Cambridge Audio Azur 540-A Mk2 Service manual

1

540A V2

Issue Date: 31st March 2006

_________________________________________________________________________________________

SERVICE MANUAL

_________________________________________________________________________________________

SPECIFICATIONS:

Power Output 60W (into 8Ω)

90W (into 4Ω)

THD (unweighted) <0.002% @ 1kHz, of rated power
<0.070% 20Hz – 20kHz, of rated power
<0.025% 20Hz – 20kHz @ 10w

Frequency response (-1dB) 5Hz – 50kHz

S/N ratio (ref 1w) >85dB

Input impedances 47kohms

Power Amp damping factor >100

Max power consumption 650w

Min/On power consumption <35w (no signal)

Standby power consumption <10w

Bass / Treble controls Shelving, ultimate boost/cut + /-7.5dB
@ 20Hz and 20kHz

Dimensions 100 x 430 x 310mm
(3.9 x 16.9 x 12.2”)

Weight 7.4kg (16.3Lbs)

AP19973/1

Gallery Court Hankey Place London SE1 4BB UK

Tel: [phone] Fax: [phone]

2

540A V2.0 SERVICE MANUAL

TABLE OF CONTENTS

Safety Precautions & Important Notes

Exploded Diagram 4

Input PCB Schematic (Power Supply) 5

Input PCB Schematic (Buffers and Switches) 6

Input PCB Schematic (Tone Control) 7

Input PCB Schematic (Protection Circuitry) 8

Input PCB Schematic (Headphone Driver) 9

Input PCB Layout (Top Side) 10

Input PCB Layout (Bottom Side) 11

Input PCB Assembly BOM 12-13

Voltage Select Switch PCB Schematic 14

Voltage Select PCB Layout (Top Side) 15

Voltage Select PCB Layout (Bottom Side) 16

Voltage Select PCB Assembly BOM 17

Mains PCB Schematic 18

Front Panel PCB Schematic 19

Mains & Front Panel PCB Layout (Top Side) 20

Mains & Front Panel PCB Layout (Bottom Side) 21

Mains & Front Panel PCB Assembly BOM 22

Amp PCB Schematic (Right Channel) 23

Amp PCB Schematic (Protection) 24

Amp PCB Schematic (Power Amp) 25

Amp PCB Schematic (Left Channel) 26

Amp PCB Layout (Top Side) 27

Amp PCB Layout (Bottom Side) 28

Amp PCB Assembly BOM 29-31

Abus Module PCB Schematic 32

Abus Module PCB Layout (Top Side) 33

Abus Module PCB Layout (Bottom Side) 34

Abus PCB Assembly BOM 35

IC Pin Layout Details 36-42

3

SAFETY PRECAUTIONS & IMPORTANT NOTES

3

1. Check that the rear of the product indicates the correct supply voltage for
your area.

2. The lighting flash with the arrowhead within an equilateral
triangle is intended to alert the user or service agent to the
presence of dangerous voltages within the product enclosure that
may be of sufficient magnitude to constitute a risk of electric shock

to persons.

3. The exclamation point within an equilateral triangle is intended

to alert the user or service agent to the presence of important
operating and maintenance (Servicing) instructions in the literature
accompanying the appliance.

4. This product complies with EEC Low Voltage (73/23/EEC) and
Electromagnetic Compatibility (89/336/EEC) Directives when used and serviced
in accordance with this manual. For continued compliance all components
marked safety and EMC critical must only be replaced by Cambridge Audio
approved parts.

5. Any unauthorised design alterations or additions will void the manufacturer’s
warranty; furthermore the manufacturer cannot accept responsibility for personal
injury or property damage resulting therefrom.

6. When servicing, care should be taken to observe the original routing and
dressing of the leads and it should be confirmed that they have been returned to
normal after re-assembly.

Notes on chip component replacement

Never reuse a component that has been removed from a PCB
Notice that the minus side of a tantalum capacitor may be damaged by heat

COPYRIGHT NOTICE.

© 2005 Audio Partnership PLC. All rights reserved.

Cambridge Audio and Azur are registered trademarks for Audio Partnership PLC. This document
may not be reproduced, distributed, transmitted, displayed, published, or broadcast without the
express written prior permission of Audio Partnership PLC.
Alteration or removal of any trademark, copyright, or other notice from this content is prohibited.
Information provided in this document is provided solely for the use of official service agents in
repairing and servicing Audio Partnership PLC products.

