Sony CDX-CA600 Bedienungsanleitung

Ver 1.0 2001. 12

Model Name Using Similar Mechanism CDX-L300/L460X

CD Drive Mechanism Type MG-393XA-121//K

Optical Pick-up Name KSS-720A

SERVICE MANUAL

AEP Model

UK Model

CDX-CA600/CA600X

E Model

CDX-CA600X

CDX-CA600/CA600X

FM/MW/LW COMPACT DISC PLAYER

CD player section

Signal-to-noise ratio 90 dB

Frequency response 10 – 20,000 Hz

Wow and flutter Below measurable limit

Tuner section

Tuning range 87.5 – 108.0 MHz

Aerial terminal External aerial connector

Intermediate frequency 10.7 MHz/450 kHz

Usable sensitivity 8 dBf

Selectivity 75 dB at 400 kHz

Signal-to-noise ratio 66 dB (stereo),

72 dB (mono)

Harmonic distortion at 1 kHz

0.6% (stereo),

0.3% (mono)

Separation 35 dB at 1 kHz

Frequency response 30 – 15,000 Hz

MW/LW

Tuning range MW : 531 – 1,602 kHz

LW : 153 – 279 kHz

Aerial terminal External aerial connector

Intermediate frequency 10.7 MHz/450 kHz

Sensitivity MW : 30 µV

LW : 40 µV

SPECIFICATIONS

Power amplifier section

Outputs Speaker outputs

(sure seal connectors)

Speaker impedance 4 – 8 ohms

Maximum power output 50 W ×4 (at 4 ohms)

General

Outputs Power aerial relay control lead

Input Telephone ATT control lead

Tone controls Bass ±9 dB at 100 Hz

Treble ±9 dB at 10 kHz

Power requirements 12 V DC car battery

(negative earth)

Dimensions Approx. 178 ×50 ×177 mm

(w/h/d)

Mounting dimensions Approx. 182 ×53 ×161 mm

(w/h/d)

Mass Approx. 1.2 kg

Supplied accessories Parts for installation and connections (1 set)

Front panel case (1)

Card remote commander RM-X115 (E model)

Note

This unit cannot be connected to a digital preamplifier or an equalizer.

Design and specifications are subject to change without

notice.

Photo: CDX-CA600X

• The tuner and CD sections have no adjustments.

Sony Corporation

e Vehicle Company

Published by Sony Engineering Corporation

9-873-434-01

2001L0400-1

15 15

CDX-CA600/CA600X

D/A

CONV

TRACKING

ERROR

FORCUS

ERROR

OSC

EFM

DEMOD

SERVO

CTL

DSUB CODE

PROCESS

I/F

DRIVE

FOCUS

COIL

DRIVE

TRACKING

COIL

DRIVE

SLED

MOTOR

DRIVE

SPINDLE

MOTOR

DRIVE

MOTOR

DRIVE

62 63 64 65

CDMD ON

SWITCH

Q913,914

CD ON

SWITCH

Q915

CD+5V

REG

Q916,D927

CD DRIVE+6V

REG

Q912,D926

M902

(SLED)

M901

(SPINDLE)

M903

(LOADING)

SW3

(DISC IN)

SW2

(SELF)

SW4

(LIMIT)

SW1

(DOWN)

16.9344MHz

OPTICAL PICK-UP

KSS-720A

I-V

CONV.

CDL

STB

CD_TSO

31 CD_PACK

51 TSTB

CD TSI

CD TCKO

CD_RST

RFOK

XEN

D SW

INSW/PH2

CD_SELFSW

LIMIT

CD_LM _LO

CD_LM_ EJ

CDMD ON

XCD ON

R-CH

TUNER

SECTION

23 24

2RESET

S801

(RESET)

IC802

BU+5V

BATT

D925

LOUT

ROUT

PACK

TSTB

TSI

TSCK

RFOK

SCK

STB

XTALEN

RST

RESET

A+5V

APC

FCS-

FCS+

TRK+

TRK-

SL-

SL+

SP+

SP-

LD-

LD+

FOCUS

COIL

TRACKING

COIL

LOAD

EJECT

SYSTEM CONTROL

IC801(1/3)

RF AMP,DIGITAL SERVO

DIGITAL SIGNAL PROCESSOR

IC1

FOCUS/TRACKING COIL DRIVE,

SLED/SPINDLE/LOADING MOTOR DRIVE

IC2

• Signal path

:CD

• R-ch is omitted due to

same as L-ch.

