Kenwood KAC-6404 User manual

This product uses Lead Free solder.

This product complies with the RoHS directive for the European market.

B53-0606-00 (N)519

SERVICE MANUAL

KAC-6404/7404

KAC-M645/M845

POWER AMPLIFIER

Accessories

(W01-1606-05)

Screw & wrench key set

(N99-1587-15)

Connecting cord assy

(E30-6144-05)

19cm

FUSE [40A] P.CON

POWER IN

BRIDGED

SPEAKER OUTPUT

LEFT RIGHT

BATT.

LINE IN

LPF FREQUENCY[Hz]INPUT SENSITIVITY[V]

[MIN] [MAX]

OFF LPF

B ch FILTER

SPEAKER

LEVEL INPUT

OFF LPF

A ch FILTER

A ch

[MIN] [MAX]

B ch B ch

4/3/2 Channel

MAXIMUM

Power Amplifi er

POWER

4/3/2 Channel

MAXIMUM

Power Amplifier

POWER

4/3/2 Channel

Power Amplifi er

MAXIMUM

POWER

4/3/2 Channel

MAXIMUM

Power Amplifier

POWER

4/3/2 Channel

MAXIMUM

Power Amplifier

POWER

FUSE [25A]

KAC-7404(E type)

KAC-6404(K type)

KAC-M645(M type)

KAC-6404(E type)

KAC-M845(M type)

KAC-6404/M645KAC-7404/M845

KAC-7404/M845:Fuse (40A):(F52-0016-05)

KAC-6404/M645:Fuse (25A):(F52-0014-05)

KAC-6404/7404/M645/M845

BLOCK DIAGRAM

H.P.F

(80Hz/-12dB)

L.P.F

(50

200Hz

-12dB)

H.P.F

ON /OFF.

ISO-

AMP

ISO-

L+

L-

R-

R+

L+

L-

R-

R+

SENS.

VOL

SENS.

VOL

H.P.F

(80Hz/-12dB)

OU TPU T

MUTEATT

POWER AMP

(INV)

MUTEATT

POWER AMP

OU TPU T

MUTEATT

POWER AMP

(INV)

MUTEATT

POWER AMP

BATT.

GND

P-CON

THERMAL

DET

DC-OFFSET

DET

POWER

ON/OFF

DC/DC

CON

FAN

AVR

FAN

LC FILTER

±15V

AVR

OVERLOAD

±B

AMP

L.P.F

ON /OFF

DET

IC1,2

IC3,4

IC9

IC8

IC7

IC5

Q127,131

Q128 ,132

Q227 ,231

Q228 ,232

Q101

Q102

Q201

Q202

Q103-125

Q104-126

Q203-225

Q204-226

TH3,IC10

Q611-614

Q610

Q3,4 D4,5 IC13 Q1,2,5-12

Q604 ,605

Q607 KAC-7404

only

KAC-6404/7404/M645/M845

●AUDIO UNIT (X09-8722-70/2-71)

Ref. No. Application / Function

IC1-4 Isolation circuit

IC5 LPF Phase inversion

IC7 HPF

IC8,9 Buffer ampliﬁer

IC10 Temperature detection comparator

IC13 DC/DC converter

Q1,2,5,6 DC/DC converter power driver

Q3,4 Constant voltage circuit (±15V) power driver

Q7-10 DC/DC converter gate driver

Q11,12 DC/DC converter control

Q101,102,201,202 Signal mute

Q103-106,203-206 Differential ﬁrst stage ampliﬁer

Q107-110,207-210 Differential second stage ampliﬁer

Q111,112,211,212 Differential second stage current mirror

Q113,114,213,214 Idling temperature detection

Q115-118,215-218 Current limiter

Q119-122,219-222 Power ampliﬁer driver

Q123-126,223-226 Power ampliﬁer ﬁnal

Q127,128,131,132,227,228,231,232 Protector ATT

Q601 Shock noise prevention circuit control

Q602,603 Mute circuit control

Q604-606 P-Con control

Q607 FAN power supply drive

Q610 Over current detection

Q611-614 DC protector control

Q615-618 Shock noise prevention circuit control

COMPONENTS DESCRIPTION

KAC-6404/7404/M645/M845

ABCDE

AUDIO UNIT X09-8722-70/2-71 (J76-0469-01)