Drawing ref AP Part Factory part number Description

To enhance viewing, please print to A3 4

1 PY687 6560-150001-000A VOLUME KNOB ALUMINIUM SKIN AP133601 SILVER (us e with PY680+PY 681)
1 PY686 6560-150001-000 VOLUME KNOB ALUMINIUM SKIN AP133601 BLACK (use with PY680+PY681)
2 PY592 6050-150004-002-02 A zur-640A SELECTOR KNOB S ILVER
2 PY593 6050-150004-002-01 A zur-640A SELECTOR KNOB B LACK
3 PY719 6050-150012-000-01 7MM TAC SWITCH BUTTON (BLACK)
3 PY720 6050-150012-000A01 7MM TAC SW ITCH BUTTON (SILVER)
4 6050-150013-000A01 7MM PUSH SWITCH BUTTON SILVER FOR Azur-640A
4 6050-150013-000 7MM PUSH SWITCH BUTTON BLACK FOR Az ur-640A
5 6050-117821-000-02 Azur-640A CONTROL BOX BUTTON SILVER
5 6050-117821-000-01 Azur-640A CONTROL BOX BUTTON BLACK
6 PY541 6050-150010-000A01 PLASTIC FOOT SILVER
6 PY531 6050-150010-000 PLASTIC FOOT BLACK
7 PY544 6600-170100-000 FOOT PAD FOR AZUR RANGE
8 PY1058 3200-076771E000 115/230V 30V*2/3A 17V*2/0.4A Azur-540A V2 AP 175704
9 PY1032 6550-150017-001-02 LARGER S IDE PANEL SILVER P AINTED

9 PY1033 6550-150017-001-01 LARGER S IDE PANEL BLACK PAINTED
10 PY1034 6550-150037-000-02 V2 AMP TOP PANEL SILVE R PAINTED
10 PY1035 6550-150037-000-01 V2 AMP TOP PANEL BL ACK PAINTED
11 PY1036 8554-015010-701 LARGER SUPP ORT FRONT ASSY (WITH TWO B RASS INSERTS)
12 PY1037 8554-015020-701 LARGER SUPP ORT REAR ASSY (WITH TWO BRAS S INSERTS)
13 PY1059 8554-015001-302 Azur-540A V2-Silver AMP FRONT PANEL ASSY
13 PY1060 8554-015011-302 Azur-540A V2-Blac k AM P FRONT PANEL ASS Y
14 PY1040 9464-015002-041 Azur-640A/540A V 2 PIC CONTROL BOARD AS SY REV A
15 PY1041 9464-015002-171 Azur-640A/540A V 2 POWE R SWITCH PCB REV A

PY1042 9464-015002-191 Azur-640A/540A V2 LE D PCB ASS Y REV A
16 PY1061 9454-015002-071 Azur-540A V2 POWER INPUT BOARD AS SY REV A
17 PY1062 9454-015002-091 Azur-540A V2 AMP PO WER PCB ASSY REV A
18 PY1045 9464-015002-001 640A/540A V2 PROTECTION CIRCUITRY PCB-A AS SY REV A
19 PY1046 9464-015002-101 640A/540A V2 PROTECTION CIRCUITRY PCB-B AS SY REV A
20 PY1047 9464-015002-331 Azur-640A/540A A -Bus hub PCB A SSY REV A
21 PY1048 9464-015002-341 Azur-640A/540A V 2 INPUT PCB ASSY REV A
22 PY1049 9464-015002-541 Azur-540A/640A V 2 SPEAK ER CONN. BOARD AS SY REV A
23 PY944 9805-054010-001 AZUR-540A/C,640A/C V2.0 REM OTE CONTROL ASSY REV A

PY945 6040-150002-000-01 BATTERY-DOOR FOR Azur R/C BLACK P AINTED
24 PY1056 6550-150021E001A03 AZUR 540A V2.0 FRONT PANEL-Silver (Metal only)
24 PY1054 6550-150021E001-03 AZUR 540A V2.0 FRONT PANEL-Black (Metal only)
25 PY515 7002-608010-001 Sc rew M2.6 x 8 M /C Torx Recessed 1/K Head Black
25 PY516 7002-608010-006 Sc rew M2.6 x 8 M /C Torx Recessed 1/K Head En-Plated

PY1051 5100-641500E300 AZUR 540A/640A V2 USER'S M ANUAL (AP183031)

13

24

15

10

25

20

22

21

11

4

9

18 (a)

