– 1 –

Model Name Using Similar Mechanism CDX-4180

CD Drive Mechanism Type MG-363X-121

Optical Pick-up Name KSS-521A

SERVICE MANUAL US ModelCanadian Model

CDX-4250

E ModelCDX-4500

CDX-4250/4500

FM/AM COMPACT DISC PLAYER

MICROFILM

SPECIFICATIONS

Photo: CDX-4250

– 19 –

SECTION 4DIAGRAMS

4-1. IC PIN DESCRIPTION• IC801 µPD17705GC-534-3B9 (SYSTEM CONTROL)

Pin No. Pin Name I/O Pin Description

1 SIRCS I SIRCS input (A/D)

2 IN-SW I CD mechanism position detection

3 D-SW I CD mechanism position detection

4 SELF-SW I CD mechanism position detection

5 L-SW I LIMIT switch

6 LM-EJ O Loading motor control (Eject direction)

7 LM-LOD O Loading motor control (Loading direction)

8 AMP/ANT-ON O Power control for amplifier.

9 MONO O Force MONO output

10 SD I SD signal input

11 BAND-SW I Initialize switch input terminal

12 AREA1-SW I Initialize switch input terminal

13 AREA2-SW I Initialize switch input terminal

14, 15 RE1, 2 I Rotary encoder input 1, 2

16 SEEK O SEEK output

17 CD-ON I/O Servo drive power

18 FM-ON I/O FM select output

19 TU-ON I/O AM select output

20 NC — Not used.

21 GND3 — Ground

22 KEYIN3 I Not used (Connect to ground)

23, 24 KEYIN2, 1 I A/D key input 2, 1

25 ROT-IN I Rotary commander input

26 S-METER I FM and AM common signal meter A/D conversion input

27 TEST-SW I TEST mode select input

28 AM-IFC I AM center frequency input

29 FM-IFC I FM center frequency input

30 VDD2 — Power supply (+5 V)

31 VCOH-FM I Local oscillation frequency input (FM)

32 VCOL-AM I Local oscillation frequency input (AM)

33 GND2 — Ground

34 NC — Not used.

35 EO1-PDOUT O Error out output

36 TESTO — Connect to ground

37 AM-ON(TU-ON) O AM power output (AM select)

38 FM-ON(FM/AM) O FM power output (FM select)

39 LCL/DX O LOCAL/DX select (“H” : LOCAL, “L” : DX)

40 BEEP O BEEP output

41 ACC-IN I Accessory input

42 SCOR I SUBQ data read request

43 MUTE O System mute output

44 AMP-MUTE O Power amplifier mute output

45 TEL-MUTE O Telephone mute output

46 NC — Fixed at “H” in this set.

47 VOL-CE O Electric volume chip select

48 VOL-CLK O Electric volume serial clock

49 VOL-DATA O Electric volume serial data

50 EMPHO O De-emphasis control output

51 PW-ON O System power control

52 MD-ON O Loading motor power

53 CD-ON O Servo drive power

– 20 –

Pin No. Pin Name I/O Pin Description

54 ILL-ON O Illumination output

55 C.ALARM I Caution alarm select input (Used/Not used)

56 NC I Not used (Connect to ground)

57 NC — Fixed at “H” in this set.

58 LCD-CE O LCD drive chip select output

59 EZ-SEL I SHIFT + input

60 SENS I Information input from servo IC.

61 FOK I Focus OK input

62 LD-ON O Laser diode control

63 NC — Not used. (Connect to ground)

64 [IN] ST/MONO I/O Used for both STEREO indicator display input and force MONO output. (FM)

[OUT] MONO

65 LCD-CKO O LCD driver serial clock output

66 LCD-So O LCD driver serial data output

67 INH O INHbit output

68 SQ-CKo O Q data read serial clock output

69 CD-RST O Servo IC/DAC reset output

70 SQ-SI I Q data input

71 CD-SO O Serial data output to servo IC.

72 CD-LAT O Data latch output to servo IC.

73 CD-CKO O Serial clock output to servo IC.

74 VREF — Not used.

75 GND1 — Ground

76 X-OUT — Crystal oscillator connection (4.5 MHz)

77 X-IN I Crystal oscillator connection (4.5 MHz)

78 BU-IN I Back-up detection

79 VDD1 — Power supply (+5 V)

80 RESET I RESET input

4-4. SCHEMATIC DIAGRAM — CD MECHANISM SECTION — • Refer to page 22 for Waveforms and Note and page 37 for IC Block Diagrams.