IC13

Q120

Q219

Q122

Q222

Q604

Q607

Q118

Q218

Q124

Q223

Q126 Q226

CN1

Q1 Q2

Q5 Q6

D33

D604

D609

D610

D616

Q10

Q602

Q605

Q606

D108

D110

D207

D210

D211

D601

D602

D603

D605 D606

D607

D608

Q11

Q12

Q116

Q215

Q601

Q603

Q618

D615

Q114

FAN

W166

W167

W151

C601

C602

C603

C604

C611

C612

C16

R254

R256

R453

R616

W152

W165

W153

W174

W162

W141

W142

W144

W143

W189

W140

W137

W158

W134

W130

W136

W139

W135

W132

W133

W160

W183

W116

W117

W129

W127

W114

W125

W172

W176

W124

W149

W161

W163

W131

W123

W179

W155

W177

W154

W178

W147

W150

W111

W128

W156

W138

W118

W185

W184

W173

W119

W181

W182

W164

W188

W190

W191

W121

W180

W175

W120

W159

W148

W146

W113

W126

W122

W112

W145

C28

W157

W199

W193

W200

W197

W196

W169

W104

W201

W202

W203

W168

W171

W170

W198

W186

W187

C29

C10

C11

C25

C26

916

R608

R609

R619

R668

R602

R625

C15

C617

R10 R11

R16

R17

R606

R613

R614

R670

TH3

C14

C218

C220

C222

C419

C422

R3 R4

R12

SDG SDG SDG SDG

R13

R14

R15

R18

R20

R21

R22

R24

R25

R28

R230

R232

R234

R236

R238

R240

R242

R244

R246

R248

R250

R252

R429

R433

R435

R438

R439

R442

R445

R448

R449

R452

R601

R603

R604 R605

R607

R610

R611

R612

R615

R624

R626

R631

R660

R667

R671

W592

W591

W585

W584

W581

W580

W583

W579

W576

W577

W57

W575

W573

W590

W589

W588

W574

W586

W587

W582

W596

C424C224

R458

C223

R258

R272

W600

R627

R23

C423

C12

R457

R25

BE BE BE

BE B

BE BE

TP358

TP359

TP62

TP46

TP48

TP50

TP52

TP368

TP39

TP40

TP41

TP42

TP43

TP45

TP47

TP49

TP51

TP53

TP54

TP55

TP56

TP61

TP356

TP365

TP379

TP394

TP399

TP400

TP401

PC BOARD (FOIL SIDE VIEW)

Refer to the schematic

diagram for the values

of resistors and capaci-

tors.

