Page 1
Service Manual
FMJ A32, P35 & P35/3
Amplifi ers
A32
Issue 1.0
ARCAM
Page 2
Contents List
!
Phono board L870
o Circuit description
o Component overlay
o Parts list
o Circuit diagrams
!
Amplifier & PSU board L882
o Circuit description
o Component overlay
o Parts list
o Circuit diagrams
!
Display board L928
o Component overlay
o Parts list
o Circuit diagrams
!
Preamplifier board L937
o Circuit description
o Component overlay
o Parts list
o Circuit diagrams
!
3rd Channel Amplifier board L911
o Component overlay
o Parts list
o Circuit diagrams
!
Transformer specifications
o L914TX
o L915TX
!
General assembly
o A32 - Mechanical parts list
o P35 - Mechanical parts list
o P35/3 - Mechanical parts list
Page 3
Phono
Board
L870
Contents
!
Circuit description
!
Component overlay
!
Parts list
!
Circuit diagrams
Page 4
AV8 Phono Board
Circuit Description
Refer to circuit diagram L870 sheet 1
The phono board is a simple single stage RIAA amplifier
and consists of two channels of high gain amplification,
and the ability to switch between moving magnet (MM)
and moving coil (M C) settings.
PSU
The unit derives its +
fitted into with only local decouplin g capacitors on board.
Interface
The unit connects to the host unit via a 8 way connector.
Amplification
The left channel h as designators beginnin g with 100, and
the right with 200. For the purposes of this description the
left channel will be described, as the right channel is the
same in all respects.
The amplifier is a small signal class A voltage feedback
amplifier with switch able gain. The input consists of an
actively loaded differential pair of very low noise PNP
transistors (TR106, TR107). These transistors are very
specific and should only be replaced with identical parts
with the E grade high gain. TR100 and TR101 form a
current source for the pair, which sets the qu iescent current
for the entire amplifier. The active load consists of TR110
and TR111, which forms part of the differential current
mirror with TR112, TR113 & TR114. This differential
stage also h as an active load (TR102 & TR10 3) to keep
gain to a maximum.
Both of these di fferential stages are design ed to have as
much gain as p ossible to enable the single stage desi gn .
The RIAA respon se is achieved in th e feedback network:
C101, C110, C111, C112, C119, C120 and R115, R112.
C115 is used to correct between MM and MC gains as the
amplifier is non-inverting.
SW100 switches between MM and MC. Two poles of the
switch change between the different loading required for
each type of the cartridge: R108 & C109 for MM and
added in parallel for MC R104 & C108. The other two
poles chan ge the feedbac k resister valu e to alter th e gain:
R105 for MM and added in parallel for MC R123.
The DC offset is c ontrolled by a non-i nverting s ervo built
around IC100. The amount of servo current is different for
each gain setting via R111 (MM) and R124 (MC) so that
the low frequency high pass point remains the same for
both settings. However the high pass point for the circuit
is set by C113. This gives a warp filter, stops DC start-up
thumps from upsetting DC coupled circuitry and an
approximation of the RIAA/IEC curve (-2d B @ 20Hz)
The output is class A buffered by a d ual mirror follower
(TR104, TR105, TR108, TR109). The quiescent current is
set by D100 and R118 and R119.
Closed loop st ability is achieved with C16, C117, gi ving
symmetrical slewing capability.
15V regulated rails from the unit it is
Page 5
Page 6
L870 Phono Board Parts List Issue 2.0
Designator Part Description
C1 2A410 CERD 100N 63V -20% +80% RA
C100 2N622 ELST 22U 63V
C101 2D210 PPRO 1N0 5% 63V RA
C102 2P710AS ELEC 100U 25V SILMIC
C103 2P710AS ELEC 100U 25V SILMIC
C104 2K410 PEST 100N 63V 10%
C105 2K410 PEST 100N 63V 10%
C106 2K410 PEST 100N 63V 10%
C107 2K410 PEST 100N 63V 10%
C108 2D147W PPRO W 470P 63V 5% RA
C109 2D110W PPRO W 100P 63V 5% RA
C110 2D247N PPRO 4N7 63V 5% RA
C111 2D310 PPRO 10N 63V 1% AXIAL
C112 2D310 PPRO 10N 63V 1% AXIAL
C113 2K510 CAP MKS2 1U0 16V 10%
C115 2D213N PPRO 1N3 63V 5% RA
C116 2D147W PPRO W 470P 63V 5% RA
C117 2D147W PPRO W 470P 63V 5% RA
C118 2U610 ELST NON POLAR 10UF 35V
C119 2D110N PPRO 100P 63V 5% RA
C120 2D210 PPRO 1N0 5% 63V RA
C200 2N622 ELST 22U 63V
C201 2D210 PPRO 1N0 5% 63V RA
C202 2P710AS ELEC 100U 25V SILMIC
C203 2P710AS ELEC 100U 25V SILMIC
C204 2K410 PEST 100N 63V 10%
C205 2K410 PEST 100N 63V 10%
C206 2K410 PEST 100N 63V 10%
C207 2K410 PEST 100N 63V 10%
C208 2D147W PPRO W 470P 63V 5% RA
C209 2D110W PPRO W 100P 63V 5% RA
C210 2D247N PPRO 4N7 63V 5% RA
C211 2D310 PPRO 10N 63V 1% AXIAL
C212 2D310 PPRO 10N 63V 1% AXIAL
C213 2K510 CAP MKS2 1U0 16V 10%
C215 2D213N PPRO 1N3 63V 5% RA
C216 2D147W PPRO W 470P 63V 5% RA
C217 2D147W PPRO W 470P 63V 5% RA
C218 2U610 ELST NON POLAR 10UF 35V
C219 2D110N PPRO 100P 63V 5% RA
C220 2D210 PPRO 1N0 5% 63V RA
D100 3A4148 SSDIODE 1N4148 75V
D101 3A4148 SSDIODE 1N4148 75V
D102 3A4148 SSDIODE 1N4148 75V
D200 3A4148 SSDIODE 1N4148 75V
D201 3A4148 SSDIODE 1N4148 75V
D202 3A4148 SSDIODE 1N4148 75V
IC100 5B071 IC FET OPAMP TL071
IC200 5B071 IC FET OPAMP TL071
PCB1 L870PB_2 PRINTED CIRCUIT BOARD
R100 1H133 RES MF W4 1% 330R
R101 1H110 RES MF W4 1% 100R
R102 1H110 RES MF W4 1% 100R
R104 1H110 RES MF W4 1% 100R
R105 1H110 RES MF W4 1% 100R
R106 1H110 RES MF W4 1% 100R
R108 1H347 RES MF W4 1% 47K
R109 1H312 RES MF W4 1% 12K
R110 1H312 RES MF W4 1% 12K
R111 1H356 RES MF W4 1% 56K
R112 1H410 RES MF W4 1% 100K
R113 1H410 RES MF W4 1% 100K
R114 1H410 RES MF W4 1% 100K
R115 1H315 RES MF W4 1% 15K
R116 1H522 RES MF W4 1% 2M2
Page 7
L870 Phono Board Parts List Issue 2.0
Designator Part Description
R117 1H522 RES MF W4 1% 2M2
R118 1H022 RES MF W4 1% 22R
R119 1H022 RES MF W4 1% 22R
R120 1H022 RES MF W4 1% 22R
R121 1H022 RES MF W4 1% 22R
R122 1H339 RES MF W4 1% 39K
R123 1H010 RES MF W4 1% 10R
R124 1H256 RES MF W4 1% 5K6
R200 1H133 RES MF W4 1% 330R
R201 1H110 RES MF W4 1% 100R
R202 1H110 RES MF W4 1% 100R
R204 1H110 RES MF W4 1% 100R
R205 1H110 RES MF W4 1% 100R
R206 1H110 RES MF W4 1% 100R
R208 1H347 RES MF W4 1% 47K
R209 1H312 RES MF W4 1% 12K
R210 1H312 RES MF W4 1% 12K
R211 1H356 RES MF W4 1% 56K
R212 1H410 RES MF W4 1% 100K
R213 1H410 RES MF W4 1% 100K
R214 1H410 RES MF W4 1% 100K
R215 1H315 RES MF W4 1% 15K
R216 1H522 RES MF W4 1% 2M2
R217 1H522 RES MF W4 1% 2M2
R218 1H022 RES MF W4 1% 22R
R219 1H022 RES MF W4 1% 22R
R220 1H022 RES MF W4 1% 22R
R221 1H022 RES MF W4 1% 22R
R222 1H339 RES MF W4 1% 39K
R223 1H010 RES MF W4 1% 10R
R224 1H256 RES MF W4 1% 5K6
SK1 8D230 PHONO SKT 2-WAY HOR EMC GOLD
SK2 8K2408 8-WAY AMP CT CONN
SW100 A1013 SW PUSH 4PCO
TR100 4A556 TRANS LF SS P BC556B
TR101 4A556 TRANS LF SS P BC556B
TR102 4A556 TRANS LF SS P BC556B
TR103 4A556 TRANS LF SS P BC556B
TR104 4A556 TRANS LF SS P BC556B
TR105 4A556 TRANS LF SS P BC556B
TR106 4A1085 TRANS LF SS P 2SA1085
TR107 4A1085 TRANS LF SS P 2SA1085
TR108 4A546 TRANS LF SS N BC546B
TR109 4A546 TRANS LF SS N BC546B
TR110 4A546 TRANS LF SS N BC546B
TR111 4A546 TRANS LF SS N BC546B
TR112 4A546 TRANS LF SS N BC546B
TR113 4A546 TRANS LF SS N BC546B
TR114 4A546 TRANS LF SS N BC546B
TR200 4A556 TRANS LF SS P BC556B
TR201 4A556 TRANS LF SS P BC556B
TR202 4A556 TRANS LF SS P BC556B
TR203 4A556 TRANS LF SS P BC556B
TR204 4A556 TRANS LF SS P BC556B
TR205 4A556 TRANS LF SS P BC556B
TR206 4A1085 TRANS LF SS P 2SA1085
TR207 4A1085 TRANS LF SS P 2SA1085
TR208 4A546 TRANS LF SS N BC546B
TR209 4A546 TRANS LF SS N BC546B
TR210 4A546 TRANS LF SS N BC546B
TR211 4A546 TRANS LF SS N BC546B
TR212 4A546 TRANS LF SS N BC546B
TR213 4A546 TRANS LF SS N BC546B
TR214 4A546 TRANS LF SS N BC546B
Page 8
87654321
D
C
LEFT CHANNEL
C1
100N CD
SK1
PHONO2HG
EMC
1
0V_SIG
0V_SIG
Q_1
Q_2
L870C2_2.0.SCH
LEFT IN LEFT OUT
RIGHT CHANNEL
L870C3 2.0.SCH
RIGHT N RIGHT OUT
Q_3
Q_4
+15V
Q_6
-15V
SK2
1
2
3
4
5
6
7
8
AMPCT8
0V_HF0V_SIG
Q_5
Q_7 Q_8
D
C
B
A
PCB1
PCB
L870PB_2
1 2 3 4 5 6 7 8
EL1
Update Box
UPDATE_BOX
DRAWING TITLE
A85 PHONO STAGE - TOP LEVEL
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
Notes
Filename
G:\DATA\ECO\ECO AGENDA\01 1070 l870 A85 PHONO ISSUE2\L870 2.0.ddb - L870c1 2.0.PRJ
Circuit Diagram
01_1070 JAG 17/4/01 updated pcb and scm 2
00_1051 JAG 22/3/01 PRODUCTION ISSUE 1
ECO No. DESCRIPTION OF CHANGE
INITIALS
Date Printed
DATE
Drawn by:
JBR23-Apr-2001
1 3Sheet of
DRAWING NO.
L870C1
B
A
ISSUE
Page 9
87654321
+
C102
100U SILMIC
R111
56K MF
R124
5K6 MF
R123
10R MF
C119
100P PP
C101
1N0 PP
C110
4N7 PP
C120
1N0 PP
C112
10N PP AX
C111
10N PP AX
R112
100K MF
C105
100N PE
Q 101
R113
100K MF
R114
100K MF
R115
15K MF
TL071CD
R101
100R MF
TR102
BC556B
TR108
BC546B
R116
2M2 MF
74
IC100
3
6
C118
2
10U NP
R117
2M2 MF
TR104
BC556B
D
TR100
BC556B
+
C100
22U EL
R109
12K MF
R110
12K MF
LEFT IN
C
R104
100R MF
SW100B
4PCO
5
6
C108
470P PPW
4
R108
47K MF
C109
100P PPW
TR106
2SA1085
R100
330R MF
TR101
BC556B
TR107
2SA1085
C115
N3 PP
SW100D
4PCO
R105
100R MF
101112
Q_102
R102
100R MF
TR103
BC556B
D100
1N4148
C104
100N PE
0V_SIG0V_HF
C106
100N PE
+15V
TR109
BC546B
R118
22R MF
R119
22R MF
TR105
BC556B
C113
1U0 PE
0V_SIG
R122
39K MF
D
C
LEFT OUT
0V_SIG0V_SIG
B
TR110
BC546B
D101
1N4148
R120
22R MF
A
1 2 3 4 5 6 7 8
TR111
BC546B
D102
1N4148
R121
22R MF
DRAWING TITLE
A85 PHONO STAGE - LEFT CHANNEL
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
C116
470P PPW
23425
TR112
BC546B
+
C103
100U SILMIC
Notes
Filename
G:\DATA\ECO\ECO AGENDA\01 1070 l870 A85 PHONO ISSUE2\L870 2.0.ddb - L870C2 2.0.SCH
TR113
BC546B
TR114
BC546B
R106
100R MF
0V_SIG0V_HF
Circuit Diagram
C117
470P PPW
C107
100N PE
Q_103
-15V
01_1070 JAG 17/4/01 updated pcb and scm 2
00_1051 JAG 22/3/01 PRODUCTION ISSUE 1
ECO No. DESCRIPTION OF CHANGE
INITIALS
Date Printed
DATE
Drawn by:
JBR23-Apr-2001
2 3Sheet of
DRAWING NO.
L870C2
B
A
ISSUE
Page 10
87654321
+
C202
100U SILMIC
R211
56K MF
R224
5K6 MF
9
R223
10R MF
C219
100P PP
C201
1N0 PP
C210
4N7 PP
C220
1N0 PP
C212
10N PP AX
C211
10N PP AX
R212
100K MF
C205
100N PE
Q 201
R213
100K MF
R214
100K MF
R215
15K MF
TL071CD
R201
100R MF
TR202
BC556B
TR208
BC546B
R216
2M2 MF
74
IC200
6
3
2
C218
10U NP
R217
2M2 MF
TR204
BC556B
D
TR200
BC556B
+
C200
22U EL
R209
12K MF
R210
12K MF
RIGHT IN
C
R204
100R MF
SW100A
4PCO
2
3
C208
470P PPW
1
R208
47K MF
C209
100P PPW
TR206
2SA1085
R200
330R MF
TR201
BC556B
TR207
2SA1085
R205
100R MF
C215
1N3 PP
7
SW100C
4PCO
8
Q_202
R202
100R MF
TR203
BC556B
D200
1N4148
C204
100N PE
0V_SIG0V_HF
C206
100N PE
+15V
TR209
BC546B
R218
22R MF
R219
22R MF
TR205
BC556B
C213
1U0 PE
0V_SIG
R222
39K MF
D
C
RIGHT OUT
C217
0V_SIG0V_SIG
B
TR210
BC546B
D201
1N4148
R220
22R MF
A
TR211
BC546B
D202
1N4148
R221
22R MF
DRAWING TITLE
A85 PHONO STAGE - RIGHT CHANNEL
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
1 2 3 4 5 6 7 8
Cambridge CB5 9PB
470P PPW
TR212
BC546B
+
C203
100U SILMIC
Notes
Filename
G:\DATA\ECO\ECO AGENDA\01 1070 l870 A85 PHONO ISSUE2\L870 2.0.ddb - L870C3 2.0.SCH
TR213
BC546B
TR214
BC546B
R206
100R MF
0V_SIG0V_HF
Circuit Diagram
470P PPWC216
C207
100N PE
Q_203
-15V
01_1070 JAG 17/4/01 updated pcb and scm 2
00_1051 JAG 22/3/01 PRODUCTION ISSUE 1
ECO No. DESCRIPTION OF CHANGE
INITIALS
Date Printed
DATE
Drawn by:
JBR23-Apr-2001
3 3Sheet of
DRAWING NO.
L870C3
B
A
ISSUE
Page 11
Amplifier + PSU
Board
L882
Contents
!
Circuit description
!
Component overlay
!
Parts list
!
Circuit diagrams
Page 12
Amplifier & PSU Circuit Description
Refer to L882 circuit diagrams
This is the printed circuit board that provides the power
supply and output s tage amp lifiers for the A32 integrat ed and
P35 power amplifiers.