A+5V

AU+5V

D+5V

DR+6V

3-2. BLOCK DIAGRAM — CD SECTION —

(Page 16)

1616

CDX-CA600/CA600X

PJ601

(ANTENNA) 2 10

ANTFM MPX

CDL

AM DET

S-METER

I2C SDA

I2C SCL

E2PROM SDA

E2PROM SCL

RDS DET

ANTAM

TUNER UNIT

TU601

SYSTEM CONTROL

IC801 (2/3)

ELECTRONIC VOLUME

IC402

AUX L

OUT LF

OUT LR

OUT RF

OUT RR

BEEP

ATT

AMP ON

AMP ATT

TEL ATT

ACC IN

CD L

MPX

R-CH

LEVEL

MPIN

SDA

SCL

MUTE

17 QUAL

VOL ATT

7QUALITY

90 MS MASK

VSM

I2C SIO

I2C CKO

FUNCSEL

EE SIO

EE CKO

MPTH

DAVN

AUDIO OUT REAR

SECTION

LINE MUTE

SWITCH

Q904,905

Q402

MUTE

R-CH

Q401

MUTE

22 MUTE

4STBY

16 AUX

12 5

POWER AMP

IC401

-1

-2

-5

-6

-3

-4

CNP901

R-CH

PJ401

FL+

FL-

RL+

RL-

FR+

FR-

RR+

RR-

16 +B (BATT)

13 ATT

5AMP R

ANT R

GND

R-CH

BATT

F901

10A

TEL

ATT

Q901

TUNER +5V

REG

Q911,D918,919

NOISE

SUPPRESSOR

D601

BUFFER

Q601

TUNER ON

SWITCH

Q909,910

+8V REG

Q906,D917

POWER ON

CONTROL

Q907,908

AMP B+

CONTROL

SWITCH

Q921

AMP B+

SWITCH

Q920

AMP B+

CONTROL

SWITCH

Q917

AMP B+

SWITCH

Q922

7ACC

15 TEST

TUN ON

TEST IN

ACC

DETECT

Q902, D914

PW ON

SYSRST

BUSON

BUSSI

BUSCKO

BUSSO

BU IN

BATT

BATT DET

Q801,D801,802 BATT

+5V REG

Q93,D916 BATT+5V

+8V

TUNER

+8V

TUNER

+5V

BATT

AUDIO OUT FRONT

R-CH

BUS AUDIO IN

R-CH

•Signal path

:FM

:MW/LW

:CD

•R-ch is omitted due to same as L-ch.

CDRR-CH 2CD R

16 MPX

4OSCD

5OSCI

LVIN

SDA

SCL

MPTH 2

DAVN 8

RDS DECODER

IC601

BUS INTERFACE

IC803

13 RST

12 BUSON

8DATA OUT

11 CLK IN

9DATA IN

10 B/U-C

DATA I/O

CLK

RST

BATT

CNJ801

BUS

CONTROL IN

CA600X

CA600

BU+5V

NOISE AMP

IC602

MS MASK

SWITCH

Q602

X601

4.332MHz

DELAY BATT

D921,922

BUSON

3-3. BLOCK DIAGRAM — TUNER SECTION —

(Page 15)

17 17

CDX-CA600/CA600X

KEY MATRIX

S501-521

KEY

ACTIVE

Q803

REMOTE

RECEIVE

CNP801

(REMOTE IN) IC552

X802

32.768kHz

518

194

SYSTEM CONTROL

IC801 (3/3)

LCD DRIVE

IC501

KEY IN0 DATA

CLK

LCD SO

LCD CKO

LCD CE

ILL ON

SWITCH

Q919

ILL B+

REG

Q918

KEY IN1

KEY ACK

AD ON

RC IN1

RC IN0

SIRCS

XIN

XOUT

OSC OUT

ILL ON

BATT

ILL+5V

OSC IN

X801

18.432MHz LED549,550

LCD BACK

LIGHT

COM1

COM4

LCD

LCD501

ILL+5V

D531-559

D809

D807

()

KEY

ILLUMINATION

()

D561-589

KEY

ILLUMINATION

()