X09-8722-70/2-71

Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address

IC1 4I IC8 5H Q3 6H Q9 2E Q103 3H Q109 3H Q115 2H Q121 2I Q127 4H

IC2 4H IC9 5I Q4 6H Q10 3E Q104 4G Q110 5F Q116 5D Q122 6C Q128 4G

IC3 4H IC10 3F Q5 2C Q11 3E Q105 3H Q111 3H Q117 2I Q123 2G Q131 4H

IC4 3I IC13 3E Q6 2D Q12 3E Q106 4G Q112 5F Q118 6C Q124 5D Q132 4G

IC5 5I Q1 2C Q7 2E Q101 3G Q107 3H Q113 2H Q119 2G Q125 2H Q201 3G

IC7 5H Q2 2C Q8 3E Q102 4G Q108 5F Q114 6D Q120 5D Q126 5C Q202 4G

KAC-6404/7404/M645/M845

JIHGF

IC1

IC2

IC3

IC4

IC5

IC7

IC8

IC9

IC10

IC13

Q119

Q219

Q220

Q121

Q221

S1S2

Q107

Q108

Q109

Q110

Q111

Q112

Q117

Q207

Q208

Q209

Q210

Q211

Q212

Q217

Q123

Q224

Q125

Q225

Q226

CN2

D34

D36

D35

D37

Q610

D610

D614

D616

Q101

Q102

Q127

Q128

Q131

Q132

Q201

Q202

Q227

Q228

Q231

Q232

Q611

Q612

Q613

D32

D10

D11

D101

D102

D103

D104

D105

D106

D107

D109

D111

D201

D202

D203

D204

D205

D206

D207

D208

D209

D211

D613

Q103

Q104

Q105

Q106

Q115

Q203

Q204

Q205

Q206

Q216

Q614

Q615 Q616

Q617

Q618

Q213

Q113

Q214

BchAch

GAIN GAIN

LPF

FREQ

OFF HPF OFF LPF

FAN

C22

C27

C616

C606

C18

C207

C208

C407

C408

R100

C13

C16

C103

C104

C111

C112

C113

C114

C115

C116

C155

C156

C159

C160

C201

C202

C303

C304

C311

C312

C313

C314

C315

C316

C327

C328

C355

C356

C401

C402

R101

R102

R253 R255

R301

R302

R454

R455

R456

W80

W116

W117

W88

W100

W114

W89

W97

W98

W86

W90

W84

W92

W85

W87

W69

W74

W111

W99

W103

W83

W82

W41

W77

W42

W23

W102

W45

W10

W11

W51

W29

W28

W118

W60

W14

W17

W39

W38

W13

W119

W30

W35

W32

W43

W12

W53

W31

W34

W192

W21

W20

W37

W36

W46

W50

W26

W22

W27

W24

W25

W57

W48

W115

W79

W76

W52

W66

W65

W108

W81

W15

W93

W58

W121

W54

W40

W68

W62

W120

W105

W18

W96

W113

W94

W106

W107

W19

W122

W110

W55

W73

W112

W63

W64

W109

W95

W61

W16

W70

W67

W33

W71

W47

W44

W78

W56

W59

W72

W75

W49

W101

W194

W195

W91

W204

C225

C608

ALBL

VR1

VR2 VR3

W540

W531

W539

W501

W500

C20

C23

C31

C33

C35 C42

C44

R31

R207

R208

R407

R408

R223

R224

R225

R226

R423

R424

R425

R426

R668

C21

C24

C32

C34

C36

C41

C43

R659

R261

R629

R666

R669

R618

C19

C117

C118

C203

C204

C317 C318

C351

C403

C404

C609

C610

C617

W597

R19

R26

R27

R35

R36

R39

R115

R116

R153

R155

R156

R167

R168

R179

R180

R181

R182

R203

R204

R205

R206

R315

R316

R319 R320

R327

R328

R335

R336

R355

R356

R367

R373

R403

R404

R405

R406

R635

R636

R661

R662

R663

R664

R670

C101

C102

C301C302

R103

R104

R107

R108

R113

R114

R303

R304

R307

R308

R313

R314

C14

C105

C106

C107

C108

C109

C110

C128

C150

C151

C152

C153

C154

C217

C219

C221

C259

C260

C305

C306

C307

C308

C309

C310

C352

C353

C417

C418

C420

C421

C459

C460

C607

C227

C228

C425

C426

W598

R20

R21

R22

R28

R32

R33

R34

R37

R38

R105

R106

R109

R110

R111

R112

R117

R118

R121 R122

R123

R124

R125

R126

R151

R152

R154

R165

R166

R201

R202

R209

R210

R211

R212

R213

R214

R215

R216

R217

R218

R219

R220

R221

R222

R229

R231

R233

R235

R237

R239