Its function is to:
! Drive the loudspeakers
! Provide an (always on) au xiliary 5VDC supply for the
micro controller and display interface
! Receive logic signals from the micro controller to turn
on the main amplifier supply relay (mains) and connect
either pair of speaker output sockets
! Send logic signals t o the micro controller p ertaining t o
the state of th e amplifiers (sh ort circuit protect ion, DC
offset protection, thermal protection)
! Receive and demodulate RC5 remote style control
codes via th e rear panel jack and transmit them t o the
micro controller
! Send a 12V trigger output via the rear panel jack for
control of an auxiliary power amp when the unit is on
! Receive a 12V trigger input from th e rear jack (for use
in the power amp only version)
! Drive a pair of headphones via attenuating resistor
networks The power amplifier is a symmetrical, class B,
bipolar junction transistor output, current-feedback
design (of which more later) with DC-coupled signal
and feedback paths, featuring an active integrating
voltage servo to control DC offsets.
It features ‘instantaneous’ safe operating area protection in
addition to sendi ng a sign a l to th e micro to turn off th e out put
relays in the even t of user or thermal ove rload. Since it i s a
DC-coupled design, the unit senses DC at the output and
triggers the micro to turn off the loudspeaker relays in the
event of excessive levels (possibly due to a faulty source
component or short circuit output transistor).
The output stage uses Sanken specialised ‘audio amplifier’
power bipolar Darlin gton transist ors which are optimi sed for
use with this type of topology. Consequently the unit has
excellent measured performance in terms of noise, slew rate,
output impedance and distortion (harmonic and
intermodulated) and is essentially load invariant (to a first
order the measured performance is independent of the load
impedance).
L882 Circuit Sheet 1
The audio input to the amplifier is connected to SK102
(which connects to the output of the preamp PCB). This
signal is passed on via SK104A which forms the preamp out
connection to the outside world.
SK104B provides the power amp input connection, with
switchSW100 selecting between pre / power and integrated
modes. The unit is wired as a preamp / power amp
combination with the switch depressed, allowing the user to
insert a processor or other function (e.g. graphic EQ) between
the output of the preamp and the input of the power amp.
With the switch in the ‘out’ position the power amp input
socket is ignored and the input to the power amp is conn ected
internally to the output of the preamp. PL100 and PL101 are
‘handbag’ links fitted to the power amp only version to
connect both pairs of phono sockets in parallel for daisy
chaining (as there is no preamp output on a power amp).
Relays RLY100 and RLY101 switch the two pairs of
loudspeaker output sockets and are controlled by the micro
lines describes above. Transistors TR100 and TR101 operate
in ‘constant current sink ’ mode which allow relay current to
be approximately constant although the main power supply
rails will vary with mains input and load conditions. The
current is around 20mA per relay.
Star point SP100 is the ground ‘mecca’ for the entire
amplifier (comp rising all three PCB s within the uni t). All
of the separately named grounds are joined explicitly at
this point. Different named grounds are used to ensure that
no two ‘different’ grounds share copper, which could
compromise the noise, distortion or crosstalk performance
of the amplifier.
The loudspeaker output signals are passed to socket
SK106 which connects to SK107 and onto the headphone
output via the attenuation resistors R103 thru R106.
The hierarchy containing the other sheets is self
explanatory. Each of the port names shown on the top
sheet connec ts to the port of th e same name on th e lower
sheets.
L882 Circuit Sheet 2
This sheet contains the power supplies, the rear panel jack
socket trigger circuits, the standby relay control and the
‘interface’ci rcuits between t he output signa ls of the power
amplifiers and the inputs expected by the micro processor.
The mains input enters the unit at SK203, with capacitors
C205 and C206 acting as conducted RF suppression. The
earth connection is passed on to the chassis (for safety
reasons th e cha ssi s met alwork remai ns c onn ected to mains
power earth at all times). Switch SW200 is the voltage
selector switch, allowing the unit to be operated in 230V
or 115V mains countries by switching the dual-primary
mains transformers between series and parallel winding.
Varistors VR200 and VR201 act to prevent over-voltag e
surges from damaging the unit. If the user selects 115V
operation and then connects the unit to a 230V supply, the
varistors will go to a low impedance and blow the primary
fuses. Any very high voltage line transients will also be
suppressed, helping to eliminate transformer isolation
breakdown.
Relay RLY200 switches the primary side of the mains
transformer, allowing the micro to control the on / off
status of the amplifier. Its contacts are snubbed by
capacitors C207 and C208 (to eliminate switching spark
transients and prolong relay lifespan). The primary
windings of the toroidal mains transformer connect to
SK204.
PCB mounted transformer TX200 is powered all the time
that mains i s presen t on SK203 , irres pect ive of the on / off
status of the amplifier. This is to ensure that the micro
processor is always operational and can thus control the
mains switching for the main amplifier. Secondary fuse
F202 limits the current in the event of a failure mode, as
the short circuit primary current of TX200 would be
insufficient to blow the mains fuses.
Diodes D200 thru D203, C227 and IC201 provide the
5VDC supply which powers the micro and display PCB
and the rela y coils. C224 is to reduce diode noise being
transmitted back through the leakage capacitance of
TX200.
The mains transformer secondary winding is connected to
SK200. This is a centre tapped winding, and is used with
full bridge rect ifier BR200 to produce the ma in positive
and negative su pplies for the p ower amp. C209 and C210
are the large reservoir capacitors, with C211 and C212
acting as high frequency decouplers. The main power
supply rails and ground are accessible on SK205 for future
module expansion.
Page 13
The circuitry around SK201A and IC200 is to receive and
demodulate remote control commands sent in via the rear
panel jack socket. This is for multi-room applications. L200
and C200 form a parallel resonant circuit at approximately
37kHz. The output from this bandpass filter is passed into
IC200A wh ere it is ‘chopped’ and fed to IC200B to provide
the output sign al.
SK201B is a 13VDC signal trigger output which is active
whenever the amplifier is powered up. R218 and DZ207 /
C223 provide a reference voltage which is buffered by
TR200. TR201 and R217 act as a current limit and prevent
damage due to a short circuit on the output of SK201B. The
maximum current is approximately 65mA.
TR203 and TR202 are a complementary Darlington pair
which turn on mains relay RLY200 when activated by a
signal from the microprocessor.
TR204 and its associated components are to detect whenever
AC mains is present at the IEC socket. This is to notify the
microprocessor i f the user has unplugged the mains cord , so
that it can take the necessary a ction (muting all t he outputs
and switching off the mains rela y). The reservoir capacitors
should last at least 4 mains cycles which gives the
microprocessor plenty of time for a cont rolled shutdown.
TR204 forms a monostable circuit. Each cycle of AC turns on
TR204 via R211. TR204 then ‘shunts’ C229 ensuring that it
is kept at a low potential. If more than one mains cycle is
missing, then R 219 charges up C229 sufficiently to t rigger
Schmitt inverter IC202E thus passing on a logic signal to the
microprocessor. The use of a Schmitt inverter for IC202 is to
ensure that the micro receives ‘clean’ logic levels - the
hysteresis voltage (about 0.5V) is sufficient to prevent circuit
noise from producing a string of ‘ghost’ signals when
analogue levels are near the threshold point.
TH200 is a positive tempco thermistor placed adjacent to the
heatsink on wh ich the outp ut transistors are mounted. Wh en
the tempera ture of th e thermis tor exceeds 90 degrees Celsius
the thermistor goes to a high impedance and so the input to
IC202F goes low. This triggers a HIGH output to the micro
indicating thermal overload.
The VI protection signals from the left and right channels
pass into IC202A and IC202B respectively, to be ‘cleaned
up’ via the Schmitt trigger. They are then NOR’d using
TR205 which send s a HIGH signal to t he micro in the even t
of either chann el sufferi ng a s hort c ircuit or cu rrent overloa d.
Exactly the same approach is used for the DC fault lines
using IC202C and IC202D.
L882 Circuit Sheet 3
This is the main audio power amplifier circuit. The amplifier
is a class B design, which uses SAP ‘audio’ transistors in a
symmetrical current feedback configuration. Input and
feedback paths are DC coupled and there is an active
integrating servo to remove DC offsets from the output.
The basic principle of operation is follows:
The input signal is amplified by a factor of 2 in IC300A. This
drives a 44˜ impedance to ground causing the supply pin
currents to change with the signal level. These changing
supply pin currents are then ‘reflected’ by a pair of
complementary Wilson mirrors and passed on to a series of
buffer transistors before being connected to the load. The
‘feedback current’ flows back from the output terminal via
R331 and R332 and attempts to provide the current necessary
to allow IC300A to swing its output without drawing
excessive current from its supply pins, thus making the
change in supply current very small indeed. This is why the
term ‘current feedback’ is used - it is the current flowing in
the feedback resistors that sets the overall gain of the
amplifier.
IC300B acts as an in verti n g in t egrat or an d its purp ose i s t o
remove DC from the loudspeaker output. Any positive DC
offset will caus e the outpu t of IC300B to go negat ive, thus
increasing the current in its negative supply pin and
pulling the output voltage back towards zero. R330 and
C317 set the time constant of this integrator (0.47 seconds)
so that audio frequency components are ignored and only
DC and subsonic frequencies are removed.
The input to the amplifier is limited to ±5.4V via back-toback zener di odes DZ302 and DZ303. This is to prevent
the user from grossly overdriving the input to the amplifier
and possibly causing damage. The diodes appear before
series resist or R324 so that their va riable c apaci tance d oes
not introduce high frequency harmonic distortion.
R324, R327 and C316 act as an input filter - this is a first
order low pass filter with a corner frequency of around
340kHz to prevent RF signa ls from being in ject ed into the
front end of the amplifier. The corner frequency was
chosen such that the ph ase shift int roduced is less than 5˜
at 20kHz (considered by the AES to be the minimum
perceptib le relative amou nt by the hu man ear). The in put
impedance of the amplifier is 23kW at DC, falling to
around 14kW at 20kHz.
Operational amplifier IC300A is acting as a non-inverting
gain of 2, driving the input signal into a 44W impedance to
ground via R322 and R33 7. Its output voltage will b e an
accurate amp lification of its input volta ge (i.e. the signal
on pin 1 should look id entic al to that on pin 3 but at twic e
the amplitude). The op-amp is used in a slightly unusual
configuration here, in that its power supply pins are used
as a (current) output, and its output pin is used as a
(current) feedback.
Transistors TR311 and TR303 supply the ±15V rails to the
op-amp, and act as cascades to pass its supply pin currents
through to the current mirrors, whi ch sit at a potential too
high for the op-amp to be c onnected directly.
TR300, TR301 and TR321 form a PNP Wilson current
mirror, which reflects the current sunk by the positive
supply pin of IC300. Likewise TR314, TR315 and TR320
form an NPN Wilson current mirror, which reflects the
current sourced by the negative supply pin of IC300.
R315 thru R318 provide emitter degeneration of
approximately 300mV for the current mirrors (as they pass
about 3mA DC in quiescent conditions), to ensure accurate
operation independent of the small variations between the
transistors in the current mirrors. They also ensu re that the
current passing down the next stage is reasonably constant
as the internal temperature of the amplifier changes,
VBE
swamping out small thermal variations in the
of the
mirror transistors.
R319 and R320 slightly decouple the rails to the current
mirrors from the main power rails of the amplifier, to
allow the bootstrap circuit to operate. The bootstrap
consists of C302 and C3 06 with met al film power r es is tors
R352 and R353. The bootstrap is provided to allow the
power supply rails of the current mirrors to go up and
down slightly with the output signal into the loudspeaker.
This enables the driver stage to fully sat urate the output
transistors and thus give the greatest power output and best
thermal efficiency for any gi ven power rail voltage. The
voltage on the ‘i nsid e’ end of R3 19 and R3 20 will va ry by
about 12 volts peak to peak at full output power, rising
above the main power rails during signa l peaks.
Page 14
C307 and C308 with R333 and R335 provide the
compensation necessary to ensure stability when the loop is
closed. The y are Mill er cap acitor s which dramat icall y reduce
the transim pedance (i.e. current to volt age gain) of the current
mirrors at high frequencies. The present value of 47pF
provides for a unity gain open loop bandwidth of around
75MHz, whilst ensuri ng a closed loop ga in margin of around
6dB (note that gain margin in a current feedback design is not
dependent on system bandwidth to a first order
approximation ). R333 and R335 provide a ‘zero’ in the open
loop frequency response which is tailored to give the best
time domain performance (i.e. to make high frequency square
waves look square with minimal ringing or overshoot).
DZ304 and C311 provide a fixed 4.7V bias voltage to allow
the following stages to operate correctly. C311 is there to
ensure that both halves of the following stage receive an
equal AC signal component at high frequency.
TR310 and TR307 are the ‘pre-driver’ t ransistors, which act
to buffer th e outputs from th e preceding stage and drive the
Darlington out put power transistors. TR30 9 an d R3 21 act as a
current limit, to ensure tha t the emi tt er curren t of TR310 d oes
not exceed 30mA in a fault condition. TR306 and R323
provide the same function for TR307.
R338 and R339 are to loosely c ouple the ou tputs of th e predriver stage to the inputs of the Darlington power output
devices. This is so that the inbuilt temperature sensing diodes
of the outpu t transist ors can accur ately control t he quiesc ent
current of th e outpu t stage a s the junct ion temp erature of t he
power devices va ries . C 3 12 and C318 en su re t h at bot h halves
of the output stage receive an equal AC signal component.
The output transistors are TR318 and TR319. These are
Sanken SAP15N and SAP15P devices respectively. They are
specially designed for audio power amplifier use. In addition
hFE
to high current gain (Darlington with a typi cal
of 20,000)
they provide an inbuilt emitter resistor (thick film power
resistor of 0W22) and temperature sensing diodes which
VBE
closely and rapidly track the
versus temperature
characteristic of the power transi stors, allo wing for easy, fastresponding and reasonably accurate control of quiescent
current.
RV300 is for fine trimming of the quiescent current. PL300
provides a convenient measuring point for this, which is
short-circuit protected in the event of a slip with the
multimeter probe! All of the remaining circuitry to the right
of TR318 and TR319 is essentially for output stage
protection...
Transistors TR312 and TR304, along with the network of
resistors and capacitors to which they are connected, provide
instantaneou s overload p rotection of the ou tput sta ge. This is
a conventional single slope VI protection scheme, which
allows much greater curren t to be delivered into a rated load
than into a short circuit. The values allow for 18A peak
delivery (at clip) into a purely resistive load, 7A peak (at clip)
into a purely capacitive load and around 4A peak into a short
circuit. R345, C303, R346 and C304 allow these values to be
doubled for short transient bursts (approximately 2.7
milliseconds) so that impulsive musical transients can be
delivered cleanly with minimal risk of damaging the output
transistors.
TR313, TR302 and their associated components send a signal
to the microprocessor when the instantaneous protection
circuits are having to work ‘hard’ to prevent amplifier
overload. Th is instructs the micro that th e user is severely
abusing the amplifier and will switch off the loudspeaker
relays to prevent possible permanent damage. In reality, if
you short circui t the outpu ts at any ap precia ble volum e level,
this circuit will trigger a nd the microprocessor will turn off
the loudspeaker relays and send a signal t o the user.
R308, R314 and C320 form a low pa ss filter from which
the DC detection circuits can sense excessive DC at the
loudspeaker outputs. If there is any po sitive DC present,
then TR316 will turn on, which turns on TR305 and thus
activates th e DC protection lin e to the micro, turnin g off
the loudspeaker relays.
If there is a ny negati ve DC presen t, then TR 308 will tu rn
on, which turns on TR317 which then turns on TR305 in
turn, causin g the same effect.
R350 and C319 are the Zobel network which is provided
to ensure the amplifier ‘sees’ a consta nt and resistive load
at very high frequencies, to aid stability, although the
amplifier will be stable without the Zobel fitted.
C313 locally couples the ‘high frequency’ and loudspeaker
ground returns together at the output to overcome the
effects of track inductance back to the star point. C309
couples the ‘h igh frequency’ and signal grounds together
at the input for the same reason.
D303 and D304 a re ‘flyback’ di odes to protect the output
transistors from reverse bias when the amplifier is heavily
clipped into an indu ct i ve loa d (such as a loud s p eaker voi ce
coil!)
Sheet 4 is an identical copy of sheet 3 so I will not
describe it separ ately.