CDX-4250/4500

– 25 – – 26 –

(Page 33)

4-5. PRINTED WIRING BOARD — DISPLAY SECTION —

Note:• ® : Through hole.• b : Pattern from the side which enables seeing.

(The other layer’s patterns are not indicated.)

Caution:Pattern face side: Parts on the pattern face side seen from the(Side B) pattern face are indicated.Parts face side: Parts on the parts face side seen from the(Side A) parts face are indicated.

• Semiconductor LocationRef. No. Location(D551) B-10(D552) B-10(D554) B-11D561 B-11D562 A-13D563 B-13D564 C-5D565 C-4

Ref. No. LocationD566 A-4D567 C-2D568 C-9D569 C-8D570 C-7D571 C-12D572 C-11D573 C-3

– 27 – – 28 –

CDX-4250/4500

D574 C-2D575 B-3D576 A-2D577 B-1D578 A-1

(IC551) B-7

Ref. No. Location

( ) : SIDE B

Note:• All capacitors are in µF unless otherwise noted. pF: µµF

50 WV or less are not indicated except for electrolyticsand tantalums.

• All resistors are in Ω and 1/4 W or less unless otherwise

specified.• U : B+ Line.• Power voltage is dc 14.4V and fed with regulated dc power

supply from ACC and BATT cords.

• C : panel designation.• Voltage is dc with respect to ground under no-signal

(detuned) condition.no mark : FM

• Voltages are taken with a VOM (Input impedance 10 MΩ).Voltage variations may be noted due to normal productiontolerances.

4-6. SCHEMATIC DIAGRAM — DISPLAY SECTION —

– 29 – – 30 –

CDX-4250/4500

(Page 36)

Note:• All capacitors are in µF unless otherwise noted. pF: µµF

50 WV or less are not indicated except for electrolyticsand tantalums.

• All resistors are in Ω and 1/4 W or less unless otherwise

specified.• ¢ : internal component.• C : panel designation.• U : B+ Line.• Power voltage is dc 14.4V and fed with regulated dc power

supply from ACC and BATT cords.• Voltage is dc with respect to ground under no-signal

(detuned) condition.no mark : FM( ) : AM< > : CD PLAY

∗ : Impossible to measure• Voltages are taken with a VOM (Input impedance 10 MΩ).

Voltage variations may be noted due to normal productiontolerances.

• Signal path.F : FMf : AMJ : CD

• AbbreviationCND : Canadian model.

4-8. SCHEMATIC DIAGRAM — MAIN SECTION (1/2) —

– 33 – – 34 –

CDX-4250/4500

(Page 26)

– 35 – – 36 –

4-8. SCHEMATIC DIAGRAM — MAIN SECTION (2/2) — • Refer to page 39 for IC Block Diagrams.

(Page 29)