R241

R243

R245

R247

R249

R251

R259

R260

R265

R266

R267

R268

R269

R270

R305

R306

R309

R310

R311

R312

R317

R318

R321 R322

R323

R324

R325

R326

R357

R358

R359

R360

R361

R362

R374

R379

R380

R401

R402

R409

R410

R411

R412

R413

R414

R415

R416

R417

R418

R419

R420

R421

R422

R429

R430

R431

R432

R433

R434

R435

R436

R437

439

R440

R441

R443

R444

R445

R446

R447

449

R450

R451

R459

R460 R465

R466

R467

R468

R469

R470

R617

R620

R621

R622

R623 R632

R633

R634

R637

R665

R667

W537

W541

W523

W578

W576

W572

W571

W573

W508

W570

W562

W569

W574

W554

W568

W551

W542

W558

W507

W509

W521

W526

W504

W502

W514

W529

W517

W512

W511

W503

W560

W505

W513

W543

W506

W545

W547

W557

W533

W520

W593

W510

W516

W519

W567

W538

W535 W528

W525

W527

W561

W555

W563

W553

W530

W534

W548

W536

W549

W524

W515

W518

W522

W546

W564

C605

W552

W532

W565

W544

W556

W559

W550

R271

W594

C17

C411

R427

C209

R472

C409

W595

R227

C413

C406

C211

C410

C229

C214

C206

C205

C427

C405

C412

C212

C213

C414

C230

C428

R471

W599

W600

R228

R428

C216

C416

C215

C415

C100

C210

R29

R30

W566

C37

C30

BE BE

BEBE

EBE

BE BE

BEBE

BE BE

EB EB EB

TP57 TP60

TP24

TP121

TP23

TP29

TP30

TP31

TP32

TP37

TP38

TP42

TP44

TP58

TP59

TP63

TP64

TP65

TP66

TP67

TP69

TP71

TP72

TP73

TP74

TP76

TP77

TP78

TP79

TP80

TP81 TP82

TP85

TP86

TP87

TP120

TP122

TP242

TP246

TP251

TP253

TP255

TP356

TP360

TP362

TP364

TP366

TP367

TP369

TP370

TP371

TP372

TP373

TP374

TP375

TP376

TP377

TP378

379

TP380

TP381

TP391

TP392

TP393

TP394

TP395

TP396

TP397

TP398

TP25

Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address Ref. No. Address

Q203 3G Q209 3G Q215 2E Q221 2G Q227 4G Q603 4C Q611 4F Q617 4F

Q204 4G Q210 5G Q216 5F Q222 5E Q228 4G Q604 4C Q612 4F Q618 4F

Q205 3G Q211 3G Q217 2G Q223 2E Q231 4G Q605 4B Q613 4F

Q206 4G Q212 5H Q218 5E Q224 5G Q232 4G Q606 4B Q614 4F

Q207 3G Q213 2F Q219 2F Q225 2F Q601 4C Q607 6B Q615 5F

Q208 5H Q214 6F Q220 5F Q226 5E Q602 4C Q610 4F Q616 5F

KAC-6404/7404/M645/M845

X09-8722-70/2-71 (1/4)

ABCDE

-1

(X09-8722-7x)

Q107-110,207-210

217,218

Q604

Q607

Q125,126,225,226

Q111,112,117,118,211,212,

Q113,114,213,214

Q119,120,219,220

Q121,122,221,222

Q123,124,223,224

D2,3

D604,614

D606

D607

D609

D610

D32

D6,34,36,105,111,205,211

D7-11,101-104,107-110,

201-204,207-210,601-603,

605,608,613,615,616

D35,37,106,206

D1,33

D37

IC3

(1/2)

IC3

(2/2)

D36

(1/2)

IC4

(2/2)

: UMZ6.8N

UDZS10B

UDZS15B

UDZS6.8B

UDZS12B

B30-1743-05

LM1MA142WA-G

UDZS16B

FCH10A20

FRH10A20

1SS355

LM1MA142WK-G:

∗

2SB1241

2SD1863

1N5406-TSC

2SA817A-F

2SC1627A-F

2SC4081(S)

2SC1845-A(F,E)

2SA992-A(F,E)

IC13

Q9,10

Q7,8,602

Q1,2,5,6

Q11,12

IC1-5,7-10

Q101,102,115,116,127,128,

131,132,201,202,215,216,

227,228,231,232,605,606,

610-613,616,618

Q103-106,203-206,601,

603,614,615,617

D32

LINE IN

D35

(1/2)

IC1

(2/2)

D34

: DTA114EUA

2SC4081

2SA1576A(R,S):

BA4560RF

TL494IDR

2SA1577

2SD2012-F

2SB1375-F

2SC4097

STP60NF06FP:

IC2

(1/2)

IC2

(2/2)

Ach INPUT SE

Bch INPUT SE

(X09-8722-7X)