Page 15
Page 16
L882 Amplifier and PSU Board Parts List Issue 3.0
Designator Part Description
BR200 3BGBU8D BRIDGE RECTIFIER 8A 200V
C100 2C210 MLC 1N0 50V X7R 10% SM
C200 2D168 PPRO 680P 5% 63V RA
C201 2C410 MLC 100N 50V X7R 10% SM
C202 2C410 MLC 100N 50V X7R 10% SM
C203 2C410 MLC 100N 50V X7R 10% SM
C204 2C410 MLC 100N 50V X7R 10% SM
C205 2K233 SUPPR CAP 3N3 250V
C206 2K233 SUPPR CAP 3N3 250V
C207 2K233 SUPPR CAP 3N3 250V
C208 2K233 SUPPR CAP 3N3 250V
C209 2N910A ELST 10m 63V RA 35mm
C210 2N910A ELST 10m 63V RA 35mm
C211 2H410 PCRB 100N 100V 10% RA 5mm
C212 2H410 PCRB 100N 100V 10% RA 5mm
C213 2C310 MLC 10N 50V X7R 10% SM
C214 2C310 MLC 10N 50V X7R 10% SM
C215 2C310 MLC 10N 50V X7R 10% SM
C216 2C310 MLC 10N 50V X7R 10% SM
C217 2C310 MLC 10N 50V X7R 10% SM
C218 2C310 MLC 10N 50V X7R 10% SM
C219 2C310 MLC 10N 50V X7R 10% SM
C220 2C410 MLC 100N 50V X7R 10% SM
C221 2C310 MLC 10N 50V X7R 10% SM
C222 2N610 ELST 10U 50V
C223 2N610 ELST 10U 50V
C224 2A410 CERD 100N 63V 20% RA
C225 2A410 CERD 100N 63V 20% RA
C226 2A410 CERD 100N 63V 20% RA
C227 2N833 ELST 3M3 25V
C228 2N810A ELST 1M0 10V
C229 2N622 ELST 22U 63V
C230 2C310 MLC 10N 50V X7R 10% SM
C231 2C210 MLC 1N0 50V X7R 10% SM
C232 2C410 MLC 100N 50V X7R 10% SM
C233 2N610 ELST 10U 50V
C234 2D422 220NF CLASS X2 CAP 275VRMS
C235 2C210 MLC 1N0 50V X7R 10% SM
C300 2N710 ELST 100U 25V
C301 2N710 ELST 100U 25V
C302 2N710B ELST 100U 100V
C303 2N710 ELST 100U 25V
C304 2N710 ELST 100U 25V
C305 2N610 ELST 10U 50V
C306 2N710B ELST 100U 100V
C307 2C110 MLC 100P 50V NPO 5% SM
C308 2C110 MLC 100P 50V NPO 5% SM
C309 2C410 MLC 100N 50V X7R 10% SM
C310 2C410 MLC 100N 50V X7R 10% SM
C311 2H410 PCRB 100N 100V 10% RA 5mm
C312 2C310 MLC 10N 50V X7R 10% SM
C313 2C410 MLC 100N 50V X7R 10% SM
C314 2C410 MLC 100N 50V X7R 10% SM
C315 2C410 MLC 100N 50V X7R 10% SM
C316 2D147W PPRO W 470P 63V 5% RA
C317 2K447 PEST 470N 63V 10%
C318 2N610 ELST 10U 50V
C319 2K410 PEST 100N 63V 10%
C320 2V710 ELST NON POLAR 100UF 16V
C400 2N710 ELST 100U 25V
C401 2N710 ELST 100U 25V
C402 2N710B ELST 100U 100V
Page 17
L882 Amplifier and PSU Board Parts List Issue 3.0
Designator Part Description
C403 2N710 ELST 100U 25V
C404 2N710 ELST 100U 25V
C405 2N610 ELST 10U 50V
C406 2N710B ELST 100U 100V
C407 2C110 MLC 100P 50V NPO 5% SM
C408 2C110 MLC 100P 50V NPO 5% SM
C409 2C410 MLC 100N 50V X7R 10% SM
C410 2C410 MLC 100N 50V X7R 10% SM
C411 2H410 PCRB 100N 100V 10% RA 5mm
C412 2C310 MLC 10N 50V X7R 10% SM
C413 2C410 MLC 100N 50V X7R 10% SM
C414 2C410 MLC 100N 50V X7R 10% SM
C415 2C410 MLC 100N 50V X7R 10% SM
C416 2D147W PPRO W 470P 63V 5% RA
C417 2K447 PEST 470N 63V 10%
C418 2N610 ELST 10U 50V
C419 2K410 PEST 100N 63V 10%
C420 2V710 ELST NON POLAR 100UF 16V
D100 3B4003 RECTIFIER 1N4003F 1A 200V
D101 3B4003 RECTIFIER 1N4003F 1A 200V
D200 3B4003 RECTIFIER 1N4003F 1A 200V
D201 3B4003 RECTIFIER 1N4003F 1A 200V
D202 3B4003 RECTIFIER 1N4003F 1A 200V
D203 3B4003 RECTIFIER 1N4003F 1A 200V
D205 3AS16W DIODE SS SM BAS16W
D206 3AS16W DIODE SS SM BAS16W
D300 3AS16W DIODE SS SM BAS16W
D301 3AS16W DIODE SS SM BAS16W
D302 3AS16W DIODE SS SM BAS16W
D303 3B4003 RECTIFIER 1N4003F 1A 200V
D304 3B4003 RECTIFIER 1N4003F 1A 200V
D400 3AS16W DIODE SS SM BAS16W
D401 3AS16W DIODE SS SM BAS16W
D402 3AS16W DIODE SS SM BAS16W
D403 3B4003 RECTIFIER 1N4003F 1A 200V
D404 3B4003 RECTIFIER 1N4003F 1A 200V
DZ204 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ207 3CW315V ZENER 15V OW35 SM SOT23
DZ300 3CW315V ZENER 15V OW35 SM SOT23
DZ301 3CW315V ZENER 15V OW35 SM SOT23
DZ302 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ303 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ305 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ306 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ400 3CW315V ZENER 15V OW35 SM SOT23
DZ401 3CW315V ZENER 15V OW35 SM SOT23
DZ402 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ403 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ405 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ406 3CW34V7 ZENER 4V7 OW 35 SM SOT23
EL 8M101 EARTH LEAD
F200 C12207 FUSE 20mm 2A AS
F200 F022 INS COVER PCB FUSEHOLDER
F200 8S004 FUSEHOLDER 20mm PCB
F201 F022 INS COVER PCB FUSEHOLDER
F201 8S004 FUSEHOLDER 20mm PCB
F201 C12207 FUSE 20mm 2A AS
F202 C3501 FUSE R452 T500mA
HS200 F008 HEATSINK TO220 8.6 DEGC/W
HS200 F006 HEATSINK CLIP TO220 13/8.6 DC/W
IC200 5M393AD IC COMPARATOR SM DUAL LM393A
IC201 5D7805 IC VREG POS 7805
Page 18
L882 Amplifier and PSU Board Parts List Issue 3.0
Designator Part Description
IC202 5J7414D SURFACE MOUNT HEX SCHMITT TRIGGER
IC300 5B072D IC AUDIO SM DUAL TL072
IC400 5B072D IC AUDIO SM DUAL TL072
L200 7D327 27mH INDUCTOR
L300 7D002C INDUCT 2U2 12x20mm
L400 7D002C INDUCT 2U2 12x20mm
PCB L882PB_3 PRINTED CIRCUIT BOARD
PL100 8K6201 2WAY MOLEX VERT MALE CONNECTOR
PL101 8K6201 2WAY MOLEX VERT MALE CONNECTOR
PL300 8K6201 2WAY MOLEX VERT MALE CONNECTOR
PL400 8K6201 2WAY MOLEX VERT MALE CONNECTOR
R100 1H010 RES MF W4 1% 10R
R101 1A110 RES SM W4 1% 100R 1206
R102 1A110 RES SM W4 1% 100R 1206
R103 1.00E+133 RES CF 1W 330R 5%
R104 1.00E+133 RES CF 1W 330R 5%
R105 1.00E+110 RES CF 1W 100R 5%
R106 1.00E+110 RES CF 1W 100R 5%
R107 1A122 RES SM W4 1% 220R 1206
R108 1A122 RES SM W4 1% 220R 1206
R200 1A210 RES SM W4 1% 1K0 1206
R201 1A210 RES SM W4 1% 1K0 1206
R202 1A210 RES SM W4 1% 1K0 1206
R203 1A210 RES SM W4 1% 1K0 1206
R204 1A210 RES SM W4 1% 1K0 1206
R205 1A210 RES SM W4 1% 1K0 1206
R206 1A210 RES SM W4 1% 1K0 1206
R207 1A210 RES SM W4 1% 1K0 1206
R208 1A310 RES SM W4 1% 10K 1206
R209 1A310 RES SM W4 1% 10K 1206
R210 1A310 RES SM W4 1% 10K 1206
R211 1A310 RES SM W4 1% 10K 1206
R212 1A247 RES SM W4 1% 4K7 1206
R213 1A247 RES SM W4 1% 4K7 1206
R214 1A247 RES SM W4 1% 4K7 1206
R215 1A247 RES SM W4 1% 4K7 1206
R216 1A247 RES SM W4 1% 4K7 1206
R217 1A010 RES SM W4 1% 10R 1206
R218 1A310 RES SM W4 1% 10K 1206
R219 1A218 RES SM W4 1% 1K8 1206
R220 1A010 RES SM W4 1% 10R 1206
R221 1A010 RES SM W4 1% 10R 1206
R222 1A310 RES SM W4 1% 10K 1206
R223 1A310 RES SM W4 1% 10K 1206
R224 1A218 RES SM W4 1% 1K8 1206
R225 1A218 RES SM W4 1% 1K8 1206
R226 1A147 RES SM W4 1% 470R 1206
R227 1A210 RES SM W4 1% 1K0 1206
R228 1A410 RES SM W4 1% 100K 1206
R229 1A410 RES SM W4 1% 100K 1206
R230 1A215 RES SM W4 1% 1K5 1206
R231 1K515 RES W25 5% VR25 1M5
R300 1A310 RES SM W4 1% 10K 1206
R301 1A310 RES SM W4 1% 10K 1206
R302 1A310 RES SM W4 1% 10K 1206
R303 1A310 RES SM W4 1% 10K 1206
R304 1A310 RES SM W4 1% 10K 1206
R305 1A310 RES SM W4 1% 10K 1206
R306 1A310 RES SM W4 1% 10K 1206
R307 1A310 RES SM W4 1% 10K 1206
R308 1A310 RES SM W4 1% 10K 1206
R309 1A310 RES SM W4 1% 10K 1206
Page 19
L882 Amplifier and PSU Board Parts List Issue 3.0
Designator Part Description
R310 1A247 RES SM W4 1% 4K7 1206
R311 1A310 RES SM W4 1% 10K 1206
R312 1A310 RES SM W4 1% 10K 1206
R313 1A310 RES SM W4 1% 10K 1206
R314 1A247 RES SM W4 1% 4K7 1206
R315 1A110 RES SM W4 1% 100R 1206
R316 1A110 RES SM W4 1% 100R 1206
R317 1A110 RES SM W4 1% 100R 1206
R318 1A110 RES SM W4 1% 100R 1206
R319 1A110 RES SM W4 1% 100R 1206
R320 1A110 RES SM W4 1% 100R 1206
R321 1A022 RES SM W4 1% 22R 1206
R322 1A022 RES SM W4 1% 22R 1206
R323 1A022 RES SM W4 1% 22R 1206
R324 1A210 RES SM W4 1% 1K0 1206
R325 1A210 RES SM W4 1% 1K0 1206
R326 1A210 RES SM W4 1% 1K0 1206
R327 1A322 RES SM W4 1% 22K 1206
R328 1A247 RES SM W4 1% 4K7 1206
R329 1A247 RES SM W4 1% 4K7 1206
R330 1A510 RES SM W4 1% 1M0 1206
R331 1A215 RES SM W4 1% 1K5 1206
R332 1A218 RES SM W4 1% 1K8 1206
R333 1A233 RES SM W4 1% 3K3 1206
R334 1A322 RES SM W4 1% 22K 1206
R335 1A233 RES SM W4 1% 3K3 1206
R336 1A322 RES SM W4 1% 22K 1206
R337 1A022 RES SM W4 1% 22R 1206
R338 1A115 RES SM W4 1% 150R 1206
R339 1A115 RES SM W4 1% 150R 1206
R340 1A410 RES SM W4 1% 100K 1206
R341 1A133 RES SM W4 1% 330R 1206
R342 1A133 RES SM W4 1% 330R 1206
R343 1A110 RES SM W4 1% 100R 1206
R344 1A110 RES SM W4 1% 100R 1206
R345 1A000 RES SM W4 1% 0R0 1206
R346 1A000 RES SM W4 1% 0R0 1206
R347 1A110 RES SM W4 1% 100R 1206
R348 1A110 RES SM W4 1% 100R 1206
R349 1A110 RES SM W4 1% 100R 1206
R350 1C856 RES CF 2W 5R6 5%
R351 1H010 RES MF W4 1% 10R
R352 1J147 RES 2W MF 5% 470R
R353 1J147 RES 2W MF 5% 470R
R354 1A210 RES SM W4 1% 1K0 1206
R355 1A268 RES SM W4 1% 6K8 1206
R400 1A310 RES SM W4 1% 10K 1206
R401 1A310 RES SM W4 1% 10K 1206
R402 1A310 RES SM W4 1% 10K 1206
R403 1A310 RES SM W4 1% 10K 1206
R404 1A310 RES SM W4 1% 10K 1206
R405 1A310 RES SM W4 1% 10K 1206
R406 1A310 RES SM W4 1% 10K 1206
R407 1A310 RES SM W4 1% 10K 1206
R408 1A310 RES SM W4 1% 10K 1206
R409 1A310 RES SM W4 1% 10K 1206
R410 1A247 RES SM W4 1% 4K7 1206
R411 1A310 RES SM W4 1% 10K 1206
R412 1A310 RES SM W4 1% 10K 1206
R413 1A310 RES SM W4 1% 10K 1206
R414 1A247 RES SM W4 1% 4K7 1206
R415 1A110 RES SM W4 1% 100R 1206
Page 20
L882 Amplifier and PSU Board Parts List Issue 3.0
Designator Part Description
R416 1A110 RES SM W4 1% 100R 1206
R417 1A110 RES SM W4 1% 100R 1206
R418 1A110 RES SM W4 1% 100R 1206
R419 1A110 RES SM W4 1% 100R 1206
R420 1A110 RES SM W4 1% 100R 1206
R421 1A022 RES SM W4 1% 22R 1206
R422 1A022 RES SM W4 1% 22R 1206
R423 1A022 RES SM W4 1% 22R 1206
R424 1A210 RES SM W4 1% 1K0 1206
R425 1A210 RES SM W4 1% 1K0 1206
R426 1A210 RES SM W4 1% 1K0 1206
R427 1A322 RES SM W4 1% 22K 1206
R428 1A247 RES SM W4 1% 4K7 1206
R429 1A247 RES SM W4 1% 4K7 1206
R430 1A510 RES SM W4 1% 1M0 1206
R431 1A215 RES SM W4 1% 1K5 1206
R432 1A218 RES SM W4 1% 1K8 1206
R433 1A233 RES SM W4 1% 3K3 1206
R434 1A322 RES SM W4 1% 22K 1206
R435 1A233 RES SM W4 1% 3K3 1206
R436 1A322 RES SM W4 1% 22K 1206
R437 1A022 RES SM W4 1% 22R 1206
R438 1A115 RES SM W4 1% 150R 1206
R439 1A115 RES SM W4 1% 150R 1206
R440 1A410 RES SM W4 1% 100K 1206
R441 1A133 RES SM W4 1% 330R 1206
R442 1A133 RES SM W4 1% 330R 1206
R443 1A110 RES SM W4 1% 100R 1206
R444 1A110 RES SM W4 1% 100R 1206
R445 1A000 RES SM W4 1% 0R0 1206
R446 1A000 RES SM W4 1% 0R0 1206
R447 1A110 RES SM W4 1% 100R 1206
R448 1A110 RES SM W4 1% 100R 1206
R449 1A110 RES SM W4 1% 100R 1206
R450 1C856 RES CF 2W 5R6 5%
R451 1H010 RES MF W4 1% 10R
R452 1J147 RES 2W MF 5% 470R
R453 1J147 RES 2W MF 5% 470R
R454 1A210 RES SM W4 1% 1K0 1206
R455 1A268 RES SM W4 1% 6K8 1206
RLY100 A207 RELAY G5Z-2A-E 24V
RLY101 A207 RELAY G5Z-2A-E 24V
RLY200 A219 RELAY MAINS DPDT 5V 5A
RV300 6F110 PRES 100R LIN HORIZ
RV400 6F110 PRES 100R LIN HORIZ
SH200 E5402 MAINS EMC SHIELD
SK100 8D418G CAMCON BINDING POST 4WAY GOLD
SK101 8D418G CAMCON BINDING POST 4WAY GOLD
SK102 8K2404 4-WAY AMP CT CONN