19 (b)

17

5

8

14

1

2

6

3

7

16

12

23

Cambridge Audio Azur 540A V2.0 Amplifier

To enhance viewing, please print to A3 5

CN8

3,96MM 3W ST HEADER

-15V

1
2
3

LK50

LINK15MM

LK86

LINK10MM

LK83

LINK10MM

LK79

LINK10MM

LK75

LINK10MM

LK71

LINK10MM

LK63

LINK10MM

LK67

LINK10MM

C35

100N 100V X7R

C36

100N 100V X7R

C37

100N 100V X7R

-15V

+15V

D1

1N4004

AC Sense

D2

1N4004D31N4004

D4

1N4004D51N4004

LK48

LINK15MM

LK82

LINK10MM

LK78

LINK10MM

LK74

LINK10MM

LK70

LINK10MM

LK64

LINK10MM

LK66

LINK10MM

LK88

LINK10MM

+15V

R55

4k7

Main

Unreg for Relays

Main

-15V

PIC Standby Relay

R56

4k7

C38

1U 25V

C32

1000U 35V EL

C33

1000U 35V EL

LK34

LINK15MM

LK31

LINK10MM

LK29

LINK10MM

LK22

LINK10MM

LK6

LINK15MM

LK13

LINK10MM

LK41

LINK15MM

LK47

LINK10MM

+15V

LK40

LK10MM

C34

47N PE 63V

-15V

+5V

R114

4k7

LK105

LK10MM

Q7

BC327

LK106

LK10MM

C27

100N 50V X7R

1

C31

47N PE 63V

2

LK32

LINK15MM

LK30

LINK10MM

LK28

LINK10MM

LK26

LINK10MM

LK23

LINK10MM

LK7

LINK15MM

LK42

LINK15MM

LK44

LINK10MM

U4

L7815

U2

L7915

1

VI

VI

Standby Relay

U3

VI

GND

2

1

GND

L7805

2

+5V

R114

4k7

R56

4k7

C38

1U 25V

D8

1N4148

Revision󰼿1

LK105

LK10MM

Q7

BC327

LK106

LK10MM

Standby Relay

PIC Standby Relay

3

VO

GND

DGND

3

VO

3

VO

C25

100N 50V X7R

C30

47N PE 63V

C29

47N PE 63V

+5V

C26

47u 16V

C28

100U 25V EL 105

C98

100U 25V EL 105

D9

1N4004

D10

1N4004

+15V

J7

TERMINAL

-15V

LK98

LINK10MM

LK12

LINK15MM

Main Main

LK17

LINK15MM

+15V

GENERAL NOTES

1.

Rev2:󰼿D8󰼿Removed,󰼿LK105󰼿and󰼿106󰼿added.

2.

Rev4:󰼿D9󰼿and󰼿D10󰼿added.

3.

4.

5.

AP17649/5 Input PCB Schematic (Power Supply)

Cambridge Audio Azur 540A V2.0 Amplifier

To enhance viewing, please print to A3 6

R113

47R no stuff

C86

1N 50V NP0 no stuff

C83

100p 50V NP0

R110

47k 1/8W

5

LCh Out

RCh Out

7

6

U18:B

NE5532N

LK68

LK10MM

LK9

LK15MM

LK8

LK15MM

TERMINAL

R109

1k 1/8W

L

J2

C82

10U NP 16V

LK43

LK5

R59

CN16:B

AV2-8,4-9

3

PreOut Left

C48

100p 50V NP0

R79

47k 1/8W

6

5

U17:B

7

NE5532N

LK69

LK10MM

LK57

LK10MM

LK15MM

LCh HP Out

1k8

R58

RCh HP Out

LK15MM

1k8

GENERAL NOTES

Rev1:󰼿Resistors󰼿R72,78,80,82,84,86,88,90,92,94,97,109󰼿changed󰼿to󰼿75R

1.

Rev4:󰼿Resistors󰼿R72,78,80,82,84,86,88,90,92,94,97,109󰼿changed󰼿to󰼿1k

2.

3.

4.

5.

