Cambridge Audio azur 840A User manual

Gallery Court Hankey Place London SE1 4BB UK
Tel: [phone] Fax: [phone]
840A
Issue Date: 16th June 2006
________________________________________________________________________________
SERVICE MANUAL
________________________________________________________________________________
SPECIFICATIONS:
Power Output 120W RMS into 8 Ohms
200W RMS into 4 Ohms
THD (unweighted) < 0.0015% 1 kHz
at 80% of rated power
< 0.015% 20Hz – 20kHz
at 80% of rated power
Frequency Response 10Hz – 50kHz +/- 1dB
S/N ratio (ref 1W/8 Ohm) >83dB
Input Impedances Input 1 (balanced) 10 kOhm
Inputs 2-7 68 kOhm
Tape Input 68 kOhm
Power Amp damping factor > 110 at 1kHz
Max power consumption 800W
Minimum power consumption Active (no signal) 70W
Standby 7W
Bass & Treble controls Shelving type
Max bass boost/cut +/- 10dB at 10Hz
Max treble boost/cut +/- 7.5dB at 20Hz
Dimensions (H x W x D) 115 x 430 x 385mm
(4.5 x 16.9 x 15.2”)
Weight 15.0kg (33Lbs)
AP19597/1
1

840A SERVICE MANUAL
TABLE OF CONTENTS
Safety Precautions & Important Notes 4
Block Diagram 5
Exploded Diagram 6
Exploded Diagram Parts List 7
Front Panel PCB Schematic (Microcontroller & LCD) 8
Front Panel PCB Schematic (Shift Registers) 9
Front Panel PCB Layout (Top Side) 10
Front Panel PCB Layout (Bottom Side) 11
Front Panel PCB BOM 12
Input PCB Schematic (Input Select) 13
Input PCB Schematic (Input Control) 14
Input PCB Schematic (Input Amplifier) 15
Input PCB Board Layout (Top Side) 16
Input PCB Board Layout (Bottom Side) 17
Input PCB BOM 18
Preamp PCB Schematic (Relay Logic) 19
Preamp PCB Schematic (Tone Control) 20
Preamp PCB Schematic (Post Amp) 21
Preamp PCB Board Layout (Top Side) 22
Preamp PCB Board Layout (Bottom Side) 23
Preamp PCB BOM 24-25
Power Amplifier Schematic (Right Power Supplies & PSU) 26
Power Amplifier Schematic (Right Channel) 27
Power Amp Right & PSU PCB Board Layout (Top Side) 28
Power Amp Right & PSU PCB Board Layout (Bottom Side) 29
Power Amp Right PCB BOM 30-31
Power Amp PSU PCB BOM 32
Power Amp Schematic (Left Channel) 33
Power Amp Schematic (Left Power Supplies) 34
Power Amp PCB Board Layout (Top Side) 35
Power Amp PCB Board Layout (Bottom Side) 36
Power Amp Left PCB BOM 37-38
Hub PCB Schematic 39
2

Hub PCB Board Layout (Top Side) 40
Hub PCB Board Layout (Bottom Side) 41
Hub PCB BOM 42-43
Rectifier PCB Schematic 44
Rectifier PCB Board Layout (Top Side) 45
Rectifier PCB Board Layout (Bottom Side) 46
Rectifier PCB BOM 47
IC Pin Layout Details 48-49
Technical Description 51-60
Procedure to upgrade the Control (Pic) Software 61-62
Notes 63
3

SAFETY PRECAUTIONS & IMPORTANT NOTES
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.
© 2007Audio 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.
4

Cambridge Audio Azur 840A Amplifier
840A Block Diagram
To enhance viewing, please print to A3 5

7
10
62
3
9
17
418
15
8
13
5
11
16
6
1
15
14
12
5
Cambridge Audio Azur 840A Amplifier
840A Exploded Diagram
To enhance viewing, please print to A3 6