SK103 8K7014 FFC 14W 2.54MM VER PTH
SK104 8D225 PHONO SKT 4-WAY EMC GOLD
SK105 8D301 STEREO JACK PCB
SK106 8K2404 4-WAY AMP CT CONN
SK107 8K2404 4-WAY AMP CT CONN
SK200 8K2306 MOLEX MINI FIT HCS 6 WAY
SK201 8D302 MIN JACK DUAL 3.5mm HSJ1002-01-1020
SK202 8Q003 CAGE CLAMP 16A 1 WAY ARC003-236
SK203 8A001 IEC MAINS CONN PCB INS PX
SK204 8K2308 MOLEX MINI FIT HCS 8 WAY
SK205 8K2406 6-WAY AMP CT CONN
SW100 A1008 SW PUSH 2PCO
SW200 A1404 VOLTAGE SELECTOR SLIDE SWITCH
Page 21
L882 Amplifier and PSU Board Parts List Issue 3.0
Designator Part Description
TH200 1T002 THERMISTOR SIEMENS B59008
TR100 4B179 NPN TRANS MP BD179
TR101 4B179 NPN TRANS MP BD179
TR200 4B179 NPN TRANS MP BD179
TR201 4AFMMT497 TRANS LF SS N SM FMMT497
TR202 4AFMMT597 TRANS LF SS P SM FMMT597
TR203 4AFMMT497 TRANS LF SS N SM FMMT497
TR204 4A849B TRANS LF SS N SM BC849B
TR205 4A856B TRANS LF SS P SM BC856B
TR206 4A856B TRANS LF SS P SM BC856B
TR300 4AFMMT597 TRANS LF SS P SM FMMT597
TR301 4AFMMT597 TRANS LF SS P SM FMMT597
TR302 4AFMMT597 TRANS LF SS P SM FMMT597
TR303 4AFMMT597 TRANS LF SS P SM FMMT597
TR304 4AFMMT597 TRANS LF SS P SM FMMT597
TR305 4AFMMT597 TRANS LF SS P SM FMMT597
TR306 4AFMMT597 TRANS LF SS P SM FMMT597
TR307 4AFMMT597 TRANS LF SS P SM FMMT597
TR308 4AFMMT597 TRANS LF SS P SM FMMT597
TR309 4AFMMT497 TRANS LF SS N SM FMMT497
TR310 4AFMMT497 TRANS LF SS N SM FMMT497
TR311 4AFMMT497 TRANS LF SS N SM FMMT497
TR312 4AFMMT497 TRANS LF SS N SM FMMT497
TR313 4AFMMT497 TRANS LF SS N SM FMMT497
TR314 4AFMMT497 TRANS LF SS N SM FMMT497
TR315 4AFMMT497 TRANS LF SS N SM FMMT497
TR316 4AFMMT497 TRANS LF SS N SM FMMT497
TR317 4AFMMT497 TRANS LF SS N SM FMMT497
TR318 4CSAP15N TRANS POWER NPN SAP15N
TR319 4CSAP15P TRANS POWER PNP SAP15P
TR320 4AFMMT497 TRANS LF SS N SM FMMT497
TR321 4AFMMT597 TRANS LF SS P SM FMMT597
TR322 4AFMMT497 TRANS LF SS N SM FMMT497
TR400 4AFMMT597 TRANS LF SS P SM FMMT597
TR401 4AFMMT597 TRANS LF SS P SM FMMT597
TR402 4AFMMT597 TRANS LF SS P SM FMMT597
TR403 4AFMMT597 TRANS LF SS P SM FMMT597
TR404 4AFMMT597 TRANS LF SS P SM FMMT597
TR405 4AFMMT597 TRANS LF SS P SM FMMT597
TR406 4AFMMT597 TRANS LF SS P SM FMMT597
TR407 4AFMMT597 TRANS LF SS P SM FMMT597
TR408 4AFMMT597 TRANS LF SS P SM FMMT597
TR409 4AFMMT497 TRANS LF SS N SM FMMT497
TR410 4AFMMT497 TRANS LF SS N SM FMMT497
TR411 4AFMMT497 TRANS LF SS N SM FMMT497
TR412 4AFMMT497 TRANS LF SS N SM FMMT497
TR413 4AFMMT497 TRANS LF SS N SM FMMT497
TR414 4AFMMT497 TRANS LF SS N SM FMMT497
TR415 4AFMMT497 TRANS LF SS N SM FMMT497
TR416 4AFMMT497 TRANS LF SS N SM FMMT497
TR417 4AFMMT497 TRANS LF SS N SM FMMT497
TR418 4CSAP15N TRANS POWER NPN SAP15N
TR419 4CSAP15P TRANS POWER PNP SAP15P
TR420 4AFMMT497 TRANS LF SS N SM FMMT497
TR421 4AFMMT597 TRANS LF SS P SM FMMT597
TR422 4AFMMT497 TRANS LF SS N SM FMMT497
TX200 7A9301 TRANSFORMER 3VA 9V+9V TYPE 9301
Page 22
87654321
D
C
FROM PREAMP
B
SK102
1
2
3
4
AMPCT4
0V_SIG
SK103
1
2
3
4
5
6
7
8
9
10
11
12
13
14
FFC 14W 2.54MM VER
8K7014
L882C3
SW100A
2PCO
2
PL100
2
C100
1N0 SM
PL101
2
5
L882C3_4.1.SCH
INPUT
0V_SIG
0V_HF
VPOS
VNEG
L882C4
L882C4_4.1.SCH
INPUT
0V_SIG
0V_HF
VPOS
VNEG
3
1
SK104B
TP100
0V_SIG
PHONO4G
1
6
TP103
F
N
TP104
TP105
TP106
VIPROT
DCPROT
OUTPUT0V_LS
VIPROT
DCPROT
OUTPUT0V_LS
TP107
TP108
TP101
TP102
TP109
VIPROT_L
DCPROT_L
LS L
VIPROT_R
DCPROT_R
LS R
TP110
TP117
L SIG
R SIG
0V_D
0V PSU
STANDBY
VIPROT_L
VIPROT_R
0V_TRIG
DCPROT_L
DCPROT_R
LS L
0V_LS_L
LS R
LS L
TP111 TP113 TP115
0V_LS_L
LS R
TP112 TP114 TP116
0V LS R
L882C2
L882C2_4.1.SCH
0V_D +5V(D)
0V_PSU
PWRON
VIPROT_R VIPROT_uC
DCPROT_L
DCPROT_R
SK106
1
2
3
4
AMPCT4
4
5
SK105
HPSKT
RLY100A
RLY G5Z-2A-E
RLY100B
RLY G5Z-2A-E
2
3
1
6
7
THPROT_uCVIPROT_L
AC_PRES0V_TRIG
DCPROT_uC
TP118
TP120
SK100A
Top+
Top-
CAMCON_G
SK101A
Top+
Top-
CAMCON_G
VPOS
VNEG
RC5 IN
TRG IN
TP119
R105
100R 1W CF
L SIG
0V_SIG
0V_LS_L
0V_HF_L
+49V
-49V +5V D
R SIG
0V_SIG
0V_LS_R
0V_HF_R
+49V
-49V
1
1
SK104A
F
EMC
N
PHONO4G
0V_SIG
SW100B
2PCO
4
INTEGRATED / PRE-POWER
MODE SELECT SWITCH
+5V D
R100
+49V
10R MF
STANDBY
SPKR1 ON
SPKR2 ON
THERMPROT
VIPROT
DCPROT
AC PRESENT
TRIGGER
REMOTE
0V_D
+49V
-49V
THERMPROT
VIPROT
AC PRESENT
DCPROT
REMOTE
TRIGGER
R103
330R 1W CF
R104
330R 1W CF
R106
100R 1W CF
RLY101A
RLY G5Z-2A-E
RLY101B
RLY G5Z-2A-E
SK107
1
2
3
4
AMPCT4
SK100B
Bot+
Bot-
CAMCON_G
SK101B
Bot+
Bot-
CAMCON_G
D100
1N4003F
TR100
BD179
0V_TRIG
0V_D
RLY100C
RLY G5Z-2A-E
R107
220R SM
TR101
BD179
34
5 6
TP121
1 2
SP100
STAR_8
RLY101C
RLY G5Z-2A-E
R101
100R SM
R102
100R SM
R108
220R SM
78
D101
1N4003F
PCB
L882PB_4
EL
EARTH LEAD
EARTH LEAD
PCB
8M101
+49V
0V_SIG
0V_HF_R
0V_LS_R
0V_LS_L0V_HF_L
0V_PSU
SPKR1 ON
SPKR2 ON
0V_D
D
C
B
A
1 2 3 4 5 6 7 8
DRAWING TITLE
A85 amplifier and PSU - top sheet
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
Notes:
Filename
L882C1 4.1.PRJ
Circuit Diagram
02_E062 JBR 20/3/02 LDO REG FITTED TO IC201 4.1
02_E035 JBR 4/2/2002 FUSE VALUES UPRATED TO T4A 4.0
ECO No. DESCRIPTION OF CHANGE
Date Printed
INITIALS
20-Mar-2002
DATE
Drawn by:
J Reckless
1 4Sheet of
DRAWING NO.
L882C1
ISSUE
A
Page 23
87654321
NEUTRAL
SK204
4
8
3
7
2
D
SK203
IEC3 NO RIVETS
SW200B
VOL SEL SLIDE
SW200A
VOL SEL SLIDE
F200
T4A
F201
T4A
SH200
EMCMAINS
BC200
TOOLING4.1
EMC Shield
G een
SK202
CAGECLAMP1
1
C205
3N3 MAINS
TP206
N E L
TP200
TP207
EARTH
C234
220N X2 CLASS
R231
1M5 VR25
LNE
C206
3N3 MAINS
LIVENEUTRAL
LIVE
NEUTRAL
LIVE
6
1 5
MOLEXPWR8
RLY200A
DPDT5V
C207
3N3 MAINS
RLY200B
DPDT5V
C208
3N3 MAINS
MAINS WIRING AND AUXILIARY SUPPLY
TP202
TP201
TP210
TP203
NF
VR200
VDR 115V
NF
VR201
VDR 115V
TX200
1 0V
115V
2
3
115V
4
TX 3VA 9301
HS200
+
C227
3300u 25V
TO220HS08REG
IC201
L4940V5
I
Vin
G
C225
100N CD
GND
Vout
+5V_D
O
TP205
HS
C226
100N CD
+5V(D)
+
C228
1000u 10V
0V D
9VRMS
5
9V
0V
6
7
9V
0V
8
F202
T750mA SM
C224
100N CD
D200
1N4003F
D201
1N4003F
TP204
D202
1N4003F
D203
1N4003F
D
0V_D
+5V_D
9VRMS
R219
1K8 SM
C
B
A
STANDBY RELAY CONTROL
PWRON
+5V_D
TH200
PTH90DEG
R205
1K0 SM
R213
4K7 SM
R214
4K7 SM
IC202E
74HC14D
MICROPROCESSOR SIGNALS INTERFACE
IC202F
74HC14D
C219
10N SM
SK200
3
2
1
MOLEXPWR6
SK201A
JACK3.5X2
MODULATED RC5
REMOTE CONTROL INPUT
6
5
4
TP211
Near to PCB
R226
470R SM
3
R227
1K0 SM
~
BR200
1
BRGBU8D
+
~
-
4
TRG IN
R228
100K SM
DZ204
4V7 350MW SM
RC5 IN
TR204
IC202G
74HC14D
C214
10N SM
0V_D
BC849B
D206
BAS16W SM
C201
100N SM
1 2
3 4
C215
10N SM
0V_D
IC202A
74HC14D
IC202B
74HC14D
C202
100N SM
+
C229
22U EL
0V_D
+49V
TP208
+
C209
10,000u 63V
2
+
C210
10,000u 63V
POWER AMP SUPPLY
C211
100N PC
C212
100N PC
0V_PSU
0V_PSU
TP209
VPOS
VNEG
SK205
1
2
3
4
5
6
AMPCT6
-49V
R223
10K SM
R229
100K SM
C231
1N0 SM
+5V_D
84
C200C
LM393A SM
C232
100N SM
+
C233
10U EL
VIPROT_L
VIPROT_R
CARRIER FILTER AND DEMODULATOR
L200
C200
27mH
680P PP
R208
IC200B
10K SM
7
LM393A SM
5
6
R209
10K SM
R224
1K8 SM
R230
1K5 SM
R225
1K8 SM
IC200A
2
3
LM393A SM
C230
10N SM
1
R222
10K SM
R211
10K SM
14
7
R201
1K0 SM
R202
1K0 SM
0V_TRIG
+49V
DCPROT_L
DCPROT_R
TR201
FMMT497
R218
10K SM
DZ207
15V 350MW SM
+
C223
10U EL
0V TRIG
DRAWING TITLE
A85 amplifier - power supply and microcontroller interface
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
+5V_D
C235
1N0 SM
TR200
BD179
TP212
R210
10K SM
CAMCON_G
SK101C
CHASS
R217
10R SM
+
C222
10U EL
R212
4K7 SM
RLY200C
DPDT5V
R200
1K0 SM
TR203
FMMT497
D205
BAS16W SM C213
TR202
FMMT597
10N SM
SK201B
JACK3.5X2
TRIGGER OUTPUT
APPROX 13.5VDC
60mA MAX CURRENT
Far from PCB
0V_TRIG
0V_D
1 2 3 4 5 6 7 8
R203
1K0 SM
R204
1K0 SM
Notes:
Filename
L882C2_4.1.SCH
0V_D
Circuit Diagram
C216
10N SM
C217
10N SM
IC202C
5 6
74HC14D
IC202D
74HC14D
R215
4K7 SM
R216
89
4K7 SM
C221
10N SM
02_E062 JBR 20/3/02 LDO REG FITTED TO IC201 4.1
02_E035 JBR 4/2/2002 FUSE VALUES UPRATED TO T4A 4.0
ECO No. DESCRIPTION OF CHANGE
INITIALS
Date Printed
20-Mar-2002
1011
+5V_D
0V_D
+5V_D
0V_D
1213
TR205
BC856B
R206
1K0 SM
TR206
BC856B
R207
1K0 SM
R221
10R SM
DATE
R220
10R SM
C218
10N SM
C220
100N SM
Drawn by:
J Reckless
AC PRES
THPROT_uC
C203
100N SM
C204
100N SM
VIPROT_uC
DCPROT_uC
2 4Sheet of
DRAWING NO.
L882C2
C
B
A
ISSUE
Page 24
87654321
D
R315
TR300
FMMT597
C310
100N SM
C314
100N SM
TR314
FMMT497
100R SM
PNP CURRENT MIRROR
TR311
FMMT497
R328
4K7 SM
TP302
0V_SIG
84
IC300A
3
1
2
TL072CD
TP303
TR303
FMMT597
NPN CURRENT M RROR
R317
100R SM
R300
10K SM
+
C300
DZ300
100U EL
15V 350MW SM
0V_HF
0V_SIG
C
INPUT
0V_SIG
0V_HF
B
NPUT F LTER V TO I AMP
R324
1K0 SM
DZ302
4V7 350MW SM
DZ303
4V7 350MW SM
0V_SIG
C301
100U EL
C309
100N SM
0V_HF
DZ301
15V 350MW SM
+
R309
10K SM
R327
22K SM
0V_SIG
C316
470P PPW
C317
470N PE
IC300B
7
TL072CD
0V_SIG
TP304
R322
22R SM
R337
22R SM
R319
100R SM
R333
3K3 SM
DC SERVO
R330
6
1M0 SM
5
0V_SIG
R331
1K5 SM
R332
1K8 SM
R335
3K3 SM
R320
100R SM
C307
100P SM
TR322
FMMT497
C311
100N PC
C308
100P SM
R316
100R SM
TR301
FMMT597
TR321
FMMT597
R355
6K8 SM
R354
1K0 SM
TR320
FMMT497
TR315
FMMT497
R318
100R SM
TR309
FMMT497
R338
150R SM
BOOTSTRAP
+
C302
100U EL 100V
R352
470R 2W MF 5%
470R 2W MF 5%
R353
+
C318
10U EL
+
C306
100U EL 100V
BOOTSTRAP
R339
150R SM
TR306
FMMT597
PRE DRIVER
TR310
FMMT497
R321
22R SM
C312
10N SM
R323
22R SM
TR307
FMMT597
PRE DRIVER
ADJ BIAS
RV300
100R PSET
D300
BAS16W SM
OUTPUT STAGE
TR318
SAP15N
TP305
R325
1K0 SM
R340
100K SM
R326
1K0 SM
TP306
TR319
SAP15P
OUTPUT STAGE
PL300
1
2
MEASURE
BIAS
(SET TO 16mV)
R341
330R SM
R342
330R SM
R343
100R SM
R344
100R SM
V-I PROTECTION
R334
22K SM
R347
100R SM
R345
0R0 SM
+
C303
100U EL
+
C304
100U EL
R346
0R0 SM
R348
100R SM
R336
22K SM
V-I PROTECTION
D301
BAS16W SM
TR312
FMMT497
TR304
FMMT597
D302
BAS16W SM
D303
1N4003F
DC OFFSET SIGNAL
TO MICRO
D304
1N4003F
R349
100R SM
DCPROT
TP308
DZ306
4V7 350MW SM
0V_HF
TR305
FMMT597
R302
10K SM
R310
4K7 SM
C315
100N SM
R301
10K SM
R329
4K7 SM
TR313
FMMT497
R303
10K SM
R304
10K SM
TR316
FMMT497
TR308
FMMT597
R311
10K SM
R312
10K SM
TR302
FMMT597
R305
10K SM
R306
10K SM
0V_HF
DC OFFSET
DETECTION
R307
10K SM
R313
10K SM
TR317
FMMT497
VI PROTECT
SIGNAL TO MICRO
TP307
+
C305
10U EL
R308
22K SM
C320
100U NP
VIPROT
DZ305
4V7 350MW SM
R351
10R MF
L300
2U2H LAC SMALL
R350
5R6 2W CF
ZOBEL NETWORK
C319
100N PE
0V_HF 0V_LS
R314
10K SM
C313
100N SM
VPOS
OUTPUT
0V LS
0V_HF
VNEG
D
C
B
A
A
DRAWING TITLE
A85 amplifier - power output stage left
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
1 2 3 4 5 6 7 8
Notes:
Filename
L882C3_4.1.SCH
Circuit Diagram
02_E062 JBR 20/3/02 LDO REG FITTED TO IC201 4.1
02_E035 JBR 4/2/2002 FUSE VALUES UPRATED TO T4A 4.0
ECO No. DESCRIPTION OF CHANGE
Date Printed
INITIALS
20-Mar-2002
DATE
Drawn by:
J Reckless
3 4Sheet of
DRAWING NO.
