kenwood KDC-V7521, KDC-V7521Y Service Manual

CD RECEIVER

Escutcheon assy (B07-3007-03)

Front glass (B10-4161-01)

Panel assy (A64-2582-02)

KDC-V7521/Y

This service manual does not include information on the CD mechanism assembly (exploded view, parts list, schematic diagram or mechanism operation description).

For such information, please refer to the CD mechanism assembly service manual (X92-4030-0X, X92-4440-0X, : B51-7867-00).

DC cord (E30-4942-05): KDC-V7521Y (E30-4956-05): KDC-V7521

Antenna adaptor (T90-0523/0534-05)

Screw set (N99-1704-05)

Lever (D10-4562-04) (D10-4621-04):KDC-V7521

Mounting hardware assy (J21-9716-03)

Torsion coil spring (G01-2924-04)

Plastic cabinet assy (A02-1497-13)

Remote controller assy (A70-2025-05)

Remote controller assy (A70-0886-15)

KDC-V7521/Y

SERVICE MANUAL

KDC-V7521/Y

A1,Q53

AUDIO OUT

F/E

S-METER

IFC OUT

PLL DATA

PLL CLK

SCL

SDA

SW1 SW2

SW3 MUTE L MUTE R

RST

STOP LO/EJ

MO SW

RST

REQ C

CLK

DATA H

CH-CON

REQ H

DATA C

SW5V

Q43,44 Q45,46

1200mV

SERVO+B A8V BU5V

BACK UP

KEY MATRIX

PLL+B FM+B AM+B

1200mV

IC2

REMO

IC14 Q52

DECODER

IC1

BU5V

REMO

RESET

MUTE

DRIVER

IC16

RESET IC

RESET

IC1

LCD DRIVER

ED1

LCD (BACK LIGHT V-ILL)

RDS

RDCK

SW5V

QUAL

RDDA

L CE

L CLK

L DATAL

L DATAS

(X16- )

PANEL 5V

LCD AVR

SW5V

Q36

NOISE

BUFFER

NOISE

SYSTEM MI-COM

Q3,4

G/R SW V-I

251mV 230mV

SCL

SDA

DA SDA

DA SCL

IC3

DAC

CONVERTER

V-ILL

IC2

FM AM CD CH

QUAL

ILL+B

A8V

E-VOL

AFS

SRM SW1

SRM DET

SRM SW2

SRM MECHA.

ILLUM

MUTE

P MUTE

SW5V

PANEL5V

SRM SW3

SRM SUB-

SRM SUB+

Q10-13

Q30

BU DET.

SRM MOTOR DRIVER

IC15

Q15

DIMMER

Q31

ACC DET.

Q50,51

SERVO+B

PANEL 5V

A8V

Q37-40

MUTE

DRIVER

SERVO AVR

IC3 Q4-6

Q7,8

IC8 Q32,33,35

SW5V

A8V

SW14V

IC4 POWER IC

BU5V

Q1,2

BU5V

Q26-29

P CON

Q14

EX.AMP CONTROL

2WAY

MUTE

PRE OUT OUTPUT VOLTAGE

CD 3600mV

1372mV

FM AM

CHANGER

855mV

3600mV

SP-OUT

EX.AMP CONTROL

DIMMER

TEL-MUTE NAVI-MUTE

ACC

P-CONT A-CONT

BACK UP

BLOCK DIAGRAM

KDC-V7521/Y

COMPONENT DESCRIPTION

●SWITCH UNIT (X16-154X-XX, X16-1892-70)

Ref.No.

IC1 LC75808W LCD driver with key matrix IC2 RS-171 Remote sensor IC IC3 M62333FP D/A converter Q1 DTA114EUA or KRA302 Key permission SW Q3 2SC4081 Red LED SW When a base goes Hi, RED LEDs are turned on. Q4 2SC4081 Green LED SW Q5 2SC4081 VLCD AVR For LCD driver IC

Q6 DTA114EUA or KRA302 REMO SW

Q50-55 UMX2N Constant current driver

Q62 2SC4081 Buffer

Q63 2SC4081 Buffer

Q64 2SC4081 Buffer

Component name Application/Function Operation/Condition/Compatibility

The brightness control of red, green and blue colour For the key scanning start and the key detection SW

When a base goes Hi, GREEN LEDs are turned on.

While a base goes Lo, PAN 5V is supplied to the Remote sensor IC. The current control of red, green and blue LEDs for the variable illumination The control voltage of the constant current driver for red colour The control voltage of the constant current driver for green colour The control voltage of the constant current driver for blue colour

●ELECTRIC UNIT (X25-9392-7X, X25-8762-72)

Ref.No.