Cambridge Audio Azur 840A Amplifier
Exploded Diagram Parts List
Drawing
Ref:
AP Part
Number noitpircseD:feRyrotcaF
1 PY1118 2331-004909E301 Speaker Binding Post BP331 (Black) Red & Black 2 PY1019 3200-053044E00
0
Toroid 230V/50Hz 36.5VACx4 5.5A TI-053044
C
2 PY1020 3200-053045E00
0
Toroid 115V/50Hz 36.5VAC 5.5A TI-0853045C for 840A
3 PY1119 3200-074051E001 Toroid 230V/50Hz 7.5VAC750MA 17VAC*2 TO7405B ST
B
3 PY1120 3200-077811E00
0
Toroid 115V/50Hz 7.5VAC750MA 17VAC*2 ST
B
4 PY1121 6074-150003E000-01 840A Bass / Treble Knob (Black) Painted Blac
k
4 PY1123 6074-150003E001A01 840A Bass / Treble Knob (Silver) Painted Silve
r
5 PY1122 6074-150004E00
0
A
zur 840A Plastic Foot (Black) AP16837
*
5 PY1124 6074-150004E000A01
A
zur 840A Plasitc Foot (Silver) AP16837
*
PY1125 6574-150009E000-01
A
zur 840A Top Panel Black Painted
PY1126 6574-150009E000-0
2
A
zur 840A Top Panel Silve
r
6 PY112
7
6574-150013E000-01
A
zur 840A Side Panel, Black Painted
6 PY1128 6574-150013E000A01
A
zur 840A Side Panel,Silve
r
7 PY1129 8584-015010E301
A
zur 840A Black Front Panel Ass
y
7 PY1130
A
zur-840A Silver Front Panel Ass
y
8 PY1131 6574-150012E000-01
A
zur 840-A B Front Panel Artwork AP186371/186381 (Metalwork Only
)
8 PY1132
A
zur 840-A Silver Front Panel Artwork AP186371/186381 (Metalwork Only
)
PY1133 6074-150005E00
0
A
zur 840A Volume Knob Plastic Insert (AP1743*)
6574-150015E00
0
A
zur 840A Volume Knob Skin, Black
A
zur 840A Volume Knob Skin, Silver
PY1135 3110-840000E00
0
LCD Display Highly Transflective DC00003E02 840
A
PY1136 6600-990112E00
0
A
zur 840A Display Backlight (AP16841*)
PY1138 2409-010200E001 Rotary Encoder Switch REBG161(9*7)PVB20FHINB1-2-24
E
9 PY1139 9484-015000E041
A
zur-840A AMP-Hub Control PCB Assy Rev
A
10 PY1159 9484-015000E341
A
zur-840A Amp Input PCB Assy Rev
A
11 PY1153 9484-015000E141
A
zur-840A EU/UK PSU Power Control PCB Assy Rev
A
12 PY1146 9484-015000E091
A
zur-840A Main-Amp Left PCB Assy Rev
A
13 PY1163 9484-015001E091
A
zur-840A Main-Amp Right PCB Assy Rev
A
14 PY1155 9484-015000E331
A
zur-840A Pre-Amp Board Rev
A
15 PY1145 9484-015000E071
A
zur-840A Amp-Rectifier PCB Rev
A
16 PY113
7
9484-015000E111
A
zur-840A Amp Front Control PCB Assy Rev
A
1
7
PY1134 9484-015000E061
A
zur-840A LCD Display Board Assy Rev
A
18 PY1165 9805-084000E001
A
zur-840A Remote Control Assy Rev
A
All spare parts should be ordered from AP Hong Kong office
7