L882C3
ISSUE
Page 25
87654321
D
R415
TR400
FMMT597
C410
100N SM
C414
100N SM
TR414
FMMT497
100R SM
PNP CURRENT MIRROR
TR411
FMMT497
R428
4K7 SM
TP402
0V_SIG
84
IC400A
3
1
2
TL072CD
TP403
TR403
FMMT597
NPN CURRENT M RROR
R417
100R SM
R400
10K SM
+
C400
DZ400
100U EL
15V 350MW SM
0V_HF
0V_SIG
C
INPUT
0V_SIG
0V_HF
B
NPUT F LTER V TO I AMP
R424
1K0 SM
DZ402
4V7 350MW SM
DZ403
4V7 350MW SM
0V_SIG
C401
100U EL
C409
100N SM
0V_HF
DZ401
15V 350MW SM
+
R409
10K SM
R427
22K SM
C416
470P PPW C411
0V_SIG
C417
470N PE
IC400B
7
TL072CD
0V_SIG
TP404
R422
22R SM
R437
22R SM
R419
100R SM
R433
3K3 SM
DC SERVO
R430
6
1M0 SM
5
0V_SIG
R431
1K5 SM
R432
1K8 SM
R435
3K3 SM
R420
100R SM
C407
100P SM
TR422
FMMT497
100N PC
C408
100P SM
R416
100R SM
TR401
FMMT597
TR421
FMMT597
R455
6K8 SM
R454
1K0 SM
TR420
FMMT497
TR415
FMMT497
R418
100R SM
TR409
FMMT497
R438
150R SM
BOOTSTRAP
+
C402
100U EL 100V
R452
470R 2W MF 5%
470R 2W MF 5%
R453
+
C418
10U EL
+
C406
100U EL 100V
BOOTSTRAP
R439
150R SM
TR406
FMMT597
PRE DRIVER
TR410
FMMT497
R421
22R SM
C412
10N SM
R423
22R SM
TR407
FMMT597
PRE DRIVER
ADJ BIAS
RV400
100R PSET
D400
BAS16W SM
OUTPUT STAGE
TR418
SAP15N
TP405
R425
1K0 SM
R440
100K SM
R426
1K0 SM
TP406
TR419
SAP15P
OUTPUT STAGE
PL400
1
2
MEASURE
BIAS
(SET TO 16 mV)
R441
330R SM
R442
330R SM
R443
100R SM
R444
100R SM
V-I PROTECTION
R434
22K SM
R447
100R SM
R445
0R0 SM
+
C403
100U EL
+
C404
100U EL
R446
0R0 SM
R448
100R SM
R436
22K SM
V-I PROTECTION
D401
BAS16W SM
TR412
FMMT497
TR404
FMMT597
D402
BAS16W SM
D403
1N4003F
DC OFFSET SIGNAL
TO MICRO
D404
1N4003F
R449
100R SM
DCPROT
TP408
DZ406
4V7 350MW SM
0V_HF
TR405
FMMT597
R402
10K SM
R410
4K7 SM
C415
100N SM
R401
10K SM
R429
4K7 SM
TR413
FMMT497
R403
10K SM
R404
10K SM
TR416
FMMT497
TR408
FMMT597
R411
10K SM
R412
10K SM
TR402
FMMT597
R405
10K SM
R406
10K SM
0V_HF
DC OFFSET
DETECTION
R407
10K SM
R413
10K SM
TR417
FMMT497
VI PROTECT
SIGNAL TO MICRO
TP407
+
C405
10U EL
R408
22K SM
C420
100U NP
VIPROT
DZ405
4V7 350MW SM
R451
10R MF
L400
2U2H LAC SMALL
R450
5R6 2W CF
ZOBEL NETWORK
C419
100N PE
0V_HF 0V_LS
R414
10K SM
C413
100N SM
VPOS
OUTPUT
0V LS
0V_HF
VNEG
D
C
B
A
A
DRAWING TITLE
A85 amplifier - power output stage right
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
1 2 3 4 5 6 7 8
Notes:
Filename
L882C4_4.1.SCH
Circuit Diagram
02_E062 JBR 20/3/02 LDO REG FITTED TO IC201 4.1
02_E035 JBR 4/2/2002 FUSE VALUES UPRATED TO T4A 4.0
ECO No. DESCRIPTION OF CHANGE
Date Printed
INITIALS
20-Mar-2002
DATE
Drawn by:
J Reckless
4 4Sheet of
DRAWING NO.
L882C4
ISSUE
Page 26
Display
Board
L928
Contents
!
Component overlay
!
Parts list
!
Circuit diagrams
Page 27
CAM Products 2000(TM): L928PB B.GTO
Page 28
L928 Display Board Parts List Issue B.3
Designator Part Description
C1 2C018 MLC 18P 50V X7R 10% SM
C2 2C018 MLC 18P 50V X7R 10% SM
C3 2C410 MLC 100N 50V X7R 10% SM
C4 2C410 MLC 100N 50V X7R 10% SM
C5 2C410 MLC 100N 50V X7R 10% SM
C6 2C410 MLC 100N 50V X7R 10% SM
C7 2C410 MLC 100N 50V X7R 10% SM
C8 2C410 MLC 100N 50V X7R 10% SM
C9 2C410 MLC 100N 50V X7R 10% SM
C10 2C410 MLC 100N 50V X7R 10% SM
C11 2M610 ELST 10U 50V SM
C12 2C410 MLC 100N 50V X7R 10% SM
C13 2C410 MLC 100N 50V X7R 10% SM
C14 2M610 ELST 10U 50V SM
C15 2C410 MLC 100N 50V X7R 10% SM
C16 2C410 MLC 100N 50V X7R 10% SM
C17 2C410 MLC 100N 50V X7R 10% SM
C25 2C410 MLC 100N 50V X7R 10% SM
C26 2M610 ELST 10U 50V SM
C28 2M610 ELST 10U 50V SM
C29 2M710 ELST 100U 25V SM
C31 2C010A MLC 10P 50V NPO 10% SM
C32 2C010A MLC 10P 50V NPO 10% SM
C33 2N722 ELST 220U 16V
C34 2N722 ELST 220U 16V
C37 2C210 MLC 1N0 50V X7R 10% SM
C38 2C210 MLC 1N0 50V X7R 10% SM
C39 2C210 MLC 1N0 50V X7R 10% SM
C40 2C210 MLC 1N0 50V X7R 10% SM
C41 2C210 MLC 1N0 50V X7R 10% SM
C43 2C210 MLC 1N0 50V X7R 10% SM
C44 2C210 MLC 1N0 50V X7R 10% SM
C45 2C210 MLC 1N0 50V X7R 10% SM
C46 2C210 MLC 1N0 50V X7R 10% SM
C47 2C210 MLC 1N0 50V X7R 10% SM
C48 2C210 MLC 1N0 50V X7R 10% SM
C49 2C210 MLC 1N0 50V X7R 10% SM
C50 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C51 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C52 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C53 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C54 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C55 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C60 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C61 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C62 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
C63 2W110X4 CAP PACK NPO 0612 4X100P 50V 5%
D1 3C13304 ZENER 33V BZX55C33V
D2 3AS16W DIODE SS SM BAS16W
D3 3AS16W DIODE SS SM BAS16W
DC1 E916PM DISPLAY CRADLE E916PM
DC2 E916PM DISPLAY CRADLE E916PM
DISP1 B1013 MN12818A VFD ITRON
IC1 5H3048 H8/3048 128K FLASH MICROCONTROLLER
IC2 5H1233A IC MICRO RESET DS1233 SM
IC5 5G2402 IC CMOS EPROM 24C02 SM
IC6 5M393AD IC COMPARATOR SM DUAL LM393A
IC7 5M393AD IC COMPARATOR SM DUAL LM393A
IC8 5M393AD IC COMPARATOR SM DUAL LM393A
IC11 5M8532 DUAL OUTPUT SINGLE SUPPLY AMP AD8532
LED1 3D001 LED GREEN 5MM
LED2 3D001 LED GREEN 5MM
Page 29
L928 Display Board Parts List Issue B.3
Designator Part Description
LED3 3D001 LED GREEN 5MM
LED4 3D001 LED GREEN 5MM
LED5 3D001 LED GREEN 5MM
LED6 3D001 LED GREEN 5MM
LED7 3D001 LED GREEN 5MM
LED8 3D001 LED GREEN 5MM
LED9 3D001 LED GREEN 5MM
LED10 3D001 LED GREEN 5MM
LED11 3D006 LED RED/GREEN 3MM L-93WEGW
Q1 4A847 TRANS LF SS N SM BC847B
Q2 4A847 TRANS LF SS N SM BC847B
Q3 4A847 TRANS LF SS N SM BC847B
Q4 4A847 TRANS LF SS N SM BC847B
Q5 4B179 NPN TRANS MP BD179
R1 1A310 RES SM W4 2% 10K
R2 1A310 RES SM W4 2% 10K
R3 1A310 RES SM W4 2% 10K
R4 1A310 RES SM W4 2% 10K
R5 1A310 RES SM W4 2% 10K
R6 1A310 RES SM W4 2% 10K
R7 1A310 RES SM W4 2% 10K
R8 1A310 RES SM W4 2% 10K
R9 1A310 RES SM W4 2% 10K
R10 1A310 RES SM W4 2% 10K
R11 1A310 RES SM W4 2% 10K
R12 1A310 RES SM W4 2% 10K
R13 1A310 RES SM W4 2% 10K
R14 1A310 RES SM W4 2% 10K
R15 1A310 RES SM W4 2% 10K
R16 1A310 RES SM W4 2% 10K
R17 1A133 RES SM W4 2% 330R
R18 1A133 RES SM W4 2% 330R
R19 1A133 RES SM W4 2% 330R
R20 1A133 RES SM W4 2% 330R
R21 1A133 RES SM W4 2% 330R
R22 1A133 RES SM W4 2% 330R
R23 1A133 RES SM W4 2% 330R
R24 1A133 RES SM W4 2% 330R
R25 1A133 RES SM W4 2% 330R
R26 1A310 RES SM W4 2% 10K
R27 1A310 RES SM W4 2% 10K
R28 1A310 RES SM W4 2% 10K
R29 1A310 RES SM W4 2% 10K
R30 1A310 RES SM W4 2% 10K
R31 1A133 RES SM W4 2% 330R
R32 1A310 RES SM W4 2% 10K
R33 1A133 RES SM W4 2% 330R
R34 1A115 RES SM W4 2% 150R
R35 1A310 RES SM W4 2% 10K
R36 1A310 RES SM W4 2% 10K
R37 1A310 RES SM W4 2% 10K
R38 1A212 RES SM W4 2% 1K2
R39 1A222 RES SM W4 2% 2K2
R40 1A247 RES SM W4 2% 4K7
R41 1A410 RES SM W4 2% 100K
R42 1A410 RES SM W4 2% 100K
R43 1A410 RES SM W4 2% 100K
R44 1A410 RES SM W4 2% 100K
R45 1A310 RES SM W4 2% 10K
R46 1A212 RES SM W4 2% 1K2
R47 1A247 RES SM W4 2% 4K7
R48 1A000 RES SM W4 2% 0R0
Page 30
L928 Display Board Parts List Issue B.3
Designator Part Description
R49 1A310 RES SM W4 2% 10K
R50 1A310 RES SM W4 2% 10K
R51 1A110 RES SM W4 1% 100R 1206
R52 1A110 RES SM W4 1% 100R 1206
R53 1A110 RES SM W4 1% 100R 1206
R54 1H233 RES MF W4 1% 3K3
R55 1A310 RES SM W4 2% 10K
R56 1A310 RES SM W4 2% 10K
R57 1A310 RES SM W4 2% 10K
R58 1A000 RES SM W4 2% 0R0
R59 1A000 RES SM W4 2% 0R0
R64 1A110 RES SM W4 1% 100R 1206
R65 1A110 RES SM W4 1% 100R 1206
R66 1A110 RES SM W4 1% 100R 1206
R67 1A110 RES SM W4 1% 100R 1206
R68 1A310 RES SM W4 2% 10K
R69 1A822 RES SM W4 1% 2R2 1206
R70 1A822 RES SM W4 1% 2R2 1206
R71 1A822 RES SM W4 1% 2R2 1206
R72 1A822 RES SM W4 1% 2R2 1206
R73 1A310 RES SM W4 2% 10K
R74 1A310 RES SM W4 2% 10K
R75 1A310 RES SM W4 2% 10K
R76 1A310 RES SM W4 2% 10K
RX1 B2107 REMOTE RX PIC-26043TM2 38KHZ
SK1 8K7014A FFC 14W 2.54MM HOR PTH
SK2 8K2005 5-WAY AMP CT CONN
SK3 8K8022A 22-WAY FFC CONN HORIZ 1MM PTH
SK4 8K6315 14 WAY DIL HEADER HORIZ
SP1 F195 LED SPACER
SP2 F195 LED SPACER
SP3 F195 LED SPACER
SP4 F195 LED SPACER
SP5 F195 LED SPACER
SP6 F195 LED SPACER
SP7 F195 LED SPACER
SP8 F195 LED SPACER
SP9 F195 LED SPACER
SP10 F195 LED SPACER
SP101 F163 STICKY PAD S/A 10 X 15mm
SP102 F163 STICKY PAD S/A 10 X 15mm
SP103 E822AP IR RX SUPPORT PAD
SP E822AP IR RX SUPPORT PAD
SW1 A1505 TACT SWITCH SM SDTM-610-NTR
SW2 A1505 TACT SWITCH SM SDTM-610-NTR
SW3 A1505 TACT SWITCH SM SDTM-610-NTR
SW4 A1505 TACT SWITCH SM SDTM-610-NTR
SW5 A1505 TACT SWITCH SM SDTM-610-NTR
SW6 A1505 TACT SWITCH SM SDTM-610-NTR
SW7 A1505 TACT SWITCH SM SDTM-610-NTR
SW8 A1505 TACT SWITCH SM SDTM-610-NTR
SW9 A1505 TACT SWITCH SM SDTM-610-NTR
SW10 A1505 TACT SWITCH SM SDTM-610-NTR
SW11 A1505 TACT SWITCH SM SDTM-610-NTR
SW12 A1505 TACT SWITCH SM SDTM-610-NTR
SW13 A1505 TACT SWITCH SM SDTM-610-NTR
SW14 A1505 TACT SWITCH SM SDTM-610-NTR
SW15 A1505 TACT SWITCH SM SDTM-610-NTR
SW16 A1505 TACT SWITCH SM SDTM-610-NTR
SW17 A1505 TACT SWITCH SM SDTM-610-NTR
SW18 A1211 EC16B2414
X1 7X040 XTAL 16MHZ SM GSX49-4
Page 31
A32 FMJ DISPLAY PCB
87654321
D
D
L928CT_B.1
L928CT_2_B.3.SCH
MICRO
C
CHASSIS 1
(BY SK3)
0V_D
C39
1N0 SM
FD_1
FIDUCIAL
FIX7
FIXING HOLE 3.5
FIX1
FIXING HOLE 3.5
FD_2
FIDUCIAL
FIX2
FIXING HOLE 3.5
0V_D 0V_D 0V_D 0V_D
FIX8
FIXING HOLE 3.5
C40
1N0 SM
FIX10
FIXING HOLE 3.5
C41
1N0 SM
FIX9
FIXING HOLE 3.2
FIX3
FIXING HOLE 3.5
FIX5
FIXING HOLE 3.5
C43
1N0 SM
FIX6
FIXING HOLE 3.5
FIX11
FIXING HOLE 3.5
C44
1N0 SM
FIX13
FIXING HOLE 3.5
C
C38
1N0 SM
0V_D
FIX12
FIXING HOLE 3.2
B
CHASSIS 2
(BY SK1)
0V_D
C45
1N0 SM
PCB1
PCB
L928PB_B
C46
1N0 SM
C47
1N0 SM
0V_D0V_D
CHASSIS 3
(BY SK2)
C48
1N0 SM
C49
1N0 SM
0V_D0V_D
C37
1N0 SM
0V_D
B
A
DRAWING TITLE
A32 FMJ AMP DISPLAY PCB
WAF 26/9/01 STICKY PADS RENUMBERED B.3
Circuit Diagram
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
1 2 3 4 5 6 7 8
Notes:
ECO No. DESCRIPTION OF CHANGE
Filename
J:\Released_Documents\Native_format_files\Protel_DDB\L928_B.3.Ddb - Documents\L928CT_1_B.3.PRJ
Date Printed
JBR 10/9/01 PRE PRODUCTION RELEASE B.2
WAF 9/08/01 UPDATED PROTOTYPE
CL INITIAL PROTOTYPE25/04/01 A.0
INITIALS
10-Oct-2001
DATE
Drawn by:
CL
1 2Sheet of
DRAWING NO.