SIGNAL LINE

B LINE

GND LINE

ISO

C302

1000P

C301

1000P

R310 12K

R306

4.7K

C306

15P

R304

10K

R303

10K

R308

10K

R307

10K

R312

10K

R316

10K

C318

100P

C308

15P

R309 12K

C305

15P

R305

4.7K 5

R311

10K

C307

15P

R315

C317

100P

10K

SP INPUT

R321

100K

2.2K

R323

R325

100K

R322

2.2K

R326

100K

R324

10u50

C313

C315

10u50

C316

10u50

C314

R121

2.2K

R122

2.2K

R124

100K

R126

100K

R125

100K

R123

100K

C114

10u50

C116

10u50

C115

10u50

C113

10u50

R319

47K

C312

47u25

R318 10K

C310 100P

C34 0.01 C33 0.01

C309 100P

R320

47K

R317 10K

85 7

C311

47u25

VR2 10K 10

R15

VR1 10K 10

C108

15P

R101

R102

C128

0.01

R100

C100

1000P

C106

R106

4.7K

15P

3R112

10K

C107

15P

10u50

C104

R108

10K

C103

10u50

R107

10K

TP64

R114

10K

R116

C118

100P

10K

R113

R115

C117

100P

10K

R105

4.7K

57R111

10K

1/2W

C112

47u25

C32

0.01

C31

C111

47u25

1/2W

1500P

TP73

TP74

TP67

TP66

TP69

15P

C105

C109 100P

R117 10K

R118 10K

C110 100P

R109 12K

R110 12K

TP71 TP72

TP65

TP63

TP81

TP79

TP80

TP77

TP76

TP78

TP87

TP85

TP86

TP82

10K

R314

10K

R313

TP31

TP32

TP29

TP30

TP25

TP24

TP23TP120

TP122

TP121

10u50

C304

10u50

C303

R302

R301

1000P

C101

1000P

C102

10K

R103

10K

R104

MODEL C6,7,

YES

D33

YES

28,29

C25,26,

YES

KAC-6404

KAC-M645

KAC-M845

KAC-7404 2-70

2-71

UNIT

No.NAME 10,11

YES

L1-3

YES

L4,5

YES

Q5,

2SC4468NF

223,224

Q123,124,

2SC4467NF 2SA1694NF

2SA1695NF

225,226

Q125,126,

421,422415,416

4.7K

6.8K

R215,216, R221,222

R5,6

3.3K

2.7K 5.6K

10K

R23 449-452

620

1.5K

R249-252,

1.2K

R608,

619

5.6K

4.7K1.5K

R12,

YES

668

15K

22K

R666,

15V

+15V

15V

+15V

KAC-6404/7404/M645/M845

X09-8722-70/2-71 (2/4)

JIHGF

2-71 : -24.7V

2-70 : -35.5V

2-71 : +24.7V

2-70 : +35.5V

5.0V

-15.0V

15.0V

2.5V

IC13

Q128

Q228

Q227

Q127

(2/2)

IC9

(2/2)

IC8

IC9

(1/2)

IC8(1/2)

(2/2)

IC5

(1/2)

IC7

(1/2)

(2/2)

IC7

D3 D2

Q3 D4

∗Q6

Q12

IC10

(1/2)

∗Q5

Q10

Q11

D11

Q231

Q232

Q132

Q131

D10

INPUT SENS.