Cambridge Audio Azur 840A Amplifier
AP16369/3 Front Panel PCB Schematic (Microcontroller & LCD)
MCLR/VPP
1
RA0/AN0
2
RA1/AN1
3
RA2/AN2
4
RA3/AN3/VREF
5
RA4/T0CKI
6
RA5/AN4/SS
7
RE0/RD/AN5
8
RE1/WR/AN6
9
RB4
37
RB3/PGM
36
RB2
35
RB0/INT
33
VDD
32
VSS
31
RD7/PSP7
30
RD6/PSP6
29
RB1
34
RD5/PSP5
28
RD4/PSP4
27
RC7/RX/DT
26
RC5/SDO
24
RC4/SDI/SDA
23
RD3/PSP3
22
RD2/PSP2
21
RC6/TX/CK
25
VDD
11
VSS
12
OSC1/CLKIN
13
OSC2/CLKOUT
14
RCO/T1OSO/T1CKI
15
RC1/T1OSI/CCP2
16
RC2/CCP1
17
RC3/SCK/SCL
18
RD0/PSP0
19
RE2/CS/AN7
10
RD1/PSP1
20
RB5
38
RB6/PGC
39
RB7/PGD
40
U1
PIC16F877A
SW1
SW-TACT
SW2
SW-TACT
SW3
SW-TACT
SW5
SW-TACT
SW6
SW-TACT
SW7
SW-TACT
SW8
SW-TACT
SW4
SW-TACT
SW9
SW-TACT
SW10
SW-TACT
SW11
SW-TACT
INPUT 1 INPUT 2 INPUT 3 INPUT 4
INPUT 5 INPUT 6 INPUT 7 TAPE MON
MODE spare
+5V
LOGIC GND
LCD DISPLAY CONN
C10
100n CER
C11 100n CER
LOGIC GND
SERIAL DATA
SERIAL CLOCK
SERIAL STROBE
SERIAL CONTROL OUT
SERIAL IN FROM A-BUS HUB BOARD
OVERLOAD
HUB DATA
CLIP DETECT
MAINS FAIL
DC OFFSET
PHONES DETECT
PORT B HAS WEAK PULLUPS
RB4-RB7 HAS INTRPT ON CHANGE
R1
22R
R2
43R
Q2
BC337
LOGIC GND
R4
4K7
C1
100n
C2
100nF
ON/STBY SPEAKER SELECT
LOGIC GND
ROW 3
ROW 2
ROW 1
COL 1 COL 2 COL 3 COL 4
X1
CRYSTAL
FREQ=20MHz
C5
22pF
C6
22pF
LOGIC GND
+5V
LOGIC GND
CONNECTOR TO PREAMP PCB
SERIAL IN FROM A-BUS HUB BOARD
Vss 1
Vdd 2
Vo 3
RS 4
R/W 5
E 6
D0 7
D1 8
D2 9
D3 10
D4 11
D5 12
D6 13
D7 14
LED A 15
LED K 16
LOGIC GND
TX
RX
RS232 & IR CABLE TO HUB PCB
IR IN (FROM RECEIVER ON PREAMP BOARD)
C GND
3
ASW
1
BSW
2
FIX2
5
FIX1
4
ROT1
NOBLE16ENCODER
POSITION FOR
EXTRA SWITCH
AK
D2
BLUE LED
ON/STBY LED
IR IN (FROM JACK & PHONO ON HUB PCB)
+15V
IR GND
IR IN
RS232 GND
R10
10R
C9
100N CERAMIC
SERIAL RX 232
C4
10U 16V
C3
10U 16V
R5
100R C20
100nF
LOGIC GND
C21
100n
LOGIC GND
LOGIC GND
Q4
BC337
+15V
RS232 TX
R13
22K
R12
2K2
LOGIC GND
SERIAL TX 232
Q3
BC337
+5V
D3
1N4002
RS232 RX
R11
10K
R9
22K
LOGIC GND
SERIAL RX 232
RS232 RX
RS232 TX
SERIAL TX 232
PROGRAM_CLOCK
PROGRAM_DATA
PGM
MCLR HUB
R14
10K
+5V
+5V
Programming Signals
To ABUS Hub PIC
RS232 TX
RS232 RX
MCLR HUB
PGM
PROGRAM_DATA
PROGRAM_CLOCK
HUB CLOCK
HUB CLOCK
HUB DATA
R3
2K2
OVER TEMP
OVER TEMP
1
2
3
4
5
6
7
8
9
10
12
13
11
CN3
FFC 13WAY
BLOCK
PIC TX
SHIFT REG ENABLE
D
2
CLK
3
STB
1
OE
15
Q0
4
Q1
5
Q2
6
Q3
7
Q4
14
Q5
13
Q6
12
Q7
11
QS
9
QS
10
U2
74HC4094
VDD=+5V
VSS=LOGIC GND
SHIFT REG ENABLE
SERIAL DATA
SERIAL CLOCK
BLOCK
PIC TX
IR CONTROL
PHONES DETECT
OVERLOAD
DC OFFSET
MAINS FAIL
LCD DECOUPLE
C7
100nF
LOGIC GND
+5V
SHIFT REG DECOUPLE
1
2
3
4
5
6
7
8
9
10
11
12
CN1
FFC 12WAY
12
15 16
1
2
3
4
5
6
1a
2a
3a
4a
5a
6a
7
8
7a
8a
CN2
CONN-8 DUAL BOT
RS
E
LCD DATA SHIFT REGISTER
2
1
16
15
LCD CONN ORIENTATION FROM FRONT
C15
100pF
C16
100pF
C17
100n
C18
100n
C19
100n
CLIP DETECT
PIC INPUT EMC CAPS
LED BACKLIGHT POWER
R6
1K1
R7
2K2
R8
1K1
SPEAKER TEST
SPEAKER TEST
C22
100n
+5V
TRISTATE LED CONTROL
0=BRIGHT
TRISTATE= OFF
1= DIM
R15
10K
LOGIC GND
R16
47R
C23
100N CERAMIC
LOGIC GND
FRONT PANEL GROUNDING
Q5
BC337
R17
10K
R18
2K2
C24
10U 16V
Q6
BC337
R19
10K
LOGIC GND
FRONT PANEL GND
FRONT PANEL GND
P2
PAD
P3
PAD
Q1
BC327-25
2
CW
3
CCW
1
PR1
PRESET 20K 3296W
CW
Q8
BC327-25
R23 10R
R24 10R
D4
1N4148
D5
1N4148
D6
1N4148
D7
1N4148
D8
BZX79C2V7 500MW
To enhance viewing, please print to A3 8