A
B.0
ISSUE
L928CT1
Page 32
87654321
SP7
LED
SPACER
PHONO/
AV DVD CD TUNER VCR
Q1
BC847B
D
R29
10K SM R30
R33
330R SM
R34
150R SM
Q2
BC847B
10K SM
R1
10K SM
SW6
TACTSW A1505
R2
10K SM
SW12
TACTSW A1505
R3
10K SM
SW11
TACTSW A1505
R4
10K SM
SW8
TACTSW A1505
R5
10K SM
SW7
TACTSW A1505
R6
10K SM
SW13
TACTSW A1505
R7
10K SM
SW14
TACTSW A1505
R8
10K SM
SW15
TACTSW A1505
POWER SP1SP2TONE DOWN UP ENTERMODE RECORD SELECT
R68
10K SM
SW17
TACTSW A1505
R9
10K SM
SW16
TACTSW A1505
R10
10K SM
SW1
TACTSW A1505
R11
10K SM
SW4
TACTSW A1505
R12
10K SM
SW2
TACTSW A1505
AUX TAPE
R13
10K SM
SW5
TACTSW A1505
R14
10K SM
SW3
TACTSW A1505
R15
10K SM
SW10
TACTSW A1505
R16
10K SM
SW9
TACTSW A1505
0V_D
IND12
LED11
IND11
BUT11
BUT2
BUT3
BUT4
IC7B
BUT13
BUT6
BUT7
BUT8
BUT17
BUT9
BUT12
BUT14
BUT1
BUT10
BUT5
BUT15
BUT16
SPACER F195
R17
330R SM
Q_65 Q_66 Q_67 Q_68 Q_69 Q_70 Q_71 Q_72 Q_73 Q_74
LED7
IND10
LED GREEN
SP8
LED
SPACER
SPACER F195
R18
330R SM
LED8
IND2
LED GREEN
SP6
LED
SPACER
SPACER F195
R19
330R SM
LED6
IND8
LED GREEN
SP3
LED
SPACER
SPACER F195
R20
330R SM
IND1
LED GREEN
LED3
LED GREEN
SP10
LED
SPACER
SPACER F195
R21
330R SM
LED10
IND5
LED GREEN
SP9
LED
SPACER
SPACER F195
R22
330R SM
LED9
IND6
SP1
LED
SPACER F195
R25
330R SM
IND9
LED GREEN
SPACER
LED1
LED GREEN
SP4
LED
SPACER
SPACER F195
R24
330R SM
LED4
IND4
SP2
LED
SPACER
SPACER F195
R23
330R SM
IND3
LED GREEN
SP5
SPACER F195
LED2
LED GREEN
LED
SPACER
+5V
R31
330R SM
LED5
IND7
D
5
R
LED RED/GRN 3MM
G
6
LM393A SM
0V_D
7
+5V
0V_D
LEFTAUDIO
10U EL SM
C11
+
R41
100K SM
+5V
R43
100K SM
3
Q 35
IC7A
LM393A SM
1
+5V
R49
10K SM
R480R0 SM
TRANSMIT
RECEIVE
R50
10K SM
Q_34
SAMHOLD
+5V
R37
10K SM
2V7
1
5
6
IC6A
IC6B
LM393A SM
0V5
2
3
7
SAMDATA
0V_D
R40
4K7 SM
R38
1K2 SM
2
Q_53
R42
100K SM
C
R44
100K SM
Q_47
+5V
C9
LM393A SM
0V_D
100N SM
Programming adaptor
PR_GND
PR TXD
PR MD
PR RESET
+5V
Q_39
0V_D
C7
100N SM
0V_D
TRANSMIT
RESPIN
SAMHOLD
Q_37
X1
16MHZ SM
Q_38
+5V
IC2
3
2
4
1
DS1233 SM
Vcc
Res
Gnd
Gnd
0V_D
To preamp board
SK3
22
Q_1
21
Q_2
20
Q_3
19
Q_4
18
Q_5
17
Q_6
16
Q_7
15
Q_8
14
Q_9
13
12
Q_10
11
10
Q_11
9
Q_12
8
Q 117
7
Q_14
6
Q 118
5
Q_15
4
Q_119
3
Q_16
2
Q_120
1
Q_17
FFC 22W 1MM HOR
SK4
F1CLOCK
F2CLOCK
PHASEA
PHASEB
SEL8
SEL9
MUTE
TONE
ACPRESENT
IRIN
DCPROT
VIPROT
Q_55
RECEIVE
VPROG
PB0
PR_VCC
PR RXD
PR VPP
PR PMODE
12
34
56
78
910
1112
+5V
+
C14
10U EL SM
0V_D
+5V
Q_56
C4
100N SM
Q 86
Q 87
Q 88
Q 89
Q 90
Q_91
0V_D
C50B 100PX4 SM
C50D 100PX4 SM
C51B 100PX4 SM
C51D 100PX4 SM
C52B 100PX4 SM
C52D 100PX4 SM
C53B 100PX4 SM
C53D 100PX4 SM
C54B 100PX4 SM
C54D 100PX4 SM
C55B 100PX4 SM
C55D 100PX4 SM
AVcc
MD2
MD1
MD0
P6 4/RD
P6 3/AS
Vcc
XTAL
EXTAL
Vss
NM1
RES
STBY
Vss
H8/3048F
Q_98
C3
100N SM
IC1
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
0V_D
0V_D
+5V
C17
+5V
R55
10K SM
Q_51
D3
BAS16W SM
Q 52
B
DISPDAT
DISPCLK
DISPBLK
DISPLAT
C31
10P SM
R64
100R SM
R65
100R SM
R67
100R SM
C32
10P SM
Q_44
Q 46
Q_45
R66
100R SM
Q_42
Q_43
100N SM
PB0
SEL7
SEL6
SEL5
SEL4
SEL3
SEL2
SEL1
VPROG
TRANSMIT
RECEIVE
TONEID
SDATA
SLOAD
SCLK
0V_D
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Vcc
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
Vpp/RESO
Vss
TxD0/P9 0
TxD1/P9 1
RxD0/P9 2
RxD1/P9 3
IRQ4/SCK0/P9 4
IRQ5/SCK1/P9 5
D0/P4 0
D1/P4 1
D2/P4 2
D3/P4 3
Vss
D4/P4 4
D5/P4 5
D6/P4 6
0V_D
100
PA7
D7/P4 726D8/P3 027D9/P3 128D10/P3 229D11/P3 330D12/P3 431D13/P3 532D14/P3 633D15/P3 734Vcc35A0/P1 036A1/P1 137A2/P1 238A3/P1 339A4/P1 440A5/P1 541A6/P1 642A7/P1 743Vss44A8/P2 045A9/P2 146A10/P2 247A11/P2 348A12/P2 449A13/P2 5
99
98
PA6
97
PA5
96
PA4
PA3
95
94
PA2
93
PA1
92
PA0
91
Vss
P8 4/CS0
89
90
P8 3/IRQ3
H8/3048F
87
88
P8 1/IRQ1
P8 2/IRQ2
86
AVss
P8 0/IRQ0
82
83
84
85
P7 5/AN5
P7 6/AN6/DA0
P7 7/AN7/DA1
80
81
P7 3/AN3
P7 4/AN4
79
P7 2/AN2
77
78
P7 0/AN0
P7 1/AN1
P6 2/BACK
76
Vref
P6 6/LWR
P6 5/HWR
CLKOUT
P6 1/BREQ
P6 0/WAIT
P5 3/A19
P5 2/A18
P5 1/A17
P5 0/A16
P2 7/A15
P2 6/A14
0V_D
+5V
R51
100R SM
Q_41
Q_40
+5V
R32
10K SM
5
6WP7
IC5
24C02 SM
SCL
VSS
SDA
VDD
A0
8
C8
100N SM
4
A
C5
100N SM
0V_D
Q 99
Q 100
BUT13
IND10
Q 101
Q 102
BUT11
IND8
Q 103
Q 104
BUT14
IND4
Q 105
Q 106
BUT12
IND9
Q 107
Q 108
BUT10
IND7
Q 109
Q 110
BUT15
IND5
Q_111
Q 112
BUT16
IND6
Q 113
Q 114
IND12
IND11
Q 96
Q 97
IND2
BUT4
BUT5
Q 95
Q 93
Q 94
BUT1
IND1
50
Q 92
BUT3
1A12A23
0V_D
CHASSIS 1
HEADER 7X2HORIZ
R26
10K SM
STANDBY
SP1ON
SP2ON
THERMPROT
RESPIN
SAMTX2
SAMRX2
BUT17
BUT9
BUT8
BUT7
BUT6
BUT2
IND3
0V_D
C50A 100PX4 SM
C50C 100PX4 SM
C51A 100PX4 SM
C51C 100PX4 SM
C52A 100PX4 SM
C52C 100PX4 SM
C53A 100PX4 SM
C53C 100PX4 SM
C54A 100PX4 SM
C54C 100PX4 SM
C55A 100PX4 SM
C55C 100PX4 SM
1314
D2
BAS16W SM
+5V
R35
10K SM
SAMTX2
SAMRX2
C1
18P SM
0V_D
C2
18P SM
DS1233
SEL1
SEL2
SEL3
SEL4
SEL5
SEL6
SEL7
SEL8
SEL9
LEFTAUDIO
MUTE
TONE
TONEID
SDATA
SLOAD
SCLK
Q_115
R72
Q_21 Q_22
R36
10K SM
Q_59
2V7
+5V
R45
10K SM
IC8B
7
LM393A SM
PLACE ONE ON TOP OF
THE OTHER UNDER RX1
C12
100N SM
R70
R71
2R2 SM
2R2 SM
2R2 SM
0V52V7
IC8A
3
2
LM393A SM
R69
2R2 SM
R39
2K2 SM
0V_D
1
0V5
6
5
SAMDATA
SAMBUSY
Q_19
Q_20
+5V
+
C33
220U EL
+
0V_D
(FIT CLOSE TO SK1)
+SUP VFD VDD2
R54
3K3 MF
D1
ZENER 400MW 33V
+5V
R47
4K7 SM
SAMBUSY
R46
1K2 SM
0V_D
Q_54
SP
IR RX
SUPPORT PAD
IR RX SUPPORT PAD
SBX1610-52/PIC-26043TM2
SP103
IR RX
SUPPORT PAD
IR RX SUPPORT PAD
+5V
SK2
1
2
3
4
5
AMPCT5
0V_D
C34
220U EL
Q5
BD179 NPN TO-126
Q_75
+
C26
10U EL SM
DRAWING TITLE
A32 FMJ AMP DISPLAY PCB
23425
2
RX1
O/P
O/P
Case
0V_D
0V_D
+5V
3
+5V
Case
Notes:
IROUT
GND
GND +5V
1
SW18
ALPS_ENCODER
4
5
C60C 100PX4 SM
C60A 100PX4 SM
C61C 100PX4 SM
C61A 100PX4 SM
C62C 100PX4 SM
C62A 100PX4 SM
C63C 100PX4 SM
C63B 100PX4 SM
C63A 100PX4 SM
CHASSIS 2
Q_23
+
C28
10U EL SM
R76
10K SM
C6
100N SM
A
B
C
C13
100N SM
R75
10K SM
+5V
R27
R2810K SM
10K SM
1
2
3
0V_D
C60D 100PX4 SM
C60B 100PX4 SM
C61D 100PX4 SM
C61B 100PX4 SM
C62D 100PX4 SM
C62B 100PX4 SM
C63D 100PX4 SM
84
IC6C
LM393A SM
Circuit Diagram
R73
10K SM
Q3
BC847B
0V_D
Q 58
Q_57
PHASEA
PHASEB
To power amp / PSU
FFC 14W 2.54MM HOR
C10
100N SM
+5V
R74
10K SM
IRIN
Q4
BC847B
SK1
14
13
12
11
10
9
8
7
6
5
4
3
2
1
84
IC7C
LM393A SM
+5V
R56
10K SM
R57
10K SM
0V_D
+5V
0V_D
F1 to F2 = 4Vac 150mA
VDD2 = 40Vdc 20mA
Graphics Display
+5V
17
IRIN
SP101
DOUBLE SIDED
STICKY PAD
10 X 15MM
STICKY PAD DS 10X15MM
SP102
DOUBLE SIDED
STICKY PAD
10 X 15MM
STICKY PAD DS 10X15MM
DC1
DISP1
B1013
F11F12F13SIN4VDD15SOUT6LAT7BLK8CLK9VSS10VSS11VDD212F215F216F2
DISPLAY CRADLE
E916PM
DISPLAY CRADLE E916PM
F1CLOCK
Q_50
F2CLOCK
DC2
DISPLAY CRADLE
E916PM
DISPLAY CRADLE E916PM
R52
Q_79
Q_78
100R SM
R53
100R SM
IC11A
AD8532 SM
3
2
5
6
IC11B
AD8532 SM
Q_82
1
Q_80
7
Q_81
DISPDAT
DISPLAT
Q_49
R58
0R0 SM
R59
0R0 SM
0V_D
DISPCLK
DISPBLK
Q_83
Q_84
Q_85
Q_48
+SUP
Q_121
STANDBY
SP1ON
SP2ON
THERMPROT
VIPROT
DCPROT
ACPRESENT
IRIN
Q_122
Q_123
Q_124
Q_125
Q_126
Q_127
Q_128
Q_129
+5V
Q_64
C15
100N SM
84
IC8C
LM393A SM
C16
100N SM
84
IC11C
AD8532 SM
Q_116
C25
100N SM
+
C29
100U EL SM
0V_D
WAF 26/9/01 STICKY PADS RENUMBERED B.3
JBR 10/9/01 PRE PRODUCTION RELEASE B 2
WAF 9/08/01 UPDATED PROTOTYPE
VFD_VDD2
C
B
A
B.0
A & R Cambridge Ltd.
Pembroke Avenue
0V_D
1 2 3 4 5 6 7 8
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
ECO No. DESCRIPTION OF CHANGE
Filename
J:\Released Documents\Native format files\Protel DDB\L928 B.3.Ddb - Documents\L928CT 2 B 3 SCH
Date Printed
CL 25/04/01 INITIAL PROTOTYPE
INITIALS
10-Oct-2001
DATE
Drawn by:
CL
2 2Sheet of
DRAWING NO.
L928CT2
A.0
ISSUE
Page 33
Preamplifier
Board
L937
Contents
!
Circuit description
!
Component overlay
!
Parts list
!
Circuit diagrams
Page 34
Pre-amplifier circuit description
Refer to L937 circuit diagrams
The A32 preamplifier i s a high-performance, DC coup led
design with microprocessor control of input select, two
independent tape loops, electronic volume control, tone
bypass and electronic tone control.
It features a discrete power supply and low-noise linear
circuitry to obtain very good distortion and noise
performance, suitable for high quality source material such
as CD or DVD-A.
Input switching
Each of the inpu ts has a pa ir of di odes to th e ±15 V rails t o
prevent st atic spikes from ca using damage to th e CMOS
multiplexers. In addition, there is a simple resistorcapacitor filter with a corn er frequency of approximately
340kHz to remove any unwanted high frequency
interference from the signal. This uses high-quality
polypropylene capacitors for best performance.
Z104 and Z105 are the main input select multiplexers,
which are configured in a ‘virtual earth’ unity gain
arrangement with Z115 and Z116. This arrangement is
slightly lower di stortion than th e ‘normal’ one, at th e cost
of a slightly higher noise floor. It is an inverting
configuration, which is restored to correct polarity by the
inverting elect r onic volume cont rol which follows.
Z115B and Z116B are integrating servos, which take out
any DC from the input signal before th e following stages.
The servos are 2-pole, with a passive 2
formed by R180 and C147 (for the left channel) to remove
broadband nois e from the outp ut of the servo a nd improve
speed of response.
Z100 thru Z103 are t he inpu t s elect or s for t h e 2 tape loop s.
These are normal non-inverting selectors which are
buffered before being passed on to the phono sockets.
Z109A output is decoupled by R108 which is included in
the feedback path. Local high frequency feedback occurs
around C108 t o allow th e tape loop output to b e very low
impedance, wh ilst bein g stable in to a capaci tive load s uch
as may be presented by a screened interconnect cable. This
is the same for all t ape outputs.
Z106 is configured as a double pole changeover switch,
used to select the tone controls. The tone controls are
bypassed when not required so that the noise and distortion
can be minimis e d.
Tone control circuit
The tone control circuit is a non-inverting one, using a
gyrated ‘bell’ filter for t he bass and a simple shelving filter
for the treble.
Left channel description
The input is attenuated by 6dB and biased to a voltage of
+2.5V DC b y C111, R113, R112, R110 , R111 and C 110.
This is so the signals fall within the 0 - 5VDC required by
the digital pote ntiometer Z108.