PHASE INVERTER

HPF : 80Hz.12dB/OCT

LPF

50-200Hz

PHASE INVERTER

OFF/LPF

OFF/HPF

-3.0dB

-1.5dB

-3dB ATT

ATT -1.5dB

ATT -3.0dB

DC/DC CONVERTER

TEMPERATURE DET

C17

1000P

R402

3.3K

TP255

R380

10 2

C24

R2 10K 10

R379

R151

TP253

R152

10K

C150 47P

R154 10K

C35 0.01

C36

0.01

R1 10K 10

C328

10u50

C355

10u50

C327

10u50

R357

39K

R361

R358

39K

VR3

0.01

4.7K

R367

C41

10K

0.01

R360

10K

R359

68K

C353

0.047

C351

0.1

C352 47P

R374 10K

R336

47K

R335

47K

R373

47K

R362

10K

R417

13K

R401

3.3K

C44

C43

R166

0.1

15K

0.1

TP251

C152 C154

R168

27K

10u50

C160

10u50

R182

47K

C156

C153C151

R165

0.1

15K

0.1

R167

27K

8C155

0.01

R181

47K

10u50

C159

10u50

R180

47K

R202

3.3K

R218

13K

R179

47K

3.3K

R217

13K

R201

1/2W

47u25

10u50

47u25

10u50

∗C28

2200u35

∗C29

2200u35

∗R5

1/2W

∗L2

3300u16

∗C11

∗C10

1/2W

∗L5

2200u16

∗C25

∗C26

R15

3300u50

∗C7

3300u50

∗C6

TH3

∗R13

C19

0.1

R36

R32

200

C21

0.01

C20

0.01

470K

100

R33

C15

0.1

10u50

C18

R11

4.7K

R10

4.7K

∗R12

R14

R16

1.5K

R17

1.5K

R19

33K

C13

10u50

TP356 TP401

R20

330K

R21

C14

0.01

10K

R25

R26

R27

22K

4.7K

R22

3.3K

C16

47u25

R467

10K

R468

10K

R466

10K

R465

10K

C30

0.01

10K

16K

R270

R260

R268

10K

C37

0.01

16K

10K

R259

R269

R267

10K

R38

5.6K

R30

100

R261

R659

18K

C616

10u50 TP

E1C1

2.2K 2.2K

R39 R35

R34

5.6K R29

100

C27

10u50

100 R266

10K

R265

10K

OUTCTRL

DTC

GND

FBACK

IN1-

IN1+

VCC

REF

IN2-

IN2+

430

R355

430

R356

R327 10KR328 10K

C42 0.01

C23 0.01

10u50

C356

430

R155

430

R156

R153 10K

R37 470K

∗R23

∗R6

TP359

TP358

R28 100K

R24 10K

R18 33K

C12 1500P

10K

R459

16K

R469

10K

R460

16K

R470

13K

R418

10u50

C22

10K

R31

C22

TP242

TP246

TP60

TP57

+15V

15V

15V +B

15V

+15V

15V

+15V

15V

+15V

15V

+15V

BU BU

SW12V

KAC-6404/7404/M645/M845

X09-8722-70/2-71 (3/4)