•

S25

•

S27

S38

•

S40

S47

DATA

CLK

LED

DRIVE

Q502

P1/S1

BATT

INH

LED DRIVE

SWITCH

Q503

LED

DRIVE

Q501

CA600

CA600X

3-4. BLOCK DIAGRAM — DISPLAY SECTION —

MAIN board

tuner unit

(TU601)

DISPLAY board

SERVO board

IN SELF SW board SPEAKER board

SL SW board

3-5. CIRCUIT BOARDS LOCATION

• Waveforms

— Servo Board —

(MODE: CD PLAY)

IC1 ts (PACK)

IC1 uj (RFO)

1.2Vp-p

Approx. 100mVp-p

IC1 oa (FEO)

Approx. 100mVp-p

IC1 od (TEO)

2Vp-p

16.9344MHz

IC1 wd (XTAL)

5Vp-p

3.2msec

— Main Board —

32.768kHz

IC801 qh (XOUT)

18.432MHz

IC801 qs (OSCOUT)

2.2Vp-p

5Vp-p

4.332MHz

IC601 4(OSCD)

5.2Vp-p

2020

CDX-CA600/CA600X

IC B/D

TP77

TP78

R29

R30

C43

TP79

TP80

TP81

TP82

TP83

TP84

CN2

CN3

TP85

M902

M901

SW2 TP4

TP2

TP3

M903

TP87

TP86

TP9 TP8

R3 R26

TP10

C13

C11

C10

TP7

TP92

TP17

TP20

TP16

TP19

R25

TP21

TP18

R24

TP6

C17

FB1

TP11

TP12 C9

C14

TP89

C19

C20 C23

TP22

TP23

TP24

TP25

TP88

FB4

C26

TP32

R14

R15

TP30

R12

R10

TP91 C37

TP90

TP29

TP28

TP26

TP27

R21

R22

TP34

TP35

TP36

TP46

TP37

TP38

TP39

TP40

TP41

TP42

TP43

TP44

TP45

FB2

CN1

R18

R19

R20

R17

TP66

FB7

FB6

TP62

TP47

TP63

TP48

TP49

TP64

TP50

TP51

TP52

TP68

TP53

TP69

TP54

TP70

TP55

TP71

TP56

TP72

TP57

TP73

TP58

TP74

TP59

TP75

TP60

TP76

TP61

SW3

SW4

CN13

C18

IC2

FB3

IC1

SW1

TP1

TP5

C44

C40

C1 C5

C3 C6

C15

C16

C41

C27

C45

C34

C29

C25

C36

C38

C35

C24

C30

C22

C21

•Refer to page 17 for Waveforms.

3-7. SCHEMATIC DIAGRAM —CD MECHANISM SECTION —•Refer to page 26 for IC Block Diagrams.

(Page 23)

Note:

• Voltage is dc with respect to

ground under no-signal conditions.