CN15:D

AV4-8,4-9

C47

10U NP 16V

5

6

R61

3k6

U6

3

2

R60

3k6

U6

100p 50V NP0

6

C80

U6

100p 50V NP0

+15V

8 4

CN15:B

AV4-8,4-9

C53

R83

47k 1/8W

5

NE5532N

U9:A

NE5532N

-15V

3

R74

220R 1/8W

6

7

LK73

LK10MM

LK56

LK15MM

U9:B

7

C41

47N 63V PE

1

C42

47N 63V PE

U16:B

NE5532N

CN12:D

AV4-8,4-9

100p 50V NP0

C51

10U NP 16V

R112

100P 50V NP0

R111

6

R76

220R 1/8W

220R 1/8W

C85

U6

220R 1/8W

U6

CN12:B

AV4-8,4-9

C78

C57

100p 50V NP0

R87

47k 1/8W

5

7

U6

U6

3

R78

1k 1/8W

6

U15:B

NE5532N

LK77

LK10MM

LK53

LK15MM

CN13:D

AV4-8,4-9

U6

PreOut Left

U6

PreOut Right

C84

100P 50V NP0

6

R82

1k 1/8W

10U NP 16V

LK49

LK15MM

LK59

LINK15MM

CN13:B

AV4-8,4-9

C55

100p 50V NP0

R91

47k 1/8W

5

3

R86

1k 1/8W

C61

6

7

LK81

LK10MM

LK91

LK15MM

J8

TERMINAL

CN14:D

AV4-8,4-9

U13:B

NE5532N

6

R90

1k 1/8W

10U NP 16V

C59

CN14:B

AV4-8,4-9

C65

100p 50V NP0

R95

47k 1/8W

5

LK85

LK10MM

LK90

LK15MM

3

R94

1k 1/8W

7

LK93

LK10MM

LK94

LK10MM

6

U14:B

NE5532N

LK51

LK15MM

U6

Control󰼿Bus󰼿IR

ABUS󰼿PCB󰼿DGnd

ABUS󰼿PCB󰼿+5V

6

5

7

LK58

LK10MM

LK61

LK10MM

C63

10U NP 16V

-15V

C68

47n 63V PE

100N 50V X7R

10
11
12
13
14

SW GND

ABUS󰼿IR

ABUS󰼿Status

ABUS Control Signals

2,5MM 5W ST HEADER

U10:B

NE5532N

100p 50V NP0

R99

100R

1
2
3
4
5
6
7
8
9

TC9163AF

CN9

47n 63V PE

C66

R96

47k 1/8W

U14:A

NE5532N

LK100

LK15MM

C88

SW GND

Vss

L-S1

L-S2

L-S3

L-COM1

L-S4

L-S5

L-S6

L-COM2

L-S7

L-S8

L-COM3

ST

GND

1
2
3
4
5

-15V

C39

U10:A

NE5532N

3

U6 U6

C64

10U NP 16V

2

3

+15V

84

C67

47n 63V PE

1

+15V

-15V

C89

100N 50V X7R

Vdd

28

R-S1

27

R-S2

26

R-S3

25

R-COM1

24

R-S4

23

R-S5

22

R-S6

21

R-COM2

20

R-S7

19

R-S8

18

R-COM3

17

DATA

16

CLK

15

LK101

LK10MM

Abus GND

Standby Relay

+5VOLTS

C87

1N 50V NP0

2

C40

47n 63V PE

1

Amp Mute