KLMNO

Q204

Q206

D204

Q220

Q214

Q212

D208

Q216

∗Q224

Q202

Q208

D202

D201

Q203

Q201

Q207

Q205

D203

Q106

D104

Q221

Q210

D206

Q218

D210

D211

Q213

Q209

D205

Q211

D209

Q217

Q215

Q222

∗Q226

∗Q225

Q219

Q120

D207

Q114

Q112

D108

Q116

∗Q223

∗Q124

Q610

Q602

D610

D608

D601

D60

Q104

Q102

Q108

D102

Q103

Q101

D101

Q107

Q105

D103

Q122

Q121

Q110

D106

Q118

D111

D110

Q109

D105 Q117

D109

∗Q126

∗Q125

Q119

Q113

Q111

D107

Q115

∗Q123

Q601

AL POWER AMP

AR POWER AMP

BL POWER AMP

BR POWER AMP

MUTE

OVER

DET

CURRENT

C422

1000P

R442

C418

0.01

R432

560

∗R416

R414

C402

10u50

470P

R430

1.8K

C410

R434

C416

R428

47K

R472

100

R436

C420

1000P

R440

150

R407

15K

R410

R466

10K

R406 47K

C404 470P

R409

R420

R412

1.5K

C406

4700P100

C412

100P

R411

1.5K

R419

R465

10K

C403 470P

R405 47K

TP362

C401

10u50

C405

4700P

TP374

TP375

R413

100

TP373

TP61

R208

15K

R224 ∗R222

R429

1.8K

∗R452

R437

100 100

100

R438

100

C425

560

R431

R427

47K

R471

R441

R439

R448

4.7

470P

C409

100

R435

470P

R226

150

C210

R234

R236

100

C220

1000P

R240

R445

4.7

R254

0.1

12K

R629

C606

100u10

10K

R617 TP381

R632

47K

C601

C612

10u50

33u35

R603

R219 150

R220

∗R221

R206 47K

C204 470P

R266

10K

R210

4700P

∗R216

R214

100

C206

R212

1.5K

R265

10K

R209

C203 470P

R205 47K

C201

10u50

R211

1.5K

C205

4700P

R213

100

∗R215

R223

R207

15K

∗R252

C230

100P

C216

R228

47K

C214

100P

100

C222

1000P

R242

R238

100

C227

C215

R227

47K

R231

560

C217

0.01

R241

R239

R256

0.1

R248

4.7

R631

R255

0.1

R253

0.1

∗R249

R225

150

C209

470P

R235

100

R660

10K

R602

1.2K

R604

R626

22K

TP391

1000P

C421

1000P

C419

470

R443

0.1

R455

0.1

R453

∗R451

4.7

R447

∗R449

R433

C417 0.01

C415 5P

∗R421 150

R423

150

R425

100P

C427

47P

C459

100P

C413

100K

R403

47u25

C407

∗R415

100K

R404

∗R422

C426

15K

R408

47P

C460

150

R424

150

R426

100P

C414

100P

C428

100P

C411

470

R444

∗R450

0.1

R454

0.1

R456

TP367

TP43

TP42

TP366

TP44

TP41

TP378

TP376

TP377

TP360 TP58

TP59

TP369

TP371

TP370

TP372 TP365

TP40

TP364

TP38

TP37

1.8K

R229

R271

R233

1000P

C219

470

R243

4.7

R245

1000P

C221

100

R237

560

R232

R272

1.8K

R230

TP39

470

R244

100P

C229

100P

C213

100P

C211 47u25

C207

47u25

C408

47P

C259

100K

R203

C228

100P

C21247u25

C208

100K

R204

10u50

C202

47P

C260

C218 0.01

4.7

R246

∗R250

∗R251

4.7

R247

4.7

R446

47K

R622

47K

R623

47K

R620

47K

R621

100u50

C225

SW12V

+B+B

BUBU

SW12

SW12VSW12V

KAC-6404/7404/M645/M845

X09-8722-70/2-71 (4/4)

TSRQP

14.4V

KAC-6404/7404/M645/M845

D615

D609

CN2

D616

Q607

Q615

Q617

Q616

Q618

Q611 Q612

CN1

D613

Q613

Q614

602

608

601

D602

D604

D614

D606

Q606

Q605

D607

Q603

D603

D605

Q601

Q604

∗D33

POP NOISE-MUTE

P-COM

UTE

DC PROTEC

FAN

+11V

FAN

∗A

10u50

C604

R625

680

C611

TP399

10u50

C605

0.01

R670

R624

4.7

TP400

10K

C608

220u10

6.8K

C617

0.1

R671

47K

R635

6.2K

R636 R637

R632

47K

R618

2.2K

TP380

R634

12K

0.01

C607

R633

12K

TP396

C601

33u35

R603

C602

R606

10K

10u50

R607

4.7K

2.2K

C609

0.01

TP397

10K

C610

TP398

0.01

R613

1.5K

631

30K

R627

4.7K

R604

10K

R626

22K

R609

33K

R610

R611

3.6K 3.6K

R612

R615

3.9K

0.047

R457

R458

0.047

C424

0.047

C423

R257

10 1/2W

R258

C223

0.047

C224

18uH

∗L3

18uH

∗L1

∗L4

5uH

GND10

10u50

BR+

AR+12

BL-

AR-

BR-

AL-

AL+

BL+

P CON

C1 40A/25A

FUSE

BATT11

TP392

TP393

TP394

TP395

6.8K

R665

R661

R662

10K

R663

10K

R664

∗R666

6.8K

R667

33K

R669

TP391

TP53

TP52

TP51

TP48

TP49

TP46

TP50

TP368

TP45

TP47

10 1/2W

TP55

TP54

TP56

R605 33K

TP62

∗R619

∗R608

10u50

C603

3.3K

R614

3.9K

R616

R601 10K

TP379

∗R668

SW12V

CAUTION : For continued safety, replace safety critical

components only with manufacturer’s recommended parts

(refer to parts list).

Indicates safety critical components. To reduce the risk of

electric shock, leakage-current or resistance measurements

shall be carried out (exposed parts are acceptably insulated

from the supply circuit) before the appliance is returned to

the customer.

• DC voltages are as measured with a high impedance

voltmeter. Values may vary slightly due to variations be-

tween individual instruments or/and units.

2SA817A-F

2SA992-A

2SC1627A-F

2SC1845-A

2SA1576A

2SB1375-F

2SD2012-F

2SC4081

DTA114EUA

KAC-6404/7404/M645/M845

EXPLODED VIEW

Parts with the exploded numbers larger than 700 are not supplied.

φ2.6x13

φ3x10

φ2.6x8

φ3x6

φ3x8

φ3x14

φ3x10

M6 AU

M4 AU

: N09-6365-05

: N80-3010-43

: N82-2608-43

: N89-3006-43

: N89-3008-48

: N89-3014-48

: N09-6447-05

: N07-0003-08

: N09-4214-08

(X09-872)

J1 J2

VR3

VR2

VR1

Bundled to the

transistor.

Ax6

Ax4

Ax2

Yx2

Fx2

Zx4

Zx5

Gx2

Ax2

Ex3

Cx2

Fx2

Ex2

708

712

717

702

713

709

713

Bx3

709

ONLY USED

KAC-7404/M845

ONLY USED

KAC-7404/M845

ONLY USED

KAC-7404/M845

ONLY USED

KAC-7404/M845

ONLY USED

KAC-7404/M845

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