IC1 UPD703033GC139 System MI-COM. IC2 TDA7407D E. VOL & N.C. MPX IC

IC3 M5237ML AVR IC

IC4 TA8273H Power IC

IC8 or TC74HC02AF Mute logic 2-input NOR x 4

IC14 TDA7479D RDS decoder IC15 LB1930M Motor driver IC For SRM mechanism drive IC16 S-80837ANNP Reset IC Q1 2SB1548 (P) Q2 2SC4081 or 2SD1819A Q1 and Q2 are inverted Darlington connection.

Q3 2SA1576A or 2SB1218A SW 5V

Q4 2SB1548 (P) A8V AVR Q4 is combined with IC3, and it outputs +8.3V. Q5 DTC144EUA or UN5213

Q6 DTA124EUA or KRA303

Q7 DTA124EUA or KRA303

Q8 DTC144EUA or UN5213

Component name Application/Function Operation/Condition/Compatibility

IC is combined with Q4, and it works as the error detection, the driver.

HD74HC02FP

or 74VHC02SJ

When BU 5V voltage is less than 3.7V, IC outputs Lo.

BU 5V AVR

A8V AVR SW While Q5's base goes Hi, Q6 is turned on, and

SW14V SW While Q8's base goes Hi, Q7 is turned on, A8V

While BACKUP is applied, AVR outputs +5V.

While a base goes Lo, SW 5V is supplied to the microprocessor peripheral circuits.

A8V AVR ON/OFF control

A8V AVR is working. A8V AVR and SERVO +B AVR ON/OFF control

AVR and SERVO +B AVR are working.

KDC-V7521/Y

COMPONENT DESCRIPTION

Ref.No.

Q9 2SD2375 SERVO +B AVR

Q10 2SB1184

Q11 2SC4081 or 2SD1819A

Q12 DTC144EUA or UN5213

Q13 DTA124EUA or KRA303

Q14 DTA123JK or KRA105S EXT. AMP CON. SW

Q15 DTC144EUA or UN5213 Small lamp detection SW

Q26 2SB1277 (Q, R) Q29 DTC114YUA or UN5214 Works during POWER ON mode.

Q27 2SA1576A or 2SB1218A P-CON. protection SW

Q28 DTA124EUA or KRA303 P-CON. protection inhibit SW

Q30 2SC4081 or 2SD1819A BU detection SW

Q31 2SC4081 or 2SD1819A ACC detection SW

Q32 DTA124EUA or KRA303 Mute driver for L Ch.

Q33 DTA124EUA or KRA303 Mute driver for R Ch.

Q35 DTC124EUA or UN5212 E. VOL mute SW

Q36 2SC4081 or 2SD1819A Noise buffer Q37 DTC143TUA or KRC410 Audio mute SW (Front L) When Q37's base goes Hi, Pre-output is muted. Q38 DTC143TUA or KRC410 Audio mute SW (Front R) When Q38's base goes Hi, Pre-output is muted. Q39 DTC143TUA or KRC410 Audio mute SW (Rear L) When Q39's base goes Hi, Pre-output is muted. Q40 DTC143TUA or KRC410 Audio mute SW (Rear R) When Q40's base goes Hi, Pre-output is muted.

Q43 DTC124EUA or UN5212

Q44 2SB1277 (Q, R)

Q45 DTC124EUA or UN5212

Q46 2SB1277 (Q, R) Q50 DTC144EUA or UN5213

Q51 2SA1576A or 2SB1218A Q52 2SC4081 or 2SD1819A Composite signal output buffer Q53 DTC144EUA or UN5213 IFC buffer Waveform shaping

Component name Application/Function Operation/Condition/Compatibility

When Q9's base goes Hi, SERVO +B AVR outputs +7.6V. While Q11's base goes Hi, AVR outputs +10.7V.

ILL +B AVR Works during POWER ON mode with a panel

attached to the set. ILL +B AVR ON/OFF control

ILL +B SW While Q12's base goes Hi, Q13 is turned on, and

ILL +B AVR is working. When a base goes Lo, Q14 is turned on, and control pulse waveform shape is outputted. When vehicle small lamps turn on, Q15 is turned on .

P-CON SW

FM +B SW A8V is supplied to the F/E.

AM +B SW A8V is supplied to the F/E.

PAN 5V SW

When Q29's base goes Hi, Q26 is turned on .