+15V

84

-15V

C69

47n 63V PE

R98

100R

U11

C62

100p 50V NP0

R93

47k 1/8W

U13:A

NE5532N

LK87

LK10MM

LK99

LK15MM

J1

TERMINAL

Aux

1

CN14:A

AV4-8,4-9

2

R97

1k 1/8W

2

3

+15V

84

1

47n 63V PE

LK84

LK10MM

LK89

LK15MM

LK97

CN5

1
2
3
4
5
6
7

2,5MM 7W ST HEADER
To PIC

C60

10U NP 16V

C70

LK10MM

Clock
Data
DGnd󰼿from󰼿PIC
Strobe
Control󰼿Bus󰼿IR
ABUS󰼿IR
Amp󰼿Mute

CD

4

CN14:C

AV4-8,4-9

5

R92

1k 1/8W

C58

100p 50V NP0

R89

47k 1/8W

-15V

C72

47n 63V PE

LK80

LK10MM

LK92

LK10MM

GND󰼿Links󰼿on󰼿underside

1

3

LK55

DAB

CN13:A

AV4-8,4-9

2

R88

1k 1/8W

2

1

U15:A

NE5532N

LK52

LINK15MM

C56

10U NP 16V

LK10MM

+15V

84

C71

47n 63V PE

LK60

LINK15MM

J4

TERMINAL

J5

TERMINAL

J6

TERMINAL

DVD

4

CN13:C

AV4-8,4-9

5

R84

1k 1/8W

C52

10U NP 16V

-15V

C73

47n 63V PE

U6

100p 50V NP0

R85

47k 1/8W

LK76

LK10MM

LK54

LK10MM

1

3

1

U16:A

NE5532N

R100

470k

R101

470k

MD

CN12:A

AV4-8,4-9

2

100p 50V NP0

R80

1k 1/8W

C54

2

LK95

LK10MM

U6

C77

+15V

84

C74

47n 63V PE

R104

LK96

LINK15MM

R103

TO1

4

5

R77

220R 1/8W

C50

100p 50V NP0

R81

47k 1/8W

-15V +15V

C75

47n 63V PE

LK72

LK10MM

LK62

1k8

1k8

CN12:C

AV4-8,4-9

3

U17:A

NE5532N

LK10MM

5

6

3

2

-15V

TO2

1

CN15:A

AV4-8,4-9

2

100p 50V NP0

R75

220R 1/8W

C49

10U NP 16V

2

1

C90

10P 50V NPO

R105

1k8

C93

10P 50V NPO

+15V

8 4

C79

84

C76

47n 63V PE

U12:B

NE5532N

C91

47N PE 63V

C92

TM

4

CN15:C

AV4-8,4-9

5

C81

10U NP 16V

C46

100p 50V NP0

R73

47k 1/8W

-15V

C45

47n 63V PE

2,5MM 3W ST HEADER

R106

560R

7

R102

1k8

U12:A

1

NE5532N

47N PE 63V

U18:A

NE5532N

LK65

LK10MM

3

R

PO

1

CN16:A

AV2-8,4-9

2

U6

PreOut Right

R72

1k 1/8W

2

84

C44

47n 63V PE

1

ABUS Audio Out

CN10

1
2
3

R107

560R

U6

+15V

RCh
GND
LCh

RCh In

LCh In

AP17649/5 Input PCB Schematic (Buffer and Switches)