no mark : CD PLAY

21 21

CDX-CA600/CA600X

234567891011121314

R822

R603

C405

R417

R869

Q907

R602

C812

R601

R908

R840

C417

R413

R416

C707

C708

D805

C906

D922

D925

IC801

R930

Q917

Q901

Q801

D921

D820

R805

R807

R404

Q909

D804

D906

C801

IC602

R612

Q914

Q916

C918

IC601

Q911

Q403 Q401

Q402

Q904

R828

C611

R605

IC402

R412

FB801

R819

C420

C802

R701

R816

R814

R813

R868

R835

R607

R925

C703

C622

C632

R827

C623

C626 C618

C615

R620

R615

R842

C627

R621

C634

C631

C633

Q602

C604

JR703

R810

C602

C418

C613

R817

Q910

C702

R410

Q920

C607

R823

R851

R619

C601

R839

C409

C421

C621

R609

Q918

C803

C814

R867

C610

R614

R821

R934

R617

R911

C809

R409

Q908

C810

C808

R850

R604

R402

R923

R613

C628

D602

R616

R852

R401

C624

C616

C625

R608

C619

R901

R418

R812

Q601

C815

C407

R704

R419

R415

R907

JR901

C408

R833

R853

R826

C406

R806

R854

Q404

D806

C617

R906

R915

R865

C416

R610

R866

Q915

R831

R834

R705

Q803

Q922

R407

R832

D809

Q902

R841

R825

R933

R420

D912

R910

Q905

R909

R932

C807

R905

C705

R703

R815

R611

R829

R904

C710

R824

JR701

R618

R818

R606

R809

R801

C704

R408

R846

D907

C612

C709

C609

R406

R403

R931

IC803

C620

R914

D918

R811

Q903

R802

R836

R849

R860

R859

R858

R857

R856

R855

R838

R820

D819

Q921

R837

D802

Q919

Q913

R808

C811

R830

IC802

C905

C902

D601

JR903

C419

R414

R623

C630

JW139

JW52

R916

JW21

JW87

JW115

D911

JW40

JW121

JW132

JW72

JW143

JR804

JW80

JW133

JW53

JW94

JW12

IC401

CNP901

F901

L900

JW64

D903

R917

TH901

R921

JW29

C901

JW93

D915

JW20

R926

CNJ801

JW116

JW114

R804

D917

JW86

JW92

JW147

TH900

JW18

JW14

R922

CNP701

TU601

JW49

C614

JW24

JW25

C701

JW112

JW95

D916

JW136

JW17

Q912

JW104

JW3

C907

JW16

D910

JW38

R913

JW68

D813

D817

D815

C804

C912

JW141

C404

JW66

D801

JW119

JW81

JW2

JW9

JW73

JW127

C412

JW85

CNP802

JW142

JW131

JW48

JW1

JW82

JW84

D926

D927

JW42

Q906

JW98

PJ601

JW7

JW50

C917

X801

JW130

X802 JW46

D909

JW6

X601

JW118

JW101

JW113

D816

D814

JW120

R624

JW74

JW11

JW96

JW54

JW62

C402

JW79

R847

JW110

JW103

JW136

JW123

JW13

D904

D901

JW30

JW10

JW129

JW23

PJ401

R924

JW56

JW61

R411

R919

D914

JW122

JW77

R405

C608

D811

JW109

JW105

JW99

JW146

C403

JW149

JW76

JW65

JW107

JW83

R935

C401

JW97

JW15

C706

C411

JW22

C909

JW27

R845

JW75

C712

JW108

JW63

JW44

JW32

C806

S801

R918

JW47

R920

JW100

R903

JW8

JW78

JW111

JW36

D902

JW5

JW19

JW89

JW106

JW102

JW58

JW117

D919

JW33

JW28

JW70

JW37

JW4

JW34

JW69

JW91

C816

JW41

JW39

R927

JW45

JW43

JW145

R848

JW88

JW135

JW90

JW55

JW35

D905

JW26

C920

D812

JW51

D908

JW148

JW31

JW71

JW67

CNP801

JW59

D807 JR803

JW60

JW144

JW201

JW202

JW204

JW208

JW203

JW207

JW205

JW206

AEP/UK MODEL

E MODEL

(Page 24)

3-8. PRINTED WIRING BOARD —MAIN SECTION —•Refer to page 17 for Circuit Boards Location.

(Page 19)