CDX-4250

CDX-4250/4500

– 37 –

• IC Block Diagrams

IC1 CXD2507AQ

IC3 BA6796FP-T1

XLON

SPOD

SPOC

SPOB

SPOA

CLKO

VDD

CNIN

SEIN

CLOK

XLAT

XLTO

DATO

52535455565758596061626364

51SERVO AUTOSEQUENCER

33

3435363738

39

40414243

454647484950

44

DATAXRSTSENSMUTESQCKSQSOEXCKSBSOSCORVSSWFCKEMPH

DOUT

C4MFSTTXTSLXTAOXTAI

MNTO

20 21 22 23 24 25 26 27 29 30 31 3228

LRCK

PCM

DBC

LKGT

OPXU

GFXP

CKVD

DGF

SRF

CKC2

POXR

OFM

NT3

MNT

1

1

23456

789

101112

161718

19

13

1415

FOK

MONMDPMDS

LOCKTEST

FILOFILIPCOVSS

AVSSCLTVAVDD

RFBIASASYI

ASYOASYE

WDCK

5

14CPU

INTERFACESUB CODE

PROCESSOR

DIGITALCLV

EFMDEMODULATOR

DIGITALPLL

ASYMMETRYCORRECTOR

5 D/AINTERFACE

ERRORCORRECTOR

3

6

3

16KRAM

DIGITALOUT

CLOC

KGE

NERA

TOR

4

1 2 3 4 5 6 7 8 9 10 11 12 13 14

OPOU

T

CH4-

IN

CH4

CTL1

CTL2

FWD

REV

TRAY

GND

CH3

–

CH5

–

COM

CH4

+

CH3

+

CH3-

IN

CH3

VREF

CH2

CH2-

IN

VCC

VCC

CH1

–

CH2

–

CH1-

IN

OP IN

–

CH1

CH1

+

OP IN

+

CH2

+

DRIVEBUFFER

DRIVEBUFFER

DRIVEBUFFER

DRIVEBUFFER

DRIVEBUFFER

DRIVEBUFFER

DRIVEBUFFER

DRIVEBUFFER

DRIVEBUFFER

LEVELSHIFT

LEVELSHIFT

LEVELSHIFT

LEVELSHIFT

THERMALSHUTDOWN

1516171819202122232425262728

LOGIC

CTL1 CTL2 FWD REV

V/I

– 38 –

IC2 CXA1782BQ

36 35 34 33 32 31 30 29 28 27 26 25

24

23

22

21

20

19

18

17

16

15

14

13

121110987654321

37

38

39

40

41

42

43

44

45

46

47

48

PHD

2

PHD

1

PHD

LD RF O

RF I

CP CB CC1

CC2

FOK

SENS

C.OUT

XRST

DATA

XLT

CLK

VCC

ISET

SL O

SL M

SL P

TA O

TA M

FSET

TG2

TGU

SRCH

FE OFLB

FGD

FDFC

T

FE MFE

I

FEO

FE BIAS

F

E

EI

VEE

TED

LPFI

TEI

ATSC

TZC

TDFCT

VC

APC LEVEL SFO

K

MIRR

RF IV AMP1

RF IV AMP2

FE A

MP

TTL

IIL

FZC COMP

DFCT

IIL

TTL

IIL DATA REGISTER INPUT SHIFT REGISTER

ADDRESS DECODER

OUTPUT DECODER

TTL

IIL

TOG1-3BAL1-3

FS1-4 TG1-2 TM1-7 PS1-4F IV AMP

E IV AMP

BAL1

BAL2

BAL

3

TE AMP

TZC COMP

DFCT

TM1

DFCT

FS4

ATSC

WINDOW COMP

TOG1

TOG2

TOG3

FCS PHASECOMPENSATION

FS1

F SE

TTG2

TM7

TM3

TM4

TM5

TM6

ISETTRACKINGPHASECOMPENSATION

HPF COMP LPF COMP

TG1

FS2

TM2

RF M

– 39 –

IC402 TDA7384

IC401 LC75374E

+–

+–

+–

+–

+–

+–

+–

+–

+–

+–

+–

+–

+–

+–

DECODER LATCH SHIFTREGISTER

CONTROL

–+

+–

1 2 3 4 5 6 7 8 9 10

20

19

18171615

14

13

12

11

21

22

2324252627282930313233

3435363738

39

4041424344

LSELOL4L3L2L1

VDD

R1R2R3R4

RSELO

RVRI

N

RCOM RT

1RT

2

RT3

RTOU

TRS

IN NC NCRS

B1

RSB2

RFIN

RFOUT

RROUTVSS

CLDICE

VREF

LROUT

LFOUT

LFIN

LSB2

LSB1

NCNCLSIN

LTOU

T

LT3

LT2

LT1

LCOM

LVRI

N

DRIVER DRIVER DRIVERDRIVER

1 2 3 4 5 6 1310 12117 8 9 16 191817 20 2524232221

TAB

GND

OUT2

–ST

NBY

OUT2

+

VCC

OUT1

–GN

DOU

T1+

SVR

IN1

IN2

S-GN

DIN

4IN

3AC

-GND

OUT3

+GN

DOU

T3–

VCC

OUT4

+M

UTE

OUT4

–GN

DN.

C.

14 15