Cambridge Audio Azur 540A V2.0 Amplifier

To enhance viewing, please print to A3 7

RCh In

LCh In

RL1:A

ME2-5S

LK109

LK15MM

4

5

7

8

1

2

LK104

LK10MM

LK108

LK15MM

RL1:B

ME2-5S

RL1:C

ME2-5S

3

6

LK107

LK10MM

D8

1N4004

LK16

LK10MM

LK18

LK15MM

Q9

MPSA14

R122

10k

R25

1k1

R21

2k2

+5VOLTS

R123

1k

R24

1k1

R19

2k2

VR1:B

B5K LINEAR

VR1:A

B5K LINEAR

VR2:B

B5K LINEAR

VR2:A

B5K LINEAR

C21

680N 63V PE

5

C20

1N5 63V PE

R22

4k7

5

C22

680N 63V PE

Amp Mute

2

C19

1N5 63V PE

R20

4k7

2

46

46

C5

13

R23

1k1

LK21

LK15MM

LK19

LK15MM

R17

2k2

13

U2

R26

1k1

LK20

LK15MM

R18

2k2

3

U4

2

+15V

3

2

8 4

-15V

+15V

-15V

C14

47N 63V PE

8 4

C9

47N 63V PE

C10

47N 63V PE

C18

10P 50V NPO

U6:A

NE5532N

1

C16

47N 63V PE

C23

10P 50V NPO

U5:A

1

NE5532N

U2

R36

2k2

U2

U4U4

R37

2k2

47U NP 16V

C6

10N PP 63V

U6:B

6

7

5

NE5532N

R35

U2

2k2

C13

10P 50V NPO

C4

47U NP 16V

C3

10N PP 63V

C24

U5:B

6

7

5

NE5532N

C7

47U NP 16V

R38

U4

2k2

C8

10P 50V NPO

C12

10N PP 63V

C11

47U NP 16V

R14

150k

10N PP 63V

R15

150k

SW2:B

SW-DPDT
Tone Defeat

R16

150k

R13

150k

SW2:A

SW-DPDT
Tone Defeat

LK27

LK10MM

VR4:B

MN20K BALANCE

5

4 6

Out

LK37

LK15MM

VR4:A

13

MN20K BALANCE

out

5

VR3:B

4 6

20K MOTORISED DUAL POT

2

2

VR3:A

1 3

20K MOTORISED DUAL POT

LK35

LINK15MM

LK36

LINK15MM

C105

10N PP 63V

C104

10U NP 16V

R31

22k

C100

10N PP 63V

C101

10U NP 16V

R29

22k

+15V

C15

-15V

100U 25V EL

C17

100U 25V EL

RCh Out

LK25

LK24

LK10MM

LK10MM

U4

U7:B

5

6

NE5532N

U2

R33

7

22R

R32

1k5

C106

R30

10P 50V NPO

3k

Out

Out

+15V

RCh Out

J3

LK33

LK15MM

TERMINAL

Out

LCh Out

CN3

1
2
3
4
5
6

H6 2.54mm
TO POWER AMP

CN17

2
1

2MM 2W ST HEADER

C102

47N 63V PE

84

U7:A

NE5532N

2

3

C99

R27

10P 50V NPO

1k5

R28

3k

Out

C103

47N 63V PE

-15V

Out

OutOut

R34

1

22R

LCh Out

MAIN

GENERAL NOTES

Rev2:󰼿RL1,D8,Q9,R122,R123,LK104,107-109󰼿added.

1.

2.

3.

4.

5.

AP17649/5 Input PCB Schematic (Tone Control)

Speaker Test

To enhance viewing, please print to A3 8

+5V

Cambridge Audio Azur 540A V2.0 Amplifier

Speaker󰼿Cable󰼿Short󰼿Circuit󰼿Detector

Speaker short circuit tester

LK14

LK10MM

LK103

LK10MM

D6

1N4004

Senses a DC resistance of 2 ohms or less

R66

1k
For 1mA

R67

100R

R64

10k

R65

2R7

3

2

84

R62

no stuff

U8:A

LM393

+5Volts

C43

100N 50V X7R

1

R69

4k7
(Open Collector Output)

D7

PIC VI/Short

1N4148

LK102

Speaker󰼿PCB󰼿Control

SPEAKER B SWITCHING (for relay)

SW1:B

LK10

SW-DPDT
TAPE

LK11

LINK15MM

LINK15MM

Unreg for Relays

LK10MM

Speaker Test

Speaker A Relay

LK46

R57

220R 2W Carbon

LK45

CN11

1
2
3
4
5
6

2,5MM 6W ST HEADER

To Speaker PCB CN1

LK15

LK10MM

+5V

Mains󰼿PCB󰼿Control

CN7

3
2
1

2,5MM 3W ST HEADER

PIC Standby Relay

R108

220R 2W Carbon

Unreg for Relays

DGND

Temp Sense

+5Volts

R71

R70

4k7

10k

5

6

R63

910R

910 / (910 + 10k) with ZP221A501E
voltage gives 100deg C cutout

U8:B

LM393

R68

100k

DGND

1
2
3
4
5
6
7
8

C107

100U 16V EL

CN6

To PIC

+5V

DGND

R115

CN4

1

7

PIC Temp

2,5MM 5W ST HEADER

LK38

2
3
4
5

PIC VI/Short

PIC CLIP

DGND

Temp Sense

R116

10k

DGND

GENERAL NOTES

Rev3:󰼿R65󰼿Changed󰼿from󰼿10R󰼿to󰼿8R2

1.

2.

Rev4:󰼿R65󰼿Changed󰼿from󰼿8R2󰼿to󰼿4R7

3.

Rev5:󰼿R65󰼿Changed󰼿from󰼿4R7󰼿to󰼿2R7

10k

Q8

BC337

PIC󰼿Protection󰼿signals

PIC DC

+5V

DGND

PIC Temp

PIC VI/Short

PIC Standby Relay

PIC DC

PIC CLIP

Speaker A Relay

C108

100N 50V X7R

R117

4k7

Open Collector Output

LK39
LK10MM

2,5MM 8W ST HEADER

4.

5.

AP17649/5 Input PCB Schematic (Protection Circuitry)

Cambridge Audio Azur 540A V2.0 Amplifier

To enhance viewing, please print to A3 9

R39

5k6

Q6

R118

1k5

BD139

RCh HP Out

(Rch󰼿Out)

LCh HP Out

(Lch󰼿Out)