Q602 H-3

Q801 H-9

Q803 I-9

Q901 E-6

Q902 D-6

Q903 E-7

Q904 C-5

Q905 C-5

Q906 G-10

Q907 G-9

Q908 F-10

Q909 E-9

Q910 E-9

Q911 F-2

Q912 C-10

Q913 E-7

Q914 E-8

Q915 G-9

Q916 F-8

Q917 E-9

Q918 H-10

Q919 I-10

Q920 E-10

Q921 F-10

Q922 F-8

D911 D-8

D912 C-8

D914 D-8

D916 E-6

D917 G-10

D918 E-2

D919 F-2

D921 D-5

D922 E-5

D925 G-9

D926 C-10

D927 F-7

IC401 B-6

IC402 E-3

IC601 H-3

IC602 H-2

IC801 H-7

IC802 I-9

IC803 F-9

Q401 C-4

Q402 C-3

Q403 C-3

Q404 C-4

Q601 H-1

D601 H-2

D602 H-2

D801 H-9

D802 H-9

D804 E-9

D805 E-9

D806 D-9

D807 I-9

D809 I-3

D811 I-4

D812 I-4

D813 I-2

D814 I-2

D815 I-2

D816 I-2

D817 I-2

D901 D-6

D902 D-6

D903 D-6

D904 D-6

D905 C-5

D906 B-7

D907 B-7

D908 C-5

D909 D-8

D910 D-8

•Semiconductor Location

Ref. No. Location Ref. No. Location Ref. No. Location

2222

CDX-CA600/CA600X

IC B/D

AEP/UK MODEL

E MODEL

D917

R413R414

R415

R416

R417

R601

IC401

L900

C901

R930

Q909

C701

R605

IC402

R412

R701

C907

R925

R913

C404

R410

C412

Q906

R934

R911

R409

D909

R604

R923

R901

R418

R704

R419

R907

C402

JR901

R924

R906

R411

R405

C403

Q922

R407

C401

C706

R420 C411

D912

R910

R909

R932

C909 R905

R703

R606

R408

R623

R406

C905

R602

R603

R922

D915

R935 R931

C601 C602

C610

C609

C918

C702

C704

C613

C612

C611

C707

C708

C709

C710

C705

C421

C420

C419

C418

C416

C405

C406

C407

C408

C409

C912

TH901

C417

R908

D916

C703

D919

C607

C604

R618

C631

R613

C627

C630

R614

R616

C628

C626

R615

R617

R619

C632

C633

C634

R620

D602

R621

C906

D922

R933

D914

C625

C624

C622

C621

R612

C620

R611

R610

C619

C618

C617

X601

C615 C616

R607

R608

PJ601

R609

C614

PJ401

R403

R404

R402

R401

C623

C608

C920 C917

TU601

Q601

IC602

R624

D601

Q602

IC601

Q401

Q402

Q403

Q404

Q904

Q905

D921

R903

F901

CN901

C902

D911

Q920

Q921

Q917

Q903

Q907

Q908

Q910

D918

D910

Q911

Q902 Q901

D908

D901

D902

D903

D904

D905

D907

D906

R904

1SR154-400TE-25

•Refer to page 17 for Waveforms.

3-9. SCHEMATIC DIAGRAM —MAIN SECTION (1/2) —•Refer to page 26 for IC Block Diagrams.

(Page 23)

Note:

• Voltage is dc with respect to ground under no-signal

(detuned) condition.

no mark : FM

( ) : MW/LW

< > : CD PLAY

23 23

CDX-CA600/CA600X

D926D927

Q912

Q916

R807

R914

R805

R828

R819

R814

R813

R835

D813

D817

D815

JR703

C804

R817

R823

C803

R867

D816

D814

R812

R866

R806

R915

D811

R825

C712

R815

R829

R818

R801

IC803

R802

R820

R927

R808

D812

R830

FB801

R822

R821

R837

D801

C812

C809

C808

C810

C811

TH900

R816

C815

CNP802

R916

R917

R918

R919

R921

R920

R824

CNP701

R842

R705

R849

R850

R851

R852

R853

R856

R855

R854

R857

R858

R848

R847

R846

R859

R860

D819

C816

R868 R869

R836

R832R831

X802

R838

R839

R840

R841

D820

C802

C801

R926

R826

R827

Q918

S801

CNJ801

CNP801

C814

JR701

R834

R833

R809

R810

D802

R845

X801

C807 IC802

R811

Q913

Q914

Q915

D925

IC801

C806

Q801

D804

D805

D806

JR903

Q803

D807

D809

Q919

JR804 R804

JR803

3-10. SCHEMATIC DIAGRAM —MAIN SECTION (2/2) —•Refer to page 17 for Waveforms.

Note:

• Voltage is dc with respect to ground under no-signal

(detuned) condition.

no mark : FM

( ) : MW/LW

< > : CD PLAY

(Page

20)

(Page 25)

(Page 22)