Protect Q26 by turning ON when P-CON output is grounded. Prevents Q27 tuning ON during start-up after power ON. While BACKUP is applied, a base goes Hi, and Q30 is turned on. When momentary power down has detected, a base goes Lo, and Q30 is turned off. While ACC is applied, a base goes Hi, and Q31 is turned on. When BU detection SW or System RESET or MICOM.'s Pre-mute is working, a base goes Lo, and Q32 and Q33 are turned on. When BU detection SW or MI-COM.'s mute is working, a base goes Hi, and Q35 is turned on.

When Q43's base goes Hi, Q44 is turned on, and

Works during FM reception mode. When Q45's base goes Hi, Q46 is turned on, and

Works during AM reception mode. While a panel is attached to the set, Q50 and Q51 are turned on, and BU 5V is supplied to the panel.

KDC-V7521/Y

MICROCOMPUTER’S TERMINAL DESCRIPTION

● IC1 (ELECTRIC UNIT : X25-9392-7X, X25-8762-72)

Pin No.

1 AM+B O AM+B control Hi : During AM reception

2 FM+B O FM+B control

3 AFS O Noise detection time constant switching terminal

4 PLL-DATA I/O Data input/output with F/E 5 PLL-CLK I/O Clock output to F/E 6 EVDD - Positive power supply connection terminal Connected to BU 5V lines. 7 EVSS - Ground connection terminal Connected to GND lines. 8 N.C. O Not used (N.C.) 9 BEEP O BEEP sound output 10 REMO I Data input from the remote control light sensor

11 PRE-MUTE L O Pre-out mute control (L)

12 PRE-MUTE R O Pre-out mute control (R)

13 IC2-SDA I/O Data line with IC2,CD mechanism MI-COM. 14 IC2-CLK O Clock line with IC2,CD mechanism MI-COM. 15,16 N.C. O Not used (N.C.)

17 DA-SDA / DIM-CON O

18 TEST - Test terminal Not used (Connected to GND lines)

19 P-MUTE O Power IC mute control output

20 P-STBY O Power IC standby control output

21 MUTE O IC2 mute control output OPEN (Hi) : Mute ON, Lo : Mute OFF 22,23 N.C. O Not used (N.C.) 24 ACC-DET I ACC detection terminal Lo : ACC ON, Hi : ACC OFF 25 DIMMER I Small lights detection input Lo : During vehicle small lamps turn on. 26 SW5V O SW 5V control output Lo : POWER ON mode

27 EXT-AMP-CONT O External amp. control output Bass boost LOW__Hi : 130msec, Lo : 70msec

28 P-CON O Power control output Lo : POWER OFF mode, Hi : POWER ON mode 29 ANT-CON O Antenna control output Hi : During TUNER mode or TI reception 30 P-ON O SW 14V control output Hi : POWER ON mode 31 RESET I Reset input terminal Lo : System reset 32 XT1 I Sub clock resonator connection terminal Clock count during POWER OFF mode

Pin Name I/O Description Processing Operation

Hi : During FM reception, Hi : During FM reception if with RDS, RDBS Hi : During FM reception, Lo : During FM seek or AF search

When M MUTE L input is Lo during CD source selected, PRE MUTE L outputs Lo. When M MUTE R input is Lo during CD source selected, PRE MUTE R outputs Lo.

Data output to D/A converter (V-LED model) Data line with D/A converter / Dimmer control output

/ Hi : Dimmer OFF, Pulse wave shape : Dimmer ON

Lo : Mute (during POWER OFF, ALL OFF, TEL MUTE) Lo : Power IC OFF, Hi : Power IC ON, ALL OFF mode

Bass boost OFF__Hi : 160msec, Lo : 40msec

Bass boost HI__ Hi : 100msec, Lo : 100msec

KDC-V7521/Y

MICROCOMPUTER’S TERMINAL DESCRIPTION

Pin No.