Cambridge Audio Azur 840A Amplifier
AP16369/3 Front Panel PCB Schematic (Shift Registers)
D
2
CLK
3
STB
1
OE
15
Q0
4
Q1
5
Q2
6
Q3
7
Q4
14
Q5
13
Q6
12
Q7
11
QS
9
QS
10
U3
74HC4094
VDD=+5V
VSS=LOGIC GND
LOGIC GND
D
2
CLK
3
STB
1
OE
15
Q0
4
Q1
5
Q2
6
Q3
7
Q4
14
Q5
13
Q6
12
Q7
11
QS
9
QS
10
U4
74HC4094
VDD=+5V
VSS=LOGIC GND
D
2
CLK
3
STB
1
OE
15
Q0
4
Q1
5
Q2
6
Q3
7
Q4
14
Q5
13
Q6
12
Q7
11
QS
9
QS
10
U5
74HC4094
VDD=+5V
VSS=LOGIC GND
FROM SHEET 1 SERIAL CLOCK
SERIAL DATA
SERIAL STROBE
SHIFT REG ENABLE
1
2
3
4
5
6
7
8
CN4
FFC 08WAY
1
2
3
4
5
6
7
8
CN5
FFC 08WAY
1
2
3
4
5
6
7
8
CN6
FFC 08WAY
D
2
CLK
3
STB
1
OE
15
Q0
4
Q1
5
Q2
6
Q3
7
Q4
14
Q5
13
Q6
12
Q7
11
QS
9
QS
10
U6
74HC4094
VDD=+5V
VSS=LOGIC GND
1
2
3
4
5
6
7
8
CN7
FFC 08WAY
C8
100nF
+5V
C12
100nF
C13
100nF
C14
100nF
SHIFT REG DECOUPLE
TO PREAMP BOARD
TO PREAMP BOARD
TO PREAMP BOARD
TO INPUT BOARD
To enhance viewing, please print to A3 9

Cambridge Audio Azur 840A Amplifier
AP16369/3 Front Panel PCB Layout (Top Side)
AP16370/3
(c) COPYRIGHT Audio Partnership PLC 2005
U1
ROT1
SW1
SW2
SW3
SW4
SW5
SW6
SW7
SW8
X1
SW9
SW10 SW11
C1
C2
C3
C4
C5
C6
C10
C11
C12
C13
C14
C15
C17
R1
R2
R3
R4
R6
D2
D3
R9
R10
R11
R12
R13
R14
R15
C7
C8
C9
C16
C18
C19
Q1
Q2
Q3 Q4 R5
C20
AP16370/3
C21
C22
R7
U2
U3
U4
U5U6
C24
Q5
R17
R18
R19
Q6
C23
P2
P3
R16
CN2
R23
R24
Q8
R8
D4
D5 D6
D7
D8
To enhance viewing, please print to A3 10