25 25

CDX-CA600/CA600X

JR504

C502

IC501

JR501

JR502

JR503

JR508

JR510

JR513

JR515

R501 R502 R503 R504 R505 R506 R507 R508 R509 R510

R511 R512 R513 R514 R515 R516 R517 R518 R519 R520 R521

R553

R555

R556

R557

R558

R559 R560

S501 S502 S503 S504 S505 S506 S507 S508 S509 S510

S511 S512

S513

S514 S515 S516 S517 S518 S519 S520 S521

R565

R566

R568

R567

R570

R569

R572

R571

R574

R573

R576

R575

R577

R578

R579

R580

LED549

LED550

CNP551

JR516

JR514

R554

C501

C503

IC552

CNP552

JR505

JR509

D501

R564

R563

R562

R561

R552

R525

R524

R523

R522

JR512

D561

D562

D563

D564

D565

D566

R584

R583

D567

D568

D569

R586

R585

D570

D571

D572

R588

R587

D573

D574

D575

R590

R589

D576

D577

D578

R592

R591

D579

D580

D581

R594

R593

D582

D583

R596

R595

D584

JR518

D585

R598

R597

D586

D587

D588

D589

R599

R582

R581

JR517

JR520 JR507JR506

JR511 JR519

D506

LCD501

D502

D503

D531

D532

D533

D536

R551

D545 D544 D543

D548 D547 D546

D551 D550 D549

D554

D557

Q503

Q502

D504

D505

R526

Q501

D534

D535

D537

D538

D539

D540

D541

D542

D552

D553

D555

D556

D558

D559

R550

3-12. SCHEMATIC DIAGRAM —DISPLAY SECTION —

Note:

• Voltage is dc with respect to ground under no-signal

(detuned) condition.

no mark : FM

(Page 23)

Andere Handbücher für CDX-CA600

Dieses Handbuch passt für folgende Modelle

Inhaltsverzeichnis

Andere Sony Autoempfänger Handbücher

Sony

Sony Xplod CDX-GT250MP Bedienungsanleitung

Sony

Sony CDX-L410X - Fm/am Compact Disc Player Bedienungsanleitung

Sony

Sony CDX-GT260MP Bedienungsanleitung

Sony

Sony MEX 1GP - Giga Panel Radio Bedienungsanleitung

Sony

Sony CDX CDX-GT23 Bedienungsanleitung

Sony

Sony CDX-GT45IP Bedienungsanleitung

Sony

Sony XR-3500MK2 Bedienungsanleitung

Sony

Sony HCD-DR4 Bedienungsanleitung

Sony

Sony CDX-GT414U Bedienungsanleitung

Sony

Sony XR-C453RDS Bedienungsanleitung

Sony

Sony XAV-65/C1 Bedienungsanleitung

Sony

Sony CDX-C4840R Bedienungsanleitung

Sony

Sony MEX-DV1000 - Cd/dvd Receiver, Mp3/wma Player Produkthandbuch

Sony

Sony CDX-GT570UI Produkthandbuch

Sony

Sony XAV-68BT Bedienungsanleitung

Sony

Sony XAV-70BT Bedienungsanleitung

Sony

Sony CDX-GT606UI Bedienungsanleitung

Sony

Sony CDX-V7800X Bedienungsanleitung

Sony

Sony XR-C450 Produkthandbuch

Sony

Sony CDX-V3800 Bedienungsanleitung

Sony

Sony CDX-L510X - Fm/am Compact Disc Player Bedienungsanleitung

Sony

Sony CDX-3002 Bedienungsanleitung

Sony

Sony XR-CA650X - Fm-am Cassette Car Stereo Bedienungsanleitung

Sony

Sony CDX-R3000 - Fm/am Compact Disc Player Bedienungsanleitung

Beliebte Autoempfänger Handbücher anderer Marken

Motorola

Motorola VWA63 Bedienungsanleitung

Nextar

Nextar D3201 Bedienungsanleitung

Alpine

Alpine CDE-163BT Bedienungsanleitung

Pioneer

Pioneer DEH-P645R Bedienungsanleitung

Axxera

Axxera XDMA7600 Betriebsanleitung

XM OnyX Bedienungsanleitung

Sound Storm

Sound Storm STM93R Bedienungsanleitung

Soundstream

Soundstream VIR-5000 Bedienungsanleitung

Avson

Avson MKT Platform Bedienungsanleitung

Pioneer

Pioneer DVH-P500UB Bedienungsanleitung

JVC

JVC KD-AHD69 Bedienungsanleitung

Blaupunkt

Blaupunkt SANTIAGO CR 87 Bedienungsanleitung

XFIRE AUDIO

XFIRE AUDIO BMW42S Bedienungsanleitung

VDO

VDO CD 2253 Bedienungsanleitung

Volvo

Volvo 13 84 580 Bedienungsanleitung

ZENEC

ZENEC ZE-160DVD Bedienungsanleitung

Medion

Medion Car Audio Bedienungsanleitung

Philips

Philips CEM5000 Bedienungsanleitung