33 XT2 - Sub clock resonator connection terminal

34 REGC -

35 X2 - Main clock resonator connection terminal POWER OFF mode or momentary power down

36 X1 I Main clock resonator connection terminal 37 VSS - Ground connection terminal Connected to GND lines. 38 VDD - Positive power supply connection terminal Connected to BU 5V lines. 39 CLKOUT O Internal system clock output Not used (N.C.) 40,41 N.C. O Not used (N.C.) 42 TYPE0 I Destination type selection terminal 0 43 TYPE1 I Destination type selection terminal 1 44 TYPE2 I Destination type selection terminal 2 45 N.C. O Not used (N.C.) 46 IC2 TYPE0 I IC2 setting terminal Lo : Initial value 47 IC2 TYPE1 I IC2 setting terminal Lo : Initial value 48 CH-REQH O Request output to changers Lo : Request 49 CH-RST O Reset output to changers : Reset 50 CH-MUTE I Mute request from changers Hi : Mute request 51 CH-CON O Changer control Lo : Standby mode, Hi : Operation mode 52 ILL-ON O Illumination AVR on/off control output Hi : POWER ON mode except panel detached 53 M-MUTE L I Mute request (L Ch.) from CD MECHA. MI-COM. Lo : Mute request 54 M-MUTE R I Mute request (R Ch.) from CD MECHA. MI-COM. Lo : Mute request 55 BVDD - Positive power supply connection terminal Connected to BU 5V lines. 56 BVSS - Ground connection terminal Connected to GND lines. 57 M-RST O Reset output to CD mechanism MI-COM. Lo : Reset 58 M-STOP O Stop request to CD mechanism MI-COM. Lo : Stop mode, Hi : Operation mode 59 N.C. O Not used (N.C.) 60 LO/EJ I/O CD mechanism loading/Eject switching output Lo : Loading, Hi : Eject, Hi-Z : Stop or Break 61 MOSW O CD mechanism loading motor control output Hi : CD loading/eject action or Break, Lo : other 62 N.C. O Not used (N.C.) 63 CD-SW3 I Down & limit switch detection input Hi : Chucking, Lo : Pickup most inner position

64 DA-SDA/NC O Clock output to D/A converter (V-LED model)

65 LCE O CE output to LCD driver IC 66-69 N.C. O Not used (N.C.) 70 AV CONT O A/D converter reference voltage control output Hi : Active, Connected to AVREF terminal

71 AVDD -

Pin Name I/O Description Processing Operation

Capacitor conection terminal for regulator inside microprocessor

Oscillation : POWER ON mode, Oscillation stop :

detected

Lo : Panel detached, momentary power down detected

A/D converter positive power supply connection terminal

Connected to BU 5V lines.

KDC-V7521/Y

MICROCOMPUTER’S TERMINAL DESCRIPTION

Pin No.

72 AVSS - A/D converter ground connection terminal Connected to GND lines. 73 AVREF I A/D converter reference voltage input terminal

74 PHONE I PHONE detection input

75 SRM-SW3 I Mask mechanism position SW3 input

76 SRM-SW1 I Mask mechanism position SW1 input

77 SRM-SW2 I Mask mechanism position SW2 input

78 SRM-DET I Mask mechanism detection input

79 NOISE I FM noise detection input 80 S-METER I S-meter input from F/E

81 R-DATA I Data input from the RDS decoder IC

82 R-QUAL I Quality input from the RDS decoder IC

83 IFC-OUT I F/E IFC OUT input terminal Lo : Station detected, Hi : Not detected 84,85 N.C. I Not used(pull down to GND lines)

86 SRM-B O SRM mechanism submotor control output

87 R-CLK I Clock input from the RDS decoder IC

88 CH-REQC I Request input from changers Lo : Request 89 KEY-REQ I Communication request from LCD driver IC 90 CD-SW1 I Loading SW detection input Lo : Loading start 91 CD-SW2 I 12cm disc detection SW input Lo : 12cm disc detected 92 SRM+B O SRM mechanism submotor control output

93 BU-DET I Momentary power down detection input

94 CH-DATAC I Data input from changers 95 CH-DATAH O Data output to changers 96 CH-CLK I/O Clock input/output with changers 97 L-DATA L I Data input from the LCD driver IC 98 L-DATA S O Data output to the LCD driver IC

99 L-CLK I/O

100 PAN5V O Panel 5V control Hi : Panel attached, Lo : Panel detached

Pin Name I/O Description Processing Operation

1V or less : TEL MUTE, 2.5V or greater : NAVI MUTE Panel : (SW1,SW2,SW3)=(Lo,Lo,Hi) Angle : (SW1,SW2,SW3)=(Hi,Hi,Lo) Eject : (SW1,SW2,SW3)=(Hi,Hi,Hi) Mask : (SW1,SW2,SW3)=(Lo,Lo,Lo) Lo : Mechanism detected, Hi : mechanism not detected

Except RDS, RBDS model : Not used (pull down to GND lines) Except RDS, RBDS model : Not used (pull down to GND lines)

Standby : (SRM+B,SRM-B)=(Lo,Lo) Clock wise : (SRM+B,SRM-B)=(Hi,Lo) Counter clock wise : (SRM+B,SRM-B)=(Lo,Hi) Break : (SRM+B,SRM-B)=(Hi,Hi) Except RDS, RBDS model : Not used (pull down to GND lines)

Hi : When momentary power down detected or BU OFF Lo : BU ON

Clock output to the LCD driver IC /Panel detaching detection input(LCD Driver)

Lo : Panel attached

+ 16 hidden pages