 to 3 I/O DRAM data bus 0 to 3.

7 DCLK O Not used (OPEN). 8 DCKE O Not used (OPEN). 9 XCAS O DRAM column address storobe signal output.

10 WFCK O Not used (OPEN).

11 to 13 A7 to 9 O DRAM address 7 to 9.

14 DVss – Ground terminal for DRAM interface.

15 to 17 A4 to 6 O DRAM addres 4 to 6.

18 XRDE I/O Not used (OPEN). 19 VDD0 – Power supply for digital. 20 CLOCK I Serial data transfer clock input. 21 SDTO I Serial data input. 22 SENS O SENS output. 23 XLAT I Latch input. 24 XSOE I CPU serial data output enable signal input. 25 SYSM I Mute input. “H” : MUTE 26 WDCK O Word clock output. 27 SCOR O SCOR output. 28 XRST I Reset terminal. 29 PWMI I Spindle moter external contorol input. 30 XQOK I/O Not used (OPEN). 31 XWER I/O DRAM write enable signal input. 32 R4M O System clock output. 33 Vss0 – Digital ground terminal. 34 SQCK I Clock input for SQSO read out. 35 SCLK I Clock input for SENS serial date read out. 36 SQSO O Not used (OPEN). 37 XEMP O Not used (OPEN). 38 XWIH O Not used (OPEN). 39 SBSO O Not used (OPEN). 40 EXCK I Not used (Fixed at “L”). 41 XTSL I Not used (Fixed at “L”). 42 HVss – Ground terminal for headphones. 43 HPL O Headphone output (L-CH). 44 HPR O Headphone output (R-CH).. 45 HVDD – Power supply terminal for headphones. 46 XVDD – Power supply terminal for master clock. 47 XTAI I Master clock input. 48 XTAO O Master clock output. 49 XVss – Ground terminal for master clock. 50 AVDD1 – Power supply terminal for analog. 51 AOUT1 O Line out (L-CH). 52 VREFL O VREF terminal (L-CH). 53 AVss1 – Ground terminal for analog. 54 AVss2 – Ground terminal for analog.

D-EJ750/EJ751/EJ753/EJ755/EJ756CK/EJ758CK

Pin No. Pin name I/O Description

55 VREFR O VREF terminal(R-CH). 56 AOUT2 O Line out. 57 AVDD2 – Power supply terminal for analog. 58 TEST1 I Not used (Fixed at “L”). 59 TEST I Not used (Fixed at “L”).. 60 Vss1 – Not used (Fixed at “L”). 61 LRMU O OR output of L-CH/R-CH detection flag (AND output) and system flag. 62 DOUT O Not used (OPEN) 63 ATSK I/O Not used (OPEN). 64 DFCT I/O Not used (OPEN). 65 FOK I/O Focus OK signal I/O teminal. 66 MIRR I/O Not used (OPEN). 67 COUT I/O Not used (OPEN). 68 C2PO O Not used (OPEN). 69 GFS O Not used (OPEN). 70 XUGF O Not used (OPEN). 71 XPCK O Not used (OPEN). 72 VDD1 – Power supply terminal for digital. 73 PCO O Charge pump output for master PLL. 74 FILI I Filter input for master PLL. 75 FILO O Filter output for master PLL. 76 CLTV I VC01 contorol voltage input. 77 VCTL I VC02 contorol voltage input for wide range EFM PLL. 78 VPCO O Charge pump output for wide range EFM PLL. 79 AVDD 3 – Ground terminal for analog. 80 ASYO O EMF fullswing output. 81 ASYI I Asymmetric comparate voltage input. 82 BIAS I Asymmetric circuit current constrant input. 83 AVDD3 – Power supply terminal for analog. 84 RFAC I EFM signal input. 85 AVDD0 – Power supply terminal for analog. 86 IGEN I Current constant input for OP amplifier. 87 AVss0 – Ground terminal for analog. 88 RFDC I RF signal input. 89 CE I E signal input. 90 TE I F signal input. 91 SE I B signal input. 92 FE I A signal input. 93 VC I Center voltage input. 94 Vss2 – Digital ground terminal. 95 FRDR O Focus drive output. 96 FFDR O Focus drive output. 97 TRDR O Traking drive output. 98 TFDR O Traking drive output.

99 SRDR O Sled drive output. 100 SFDR O Sled drive output. 101 SSTP I Most inside disc detection signal input. 102 MDS O Spindle drive output. 103 MDP O Servo contorol output for spindle moter. 104 C176 O 176.44kHz output.

+ 19 hidden pages