Z111B and its associated components form an active
equivalent of a series resonant LCR circuit. This has an
impedance minimu m of 5.4k˜ at around 80Hz with Q=0 .7
The reason the bass is done as a band-boost filter rather
than a shelving filter is so that you can boost the ‘real’
bass without causing lots of sub-audio loudspeaker cone
nd
pole being
excursion which wastes power and may damage the drive
units.
The digital pots Z108D and Z108A control the bass and
treble respectively. This is done by moving the wiper
connected to the frequency-sensitive impedance between the
non-inverting and inverting terminals of Z112A, effectively
changing the ratio of feedback boost and feed-forward
attenuation of the circuit at the desired frequencies, thus
providing a EQ gain control that is symmetrical on a
logarithmic scale, with the use of a linear pot.
Z112B provides the 6dB of gain necessary to bring the
nominal signa l level back to unity. C116 and C117 remove
the 2.5VDC offset from the ou tput, to preven t clunks when
the tone controls are activated.
Z108 is controlled by a simple 3-wi re serial interface from
the microprocessor. Each of the digital lines has its own
ground return to minimise electromagnetic interference.
They are connected together only at the GND pin of the IC.
Volume control
Z107 is a VSDVC electronic volume control IC. It works, in
conjunction wi th an external op-amp, by var yi ng the feedforward and feedback resistors in an inverting gain
configuration. In this way, it can allow output signal swings
of up to 22Vpp whilst operating from a single +5VDC power
supply. Also, it allows the user the choice of external
circuitry to fine-tune t he performance. Th e gain is controll ed
from the microprocessor via a 3-wire serial interface. The
analogue supply rai l is derived from the local +5 V via R185
and C156 // C157.
Z117 is the output op-amp. Its outputs are decoupled via
R186, R187, C158 and C159 so that it has a low output
impedance but can drive cable capacitance without
oscillation. R186 and R187 are included in the audio
frequency feedback loop to reduce output impedance when
driving ‘difficult’ cables.
RLY100 is a mute relay which shunts the preamp output to
ground. This is to prevent thumps and squeals when the units
is powered up or down.
Power supply
The transformer winding is connected to SK300. The voltage
is rectified and smoothed by D300, D301, D306, D307 and
C300, C310. The unregulated voltage should be around
±27VDC. F300 and F301 are secondary fuses, as the low
power preamp winding would not blow the primary fuses if
short circuited.
The voltage regulators are discrete compound emitter
followers. I will describe the +15V supply as the negative is
essentially an exact mirror image.
Q300 and R300 act as a constant current source, supplying
around 7mA into D310. C302 and C314 reduce ripple and
broadband n oise on th e zener diod e. Q305 and Q306 form a
complementary Darlington NPN transistor which is
configured as an emitter follower, producing the +15VDC at
its output. C303 is to provide bulk charge storage and to
reduce the AC output impedance of the power supply. D302
prevents reverse bias of the supply during
power down.
Z301 is a conventional LM317 type circuit to drop the +15V
rail down to +5V for the tone and volume control circuits.
Star point SP300 explicitly connects the differently named
ground nets tog ether at one point, to minimise hum .
Page 35
Page 36
L937 Preamplifier Board Parts List Issue 1.0
Designator Part Description
C100 2C210 MLC 1N0 50V X7R 10% SM
C101 2D147W WIMA FKP2 470P 63V CAP
C102 2D147W WIMA FKP2 470P 63V CAP
C103 2D147W WIMA FKP2 470P 63V CAP
C104 2C410 MLC 100N 50V X7R 10% SM
C105 2C410 MLC 100N 50V X7R 10% SM
C106 2C410 MLC 100N 50V X7R 10% SM
C107 2C410 MLC 100N 50V X7R 10% SM
C108 2C110 MLC 100P 50V NPO 5% SM
C109 2C110 MLC 100P 50V NPO 5% SM
C110 2N710 ELST 100U 25V
C111 2P610CC ELEC 10U 50V CERAFINE
C112 2K447 PEST 470N 63V 10%
C113 2K447 PEST 470N 63V 10%
C114 2D222W WIMA FKP2 2N2 63V CAP
C115 2C022 MLC 22P 50V NPO 5% SM
C116 2P610CC ELEC 10U 50V CERAFINE
C117 2P610CC ELEC 10U 50V CERAFINE
C118 2C410 MLC 100N 50V X7R 10% SM
C119 2C310 MLC 10N 50V X7R 10% SM
C120 2N610 ELST 10U 50V
C121 2C210 MLC 1N0 50V X7R 10% SM
C122 2D147W WIMA FKP2 470P 63V CAP
C123 2D147W WIMA FKP2 470P 63V CAP
C124 2D147W WIMA FKP2 470P 63V CAP
C125 2C410 MLC 100N 50V X7R 10% SM
C126 2C410 MLC 100N 50V X7R 10% SM
C127 2C410 MLC 100N 50V X7R 10% SM
C128 2C410 MLC 100N 50V X7R 10% SM
C129 2C110 MLC 100P 50V NPO 5% SM
C130 2C110 MLC 100P 50V NPO 5% SM
C131 2N710 ELST 100U 25V
C132 2P610CC ELEC 10U 50V CERAFINE
C133 2K447 PEST 470N 63V 10%
C134 2K447 PEST 470N 63V 10%
C135 2D222W WIMA FKP2 2N2 63V CAP
C136 2C022 MLC 22P 50V NPO 5% SM
C137 2P610CC ELEC 10U 50V CERAFINE
C138 2P610CC ELEC 10U 50V CERAFINE
C139 2C210 MLC 1N0 50V X7R 10% SM
C140 2D147W WIMA FKP2 470P 63V CAP
C141 2D147W WIMA FKP2 470P 63V CAP
C142 2D147W WIMA FKP2 470P 63V CAP
C143 2C410 MLC 100N 50V X7R 10% SM
C144 2C410 MLC 100N 50V X7R 10% SM
C145 2C410 MLC 100N 50V X7R 10% SM
C146 2C410 MLC 100N 50V X7R 10% SM
C147 2K410 PEST 100N 63V 10%
C148 2C022 MLC 22P 50V NPO 5% SM
C149 2C022 MLC 22P 50V NPO 5% SM
C150 2K447 PEST 470N 63V 10%
C151 2K447 PEST 470N 63V 10%
C152 2C410 MLC 100N 50V X7R 10% SM
C153 2C410 MLC 100N 50V X7R 10% SM
C154 2N610 ELST 10U 50V
C155 2C410 MLC 100N 50V X7R 10% SM
C156 2C410 MLC 100N 50V X7R 10% SM
C157 2N710 ELST 100U 25V
C158 2C022 MLC 22P 50V NPO 5% SM
C159 2C022 MLC 22P 50V NPO 5% SM
C160 2C210 MLC 1N0 50V X7R 10% SM
C161 2D147W WIMA FKP2 470P 63V CAP
Page 37
L937 Preamplifier Board Parts List Issue 1.0
Designator Part Description
C162 2D147W WIMA FKP2 470P 63V CAP
C163 2D147W WIMA FKP2 470P 63V CAP
C164 2C210 MLC 1N0 50V X7R 10% SM
C165 2D147W WIMA FKP2 470P 63V CAP
C166 2D147W WIMA FKP2 470P 63V CAP
C167 2K410 PEST 100N 63V 10%
C168 2C410 MLC 100N 50V X7R 10% SM
C169 2C410 MLC 100N 50V X7R 10% SM
C170 2C410 MLC 100N 50V X7R 10% SM
C171 2C410 MLC 100N 50V X7R 10% SM
C172 2C410 MLC 100N 50V X7R 10% SM
C173 2C410 MLC 100N 50V X7R 10% SM
C174 2C410 MLC 100N 50V X7R 10% SM
C175 2C410 MLC 100N 50V X7R 10% SM
C176 2C410 MLC 100N 50V X7R 10% SM
C177 2C410 MLC 100N 50V X7R 10% SM
C178 2C410 MLC 100N 50V X7R 10% SM
C179 2C410 MLC 100N 50V X7R 10% SM
C180 2C410 MLC 100N 50V X7R 10% SM
C181 2C410 MLC 100N 50V X7R 10% SM
C182 2C410 MLC 100N 50V X7R 10% SM
C183 2C410 MLC 100N 50V X7R 10% SM
C184 2C410 MLC 100N 50V X7R 10% SM
C185 2C410 MLC 100N 50V X7R 10% SM
C186 2C410 MLC 100N 50V X7R 10% SM
C187 2N610 ELST 10U 50V
C188 2N610 ELST 10U 50V
C189 2N610 ELST 10U 50V
C190 2N610 ELST 10U 50V
C191 2N610 ELST 10U 50V
C192 2K447 PEST 470N 63V 10%
C193 2K447 PEST 470N 63V 10%
C300 2N810C ELST 1M0 35V
C302 2N722 ELST 220U 16V
C303 2N833 ELST 3M3 25V
C304 2C410 MLC 100N 50V X7R 10% SM
C305 2N610 ELST 10U 50V
C306 2N747 ELST 470U 25V RA
C307 2K447 PEST 470N 63V 10%
C308 2C410 MLC 100N 50V X7R 10% SM
C309 2C410 MLC 100N 50V X7R 10% SM
C310 2N810C ELST 1M0 35V
C312 2N722 ELST 220U 16V
C313 2N833 ELST 3M3 25V
C314 2D210 PPRO 1N0 5% 63V RA
C315 2D210 PPRO 1N0 5% 63V RA
D100 3AV99W DIODE SS SM BAV99W
D101 3AV99W DIODE SS SM BAV99W
D102 3AV99W DIODE SS SM BAV99W
D103 3AV99W DIODE SS SM BAV99W
D104 3AV99W DIODE SS SM BAV99W
D105 3AV99W DIODE SS SM BAV99W
D106 3AV99W DIODE SS SM BAV99W
D107 3AV99W DIODE SS SM BAV99W
D108 3AV99W DIODE SS SM BAV99W
D109 3AV99W DIODE SS SM BAV99W
D110 3AV99W DIODE SS SM BAV99W
D111 3AV99W DIODE SS SM BAV99W
D112 3AV99W DIODE SS SM BAV99W
D113 3AV99W DIODE SS SM BAV99W
D114 3AV99W DIODE SS SM BAV99W
D115 3AV99W DIODE SS SM BAV99W
Page 38
L937 Preamplifier Board Parts List Issue 1.0
Designator Part Description
D116 3AV99W DIODE SS SM BAV99W
D117 3AV99W DIODE SS SM BAV99W
D118 3AV99W DIODE SS SM BAV99W
D119 3AV99W DIODE SS SM BAV99W
D120 3AS16W DIODE SS SM BAS16W
D121 3AV99W DIODE SS SM BAV99W
D122 3AV99W DIODE SS SM BAV99W
D300 3BS1D RECT S1D 1A 200V SM
D301 3BS1D RECT S1D 1A 200V SM
D302 3AS16W DIODE SS SM BAS16W
D304 3AS16W DIODE SS SM BAS16W
D305 3AS16W DIODE SS SM BAS16W
D306 3BS1D RECT S1D 1A 200V SM
D307 3BS1D RECT S1D 1A 200V SM
D308 3AS16W DIODE SS SM BAS16W
D310 3CW315V ZENER 15V OW35 SM SOT23
D311 3CW315V ZENER 15V OW35 SM SOT23
F300 C3751 FUSE R452 T750mA
F301 C3751 FUSE R452 T750mA
PCB1 L937PB_1 PRINTED CIRCUIT BOARD
Q100 4A849B TRANS LF SS N SM BC849B
Q300 4J112 TRANS JFET N J112
Q301 4B5248 TRANS AUDIO DRIVER N 2SC5248
Q303 4J112 TRANS JFET N J112
Q305 4B1964 TRANS AUDIO DRIVER P 2SA1964
Q306 4A846B TRANS LF SS N SM BC846B
Q307 4A856B TRANS LF SS P SM BC856B
R100 1A210 RES SM W4 1% 1K0 1206
R101 1A210 RES SM W4 1% 1K0 1206
R102 1A210 RES SM W4 1% 1K0 1206
R103 1A410 RES SM W4 1% 100K 1206
R104 1A410 RES SM W4 1% 100K 1206
R105 1A410 RES SM W4 1% 100K 1206
R106 1A510 RES SM W4 1% 1M0 1206
R107 1A510 RES SM W4 1% 1M0 1206
R108 1A047 RES SM W4 1% 47R 1206
R109 1A047 RES SM W4 1% 47R 1206
R110 1A222 RES SM W4 1% 2K2 1206
R111 1A222 RES SM W4 1% 2K2 1206
R112 1A322 RES SM W4 1% 22K 1206
R113 1A322 RES SM W4 1% 22K 1206
R114 1A322 RES SM W4 1% 22K 1206
R115 1A227 RES SM W4 1% 2K7 1206
R116 1A227 RES SM W4 1% 2K7 1206
R117 1A256 RES SM W4 1% 5K6 1206
R118 1A322 RES SM W4 1% 22K 1206
R119 1A322 RES SM W4 1% 22K 1206
R120 1A322 RES SM W4 1% 22K 1206
R121 1A322 RES SM W4 1% 22K 1206
R122 1A822 RES SM W4 1% 2R2 1206
R123 1A822 RES SM W4 1% 2R2 1206
R124 1A822 RES SM W4 1% 2R2 1206
R125 1A210 RES SM W4 1% 1K0 1206
R126 1A210 RES SM W4 1% 1K0 1206
R127 1A210 RES SM W4 1% 1K0 1206
R128 1A410 RES SM W4 1% 100K 1206
R129 1A410 RES SM W4 1% 100K 1206
R130 1A410 RES SM W4 1% 100K 1206
R131 1A510 RES SM W4 1% 1M0 1206
R132 1A510 RES SM W4 1% 1M0 1206
R133 1A047 RES SM W4 1% 47R 1206
R134 1A047 RES SM W4 1% 47R 1206
Page 39
L937 Preamplifier Board Parts List Issue 1.0
Designator Part Description
R135 1A222 RES SM W4 1% 2K2 1206
R136 1A222 RES SM W4 1% 2K2 1206
R137 1A322 RES SM W4 1% 22K 1206
R138 1A322 RES SM W4 1% 22K 1206
R139 1A322 RES SM W4 1% 22K 1206
R140 1A227 RES SM W4 1% 2K7 1206
R141 1A227 RES SM W4 1% 2K7 1206
R142 1A256 RES SM W4 1% 5K6 1206
R143 1A322 RES SM W4 1% 22K 1206
R144 1A322 RES SM W4 1% 22K 1206
R145 1A322 RES SM W4 1% 22K 1206
R146 1A322 RES SM W4 1% 22K 1206
R147 1A322 RES SM W4 1% 22K 1206
R148 1A322 RES SM W4 1% 22K 1206
R149 1A322 RES SM W4 1% 22K 1206
R150 1A322 RES SM W4 1% 22K 1206
R151 1A322 RES SM W4 1% 22K 1206
R152 1A322 RES SM W4 1% 22K 1206
R153 1A322 RES SM W4 1% 22K 1206
R154 1A322 RES SM W4 1% 22K 1206
R155 1A322 RES SM W4 1% 22K 1206
R156 1A210 RES SM W4 1% 1K0 1206
R157 1A210 RES SM W4 1% 1K0 1206
R158 1A210 RES SM W4 1% 1K0 1206
R159 1A410 RES SM W4 1% 100K 1206
R160 1A410 RES SM W4 1% 100K 1206
R161 1A410 RES SM W4 1% 100K 1206
R162 1A322 RES SM W4 1% 22K 1206
R163 1A322 RES SM W4 1% 22K 1206
R164 1A322 RES SM W4 1% 22K 1206
R165 1A322 RES SM W4 1% 22K 1206
R166 1A322 RES SM W4 1% 22K 1206
R167 1A322 RES SM W4 1% 22K 1206
R168 1A322 RES SM W4 1% 22K 1206
R169 1A322 RES SM W4 1% 22K 1206
R170 1A322 RES SM W4 1% 22K 1206
R171 1A322 RES SM W4 1% 22K 1206
R172 1A322 RES SM W4 1% 22K 1206
R173 1A322 RES SM W4 1% 22K 1206
R174 1A322 RES SM W4 1% 22K 1206
R175 1A322 RES SM W4 1% 22K 1206
R176 1A322 RES SM W4 1% 22K 1206
R177 1A322 RES SM W4 1% 22K 1206
R178 1A322 RES SM W4 1% 22K 1206
R179 1A322 RES SM W4 1% 22K 1206
R180 1A410 RES SM W4 1% 100K 1206
R182 1A110 RES SM W4 1% 100R 1206
R183 1A510 RES SM W4 1% 1M0 1206
R184 1A510 RES SM W4 1% 1M0 1206
R185 1A022 RES SM W4 1% 22R 1206
R186 1A047 RES SM W4 1% 47R 1206
R187 1A047 RES SM W4 1% 47R 1206
R188 1A310 RES SM W4 1% 10K 1206
R189 1A210 RES SM W4 1% 1K0 1206
R190 1A210 RES SM W4 1% 1K0 1206
R191 1A210 RES SM W4 1% 1K0 1206
R192 1A410 RES SM W4 1% 100K 1206
R193 1A410 RES SM W4 1% 100K 1206
R194 1A410 RES SM W4 1% 100K 1206
R195 1A210 RES SM W4 1% 1K0 1206
R196 1A210 RES SM W4 1% 1K0 1206
R197 1A410 RES SM W4 1% 100K 1206
Page 40
L937 Preamplifier Board Parts List Issue 1.0
Designator Part Description
R198 1A410 RES SM W4 1% 100K 1206
R199 1A410 RES SM W4 1% 100K 1206
R200 1A822 RES SM W4 1% 2R2 1206
R201 1A822 RES SM W4 1% 2R2 1206
R202 1A822 RES SM W4 1% 2R2 1206
R203 1A247 RES SM W4 1% 4K7 1206
R204 1A310 RES SM W4 1% 10K 1206
R300 1A133 RES SM W4 1% 330R 1206
R302 1A212 RES SM W4 1% 1K2 1206
R303 1A147 RES SM W4 1% 470R 1206
R304 1A133 RES SM W4 1% 330R 1206
R307 1A122 RES SM W4 1% 220R 1206
RLY100 A216 RELAY DPDT 5V SM NEC EB2-5NU
SK2 8D225 PHONO SKT 4-WAY EMC GOLD
SK3 8D225 PHONO SKT 4-WAY EMC GOLD
SK4 8D225 PHONO SKT 4-WAY EMC GOLD
SK5 8D225 PHONO SKT 4-WAY EMC GOLD
SK6 8D226 PHONO SKT 2-WAY EMC GOLD
SK100 8K8022B Connector 1mm vertical 22way Molex 52806-2210
SK101 8K8330 30-WAY FFC VERT CONN SM 1MM
SK102 8K2404 4-WAY AMP CT CONN
SK103 8K2408 8-WAY AMP CT CONN
SK300 8K2304 MOLEX MINI FIT HCS 4 WAY
SK301 8K6604 4-WAY FR LOCK CONN
Z100 5S408DY IC 8 TO 1 MUX DG408DY SO16
Z101 5S408DY IC 8 TO 1 MUX DG408DY SO16
Z102 5S408DY IC 8 TO 1 MUX DG408DY SO16
Z103 5S408DY IC 8 TO 1 MUX DG408DY SO16
Z104 5S408DY IC 8 TO 1 MUX DG408DY SO16
Z105 5S408DY IC 8 TO 1 MUX DG408DY SO16
Z106 5S413DY IC QUAD SPST CMOS SW SO16
Z107 5AVSDVC IC AUDIO DIGITAL VOL SM
Z108 5A1844 IC DS1844S-010
Z109 5B072D IC AUDIO SM DUAL TL072
Z110 5B072D IC AUDIO SM DUAL TL072
Z111 5B072D IC AUDIO SM DUAL TL072
Z112 5B072D IC AUDIO SM DUAL TL072
Z113 5B072D IC AUDIO SM DUAL TL072
Z114 5B072D IC AUDIO SM DUAL TL072
Z115 5B2134 IC OPAMP DUAL SM OPA2134PA
Z116 5B2134 IC OPAMP DUAL SM OPA2134PA
Z117 5B2134 IC OPAMP DUAL SM OPA2134PA
Z301 5D317T IC VREG POS LM317T
Page 41
4321
D
C
D
C
Main signal path
L937C2 1.1.SCH
B
Power supply
L937C3 1.1.SCH
B
USE EXCLUDE NF WHEN USING RUNOUT SHEET PROGRAM
DRAWING TITLE
Integrated amplifier preamp
PCB1
A
PCB
L937PB_1
23425
A & R Cambridge Ltd.