R52

100R

R49

100R

Main

Main

R51

No Stuff

R50

No Stuff

-15V

+15V

R53

10R

Main

Main

R54

10R

R119

3k

R120

1k5

R121

3k

5

6

2

3

U1:B

NE5532N

LK4

LINK10MM

470U 25V EL

C96

47N 63V PE

84

U1:A

NE5532N

C95

47N 63V PE

C94

470U 25V EL

Main

C97

1

Q4

BD140

Q3

BD139

R3

1R

R1

1R

Q1

BD140

R8

1R

R6

1R

Main

Main

R9

180R

C2

10N 63V PE

R4

180R

C1

10N 63V PE

R10

360R

R5

360R

CN2

1
2

2,5MM 2W ST HEADER

R11

10R 2W

R12

10R 2W

Main

CN1

8

7

3

2

1

HEADPHONE JACK

RSW1

RSW2

R

L

GND

R43

7

560R

R42

560R

BD139

Q5

R40

3k3

R41

2k7

R7

5k6

R44

5k6

Main

R48

560R

R47

560R

LK3

LINK10MM

LK1

LINK10MM

LK2

LINK10MM

BD139

Q2

R45

3k3

R46

2k7

R2

5k6

GENERAL NOTES

1.

Rev1:󰼿Resistors󰼿R118-121󰼿added
Rev2:󰼿Resistors󰼿R11,R12,R118-121󰼿values󰼿changed.

2.

3.

4.

5.

AP17649/5 Input PCB Schematic (Headphone Driver)

Cambridge Audio Azur 540A V2.0 Amplifier

To enhance viewing, please print to A3 10

Super Hi-Fidelity Ultra Linear P reamp Stage

AP17649/4 Input PCB Board Layout (Top Side)

Cambridge Audio Azur 540A V2.0 Amplifier

To enhance viewing, please print to A3 11

AP17649/4 Input PCB Board Layout (Bottom Side)

A

y)

K

)

)

)

)

K

)

)

K

)

)

y

y

Cambridge Audio Azur 540A V2.0 Amplifier Input PCB Assembly BOM

12

P Part

No

Value Description/Type Factory Part No. Qty Component Ident Notes

RESISTORS

1R 0.25W metal film 4 R1, 3, 6, 8.

2R7 0.25W metal film 1 R65

10R 0.25W metal film 2 R53, 54
22R 0.25W metal film 2 R33, 34
100R 0.25W metal film 5 R49, 52, 67, 98, 99.
180R 0.25W metal film 2 R4, 9
360R 0.25W metal film 2 R5, 10
560R 0.25W metal film 6 R42, 43, 47, 48,106,107
910R 0.25W metal film 1 R63
1
1K1 0.25W metal film 4 R23-26

1K5 0.25W metal film 4 R27, 32, (118,120)

1K8 0.25W metal film 6 R58, 59, 102-105.
2K2 0.25W metal film 8 R17-19, 21, 35-38
2K7 0.25W metal film 2 R41, 46

3K 0.25W metal film 4 R28, 30, R119, (R121)

3K3 0.25W metal film 2 R40, 45
3K6 0.25W metal film 2 R60, 61
4K7 0.25W metal film 8 R20, 22, 55, 56, 69, 71, 114, 117
5K6 0.25W metal film 4 R2, 7, 39, 44
10
22
100K 0.25W metal film 1 R68
150K 0.25W metal film 4 R13-16
470K 0.25W metal film 2 R100, 101

1k 0.125W metal film 12

220R 0.125W metal film 6 R74-77, 111, 112.

47K 0.125W metal film 12

10R 2W Carbon 2 R11,12

220R 2W Carbon 2 R57, 108

0.25W metal film 2 R66,(R123

0.25W metal film 5 R64, 70, 115, 116,(122

0.25W metal film 2 R29, 31

R72, 78, 80, 82, 84, 86, 88, 90, 92, 94,
97, 109.

R73, 79, 81, 83, 85, 87, 89, 91, 93, 95,
96, 110,

CAPACITORS

10pF 50V NP0 Ceramic 1181-100042-000 8 C8, 13, 18, 23, 90, 93, 99, 106.

100pF 50V NP0 Ceramic 1181-101042-000 18

1nF 50V Ceramic 1100-102043-000 1 C87
100nF 50V Ceramic 1100-104043-000 6 C25, 27, 43, 88, 89, 108
100nF 100V Monolythic Ceramic 1106-104064-001 3 C35, 36, 37.

1.5nF 63V Polyester film 2 C19, 20
10nF 63V Polyester film 1117-103052-000 2 C1, 2

47nF 63V Polyester film 1117-473053-000 30

680nF 63V Pol
10nF 63V Polypropylene film 6 C3, 6, 12, 24, 100, 105

10uF 16V

47uF 16V

1uF 25V Polarised Electrolytic 1102-107024-000 1 C38
47uF 16V Polarised Electrolytic 1102-470014-000 1 C26
100uF 16V Polarised Electrolytic 1102-101014-000 1 C107.
100uF 25V Polarised Electrolytic 1102-101024-000 2 C15, 17

ester film 2 C21, 22

Non Polarised
Electrol
Non Polarised
Electrolytic

tic

1105-100013-000 14

C46, 48, 50, 53, 54, 57, 58, 61, 62, 65,
66, 77-80, 83, 84, 85

C9, 10, 14, 16,29-31, 34, 39, 40, 41,
42, 44, 45, 67-76, 91,92,95, 96, 102,
103

C47, 49, 51, 52, 55, 56, 59, 60, 63, 64,
81, 82, 101, 104

4 C4, 5, 7, 11,

AP17652/5

See Input Schematic (Protection
Circuitr

See Input Schematic (Tone Control

See Input Schematic (Headphone
Driver

See Input Schematic (Headphone
Driver

See Input Schematic (Tone Control

See Input Schematic (Buffers and
Switches

See Input Schematic (Headphone
Driver

Note: resistors, capacitors and other 'generic' electronics components are not usually stocked by

the manufacturer. Please obtain these locally.

A

Cambridge Audio Azur 540A V2.0 Amplifier Input PCB Assembly BOM

p

p

)

)

k

(

)

y

)

13

P Part

No

PY219 BC327-25 PNP Signal 1301-327000-100 1 Q7
PY214 BC337-25 NPN Signal 1300-337000-100 1 Q8

PY319 1N4004 Rectifier 1401-140040-000 9 D1-6,(D8, D9, D10)

PY759 1N4148 Signal 1401-141480-000 1 D7

PY108 NE5532N 4155-320052-900 13 U1, 5-7, 9, 10, 12-18

PY539 LM393 4139-300052-600 1 U8
PY476 TC9163AF 4191-630103-000 1 U11

PY1013 20kA

PY045 2P2T Push Switch 2402-020200-010 2 SW1, 2

PY584 5V Rela

Value Description/Type Factory Part No. Qty Component Ident Notes

100uF 25V

470uF 25V Polarised Electrolytic 2 C94, 97
1000uF 35V Polarised Electrolytic 1102-102034-000 2 C32, 33

105 degree Polarised
Electrolytic

2 C28, 98.

TRANSISTORS

BD140 PNP Low power 2 Q1, 4

BD139 NPN Low power 4 Q2, 3, 5, 6,

NPN Darlington 1300-140000-100 1 Q9 See Input Schematic (Tone Control

DIODES

INTEGRATED CIRCUITS

L7915CV 1 U2
L7805 1 U3
L7815CV 1 U4

POTS

Motorised Dual Volume

Pot
MN20
5kB Dual Linear Pot 1062-002518E130 2VR1, 2 High Torque

Dual Balance Pot 1062-003518E160 1VR4 High Torque

1062-003511E110 1 VR3 High Torque

SWITCH

MISCELLANEOUS

LK1-4, 13, 22, 23, 26, 28-31, 44, 47,
63, 64, 66, 67, 70, 71, 74, 75, 78, 79,
82, 83, 86, 88, 98, 14-16,24, 25, 27,

70

38-40, 45, 46, 54, 55, 57, 58, 61, 62,
65, 68, 69, 72, 73, 76, 77, 80, 81, 84,
85, 87, 92-95, 97, 101­103,(104,105,106,107)

LK5, 8, 9, 18-21, 33, 37, 43, 49, 51,
53, 56, 89-91, 99, 100, 6, 7, 10-12, 17,

39

32, 34-36, 41, 42, 48, 50, 52, 59, 60,

108,109

96,

LINK10mm

LINK15mm

24SWG Tinned Copper

Wire

24SWG Tinned Copper

Wire

4050-000005-002 1 RL1 See Input Schematic (Tone Control

AP17652/5

Q1 and Q2 must be thermally coupled
and Q4 and Q5 must be thermally
coupled, please see misc section for

arts
Q1 and Q2 must be thermally coupled
and Q4 and Q5 must be thermally
coupled, please see misc section for

arts

See Input Schematic (Power Supply &
Tone Control

See Input Schematic (Power Supply &
Tone Control)

See Input Schematic (Tone Control)

Note: resistors, capacitors and other 'generic' electronics components are not usually stocked by

the manufacturer. Please obtain these locally.