Pembroke Avenue
Notes:
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
1 2 3 4
Filename
J:\Change_Control\ECO_AGENDA\01_E014 Fuse changes on A32 preamp\L937_1.1.ddb - Documents\Schematic\L937C1_1.0.PRJ
Circuit Diagram
01_E014 JBR 28/11/01 Fuses uprated to 2A 1.1
01_1142 JBR 14/8/01 First production release 1.0
ECO No. DESCRIPTION OF CHANGE
Date Printed
INITIALS
28-Nov-2001
DATE
Drawn by:
JBR
1 3Sheet of
DRAWING NO.
L937C1
ISSUE
A
Page 42
87654321
D100
+15V -15V
BAV99W DUAL SM
SK2A
CDL1 CDL
0V_SIG
D101
BAV99W DUAL SM
D102
BAV99W DUAL SM
0V_SIG
TUNR1
D106
BAV99W DUAL SM
D107
BAV99W DUAL SM
0V_SIG
D108
BAV99W DUAL SM
D112
BAV99W DUAL SM
0V_SIG
D113
BAV99W DUAL SM
D114
BAV99W DUAL SM
0V_SIG
D115
BAV99W DUAL SM
D116
BAV99W DUAL SM
0V_SIG
D117
BAV99W DUAL SM
R100
1K0 SM
R101
1K0 SM
R102
1K0 SM
R125
1K0 SM
R126
1K0 SM
R127
1K0 SM
R156
1K0 SM
R157
1K0 SM
R158
1K0 SM
R189
1K0 SM
R190
1K0 SM
R191
1K0 SM
0V_SIG
0V_SIG
0V_SIG
0V_SIG
0V_SIG
0V_SIG
0V_SIG
0V_SIG
0V_SIG
0V_SIG
0V_SIG
0V_SIG
R103
100K SM
CDR
R104
100K SM
TUNL
R105
100K SM
TUNR
R128
100K SM
AVL
R129
100K SM
AVR
R130
100K SM
DVDL
R159
100K SM
DVDR
R160
100K SM
TAPEIL
R161
100K SM
TAPEIR
R192
100K SM
VCRIL
R193
100K SM
VCRIR
R194
100K SM
CD L
470P FKP2
CD R
0V_SIG
TUNER L
TUNER R
0V_SIG
AV L
AV R
0V_SIG
DVD L
DVD R
TAPE IN L
TAPE IN R
VCR IN L
VCR IN R
C101
C102
470P FKP2
C103
470P FKP2
C122
470P FKP2
C123
470P FKP2
C124
470P FKP2
C140
470P FKP2
C141
470P FKP2
C142
470P FKP2
C161
470P FKP2
C162
470P FKP2
C163
470P FKP2
CD INPUT
1
F
EMC
N
C100
1N0 SM
0V_SIG
D
TUNER INPUT
CDR1
PHONO4G
+15V -15V
+15V -15V
SK2B
TUNL1
F
N
PHONO4G
+15V -15V
+15V -15V
C
AV INPUT
SK3A
AVL1
1
F
EMC
N
C121
1N0 SM
0V_SIG
DVD INPUT
B
TAPE INPUT
AVR1
PHONO4G
+15V -15V
+15V -15V
SK3B
DVDL1
F
N
DVDR1
PHONO4G
+15V -15V
+15V -15V
SK4A
TAPEIL1
1
F
EMC
N
C139
1N0 SM
0V_SIG
VCR INPUT
A
C160
1N0 SM
0V_SIG
TAPEIR1
PHONO4G
+15V -15V
+15V -15V
SK5A
VCRIL1
1
F
EMC
N
VCRIR1
PHONO4G
+15V -15V
1 2 3 4 5 6 7 8
+15V
-15V
+15V
-15V
+15V
-15V
0V_SIG
C106
100N SM
C107
100N SM
C125
100N SM
C126
100N SM
C127
100N SM
C128
100N SM
0V_SIG
0V_SIG
+15V
C104
100N SM
C105
100N SM
-15V
0V_SIG
0V_SIG
0V_SIG
+15V
-15V
+15V
C145
100N SM
C146
100N SM
-15V
AUX INPUT
C164
1N0 SM
VCR2
C143
100N SM
C144
100N SM
PHONO2G
AUX L
CD L
TUNER L
AV L
DVD L
VCR IN L
MODULE L
0V_SIG
AUX R
CD R
TUNER R
AV R
DVD R
VCR IN R
MODULE R
TAPE 2
AUX L
CD L
TUNER L
AV L
DVD L
TAPE IN L
MODULE L
VCR01
AUX R
CD R
TUNER R
AV R
DVD R
TAPE IN R
MODULE R
AUX L
CD L
TUNER L
AV L
DVD L
TAPE IN L
VCR IN L
MODULE L
LIST2
AUX R
CD R
TUNER R
AV R
DVD R
TAPE IN R
VCR IN R
MODULE R
LISTEN0
LISTEN1
LISTEN2
D118
BAV99W DUAL SM
AUXIL1
1
TAPE 1
TAPE 2
TAPE 0
TAPE 1
LIST1
TAPE 0
0V_SIG
0V_SIG
VCR 2
0V_SIG
VCR 1
VCR 2
0V_SIG
LIST0
VCR 1
R162
22K SM
R163
22K SM
R164
22K SM
R165
22K SM
R166
22K SM
R167
22K SM
R168
22K SM
R169
22K SM
TAP0
TAP1
TAP2
TAPE0
TAPE1
TAPE2
VCR11
VCR21
VCR0
VCR1
+15V -15V
SK6
F
EMC
N
0V_SIG
AUXIR1
+15V -15V
D119
BAV99W DUAL SM
+5V
+5V
+5V
VCR 0
+5V
VCR 0
R195
1K0 SM
R196
1K0 SM
-15V
-15V
LISTEN 0
LISTEN 1
LISTEN 2
0V_SIG
LISTEN 0
LISTEN 1
LISTEN 2
0V_SIG
Z100
4
5
6
7
12
11
10
9
2
1
16
15
14
3
DG408DY
Z101
4
5
6
7
12
11
10
9
2
1
16
15
14
3
DG408DY
Z102
4
5
6
7
12
11
10
9
2
1
16
15
14
3
DG408DY
Z103
4
5
6
7
12
11
10
9
2
1
16
15
14
3
DG408DY
R170
22K SM
R171
22K SM
R172
22K SM
R173
22K SM
R174
22K SM
R175
22K SM
R176
22K SM
R177
22K SM
AUXL
0V_SIG
0V_SIG
X0
X1
X2
X3
X4
X5
X6
X7
EN
A0
A1
A2
GND
V-
X0
X1
X2
X3
X4
X5
X6
X7
EN
A0
A1
A2
GND
V-
X0
X1
X2
X3
X4
X5
X6
X7
EN
A0
A1
A2
GND
V-
X0
X1
X2
X3
X4
X5
X6
X7
EN
A0
A1
A2
GND
V-
+5V
+5V
R197
100K SM
AUXR
R198
100K SM
-15V
-15V
AUX L
AUX R
13
V+
8
D
13
V+
8
D
13
V+
8
D
13
V+
8
D
Z104
4
X0
5
X1
6
X2
7
X3
12
X4
11
X5
10
X6
9
X7
2
EN
1
A0
16
A1
15
A2
14
GND
3
V-
DG408DY
Z105
4
X0
5
X1
6
X2
7
X3
12
X4
11
X5
10
X6
9
X7
2
EN
1
A0
16
A1
15
A2
14
GND
3
V-
DG408DY
SK103
TO PHONO PCB
AMPCT8
C165
470P FKP2
C166
470P FKP2
+15V
0V_SIG
+15V-15V
0V_SIG
+15V
0V_SIG
+15V-15V
0V_SIG
1
2
3
4
5
6
7
8
R106
1M0 SM
R107
1M0 SM
R131
1M0 SM
R132
1M0 SM
V+
V+
0V_SIG
D
D
AUX R
AUX L
13
8
13
8
+15V
+15V
+15V1
0V_HF
0V_SIG
0V_SIG
-15V1
-15V
3
2
5
6
3
2
5
6
C147
100N PE
C167
100N PE
+15V
AUXR1
AUXL1
+15V -15V
D103
Z109A
TL072 SM
Z109B
TL072 SM
Z110A
TL072 SM
Z110B
TL072 SM
C148
22P SM
R178
22K SM
2
Z115A
3
OPA2134PA SM
C149
22P SM
R179
22K SM
2
Z116A
3
OPA2134PA SM
Z109C
TL072 SM
Z113C
TL072 SM
BAV99W DUAL SM
R108
1
47R SM
C108
100P SM
+15V -15V
D104
BAV99W DUAL SM
R109
7
47R SM
C109
100P SM
+15V -15V
D109
BAV99W DUAL SM
R133
1
47R SM
C129
100P SM
+15V -15V
D110
BAV99W DUAL SM
R134
7
47R SM
C130
100P SM
Z115_1A
1
R180
100K SM
R199
100K SM
84
-15V
84
-15V
7
OPA2134PA SM
+15V
1
7
OPA2134PA SM
C168
100N SM
0V_SIG 0V_SIG 0V_SIG 0V_SIG
C169
100N SM
-15V2
C170
100N SM
0V_SIG 0V_SIG 0V_SIG 0V_SIG 0V_SIG
C171
100N SM
470N PE
+
+
-15V
470N PE
C150
C151
Z115B
C188
10U EL
C189
10U EL
Z116B
TAPEO1
0V_SIG
TAPE02
VCRO1
0V_SIG
VCR02
Z116_1A
84
Z110C
TL072 SM
84
Z114C
TL072 SM
SK4B
PHONO4G
VCR OUTPUT
SK5B
PHONO4G
6
5
0V_SIG
0V_SIG
6
5
0V_SIG
TAPE OUTPUT
F
N
F
N
R183
1M0 SM
R184
1M0 SM
C172
100N SM
C173
100N SM
C174
100N SM
C175
100N SM
TONE*
C152
100N SM
0V_SIG
TONE*
84
Z111C
TL072 SM
84
Z115C
OPA2134PA SM
C176
100N SM
C177
100N SM
C178
100N SM
C179
100N SM
1
2
3
4
6
7
8
+
C110
100U EL
0V_SIG
+
C131
100U EL
0V_SIG
Z106
SEL1
D1
S1
VGND5VL
S4
D4
SEL4
DG413DY
+15V2
Z112C
TL072 SM
OPA2134PA SM
SEL2
SEL3
+15V
84
84
Z116C
+5V
R110
2K2 SM
R112
22K SM
R111
2K2 SM
Z115_1B
+5V
R135
2K2 SM
R137
22K SM
R136
2K2 SM
Z116_1B
TONE
+5V
C180
100N SM
C181
100N SM
C182
100N SM
C183
100N SM
/TONE
TONE*
OPA2134PA SM
16
15
D2
14
S2
13
V+
12
11
S3
10
D3
9
Z111_3
Z113_3
+15V-15V
0V_SIG
+15V
84
Z117C
R113
22K SM
+
R138
22K SM
+
Z111A
TL072 SM
3
2
C111
10U CERAFINE
Z113A
TL072 SM
3
2
C132
10U CERAFINE
+
C154
10U EL
Z107_4
C153
100N SM
Z107_13
0V_SIG
0V_SDATA
0V_SLOAD
0V_SCLK
C184
100N SM
C185
100N SM
Z111_7
Z113_7
1
1
0V_SIG
R182
100R SM
R200
2R2 SM
R201
2R2 SM
R202
2R2 SM
Z111_1
Z113_1
C155
100N SM
D105
BAV99W DUAL SM
0V_SIG
1618
Z108D
17
DS1844
5
6
D111
BAV99W DUAL SM
62
Z108B
7
DS1844
5
6
0V_SIG
C156
100N SM
1
0V_SIG
AVCC
SCLK
SDATA
SLOAD
+5V
C186
100N SM
0V_SIG
Z112_3
Z108_19
C113
470N PE
R115
2K7 SM
R116
2K7 SM
Z114_3
Z108_3
C134
470N PE
R140
2K7 SM
R141
2K7 SM
LFO
LMO
RFO
RMO
16
R181
10K SM
DS1844
0V_SIG
DS1844
0V_SIG
1519
53
+
C157
100U EL
3
2
14
15
Z107
VSDVC
Z108A
14
0V_SIG
Z108C
4
0V_SIG
0V_SIG
+
R117
5K6 SM
R142
5K6 SM
C187
10U EL
C114
CFKP2 63V 2N2
3
2
C135
CFKP2 63V 2N2
2
Z117A
3
OPA2134PA SM
6
Z117B
5
OPA2134PA SM
R114
22K SM
7
Z111B
TL072 SM
C112
470N PE
C192
470N PE
+5V
R139
22K SM
7
Z113B
TL072 SM
C133
470N PE
C193
470N PE
+5V
R185
22R SM
Z107_1
7
DVCC
4
LIN
5
LGND
13
RIN
12
RGND
DGND11XCS6DATA9CCLK10XMUTE8AGND
DRAWING TITLE
Integrated amplifier preamp - main signal path
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
Notes:
Filename
J:\Change Control\ECO AGENDA\01 E014 Fuse changes on A32 preamp\L937 1.1.ddb Documents\Schematic\L937C2 1.0 SCH
Circuit Diagram
Z112A
TL072 SM
3
2
Z114A
TL072 SM
C136
22P SM
+15V
+
+
-15V
D120
BAS16W SM
R118
22K SM
R143
22K SM
C190
10U EL
C191
10U EL
C158
22P SM
1
C159
22P SM
7
C115
22P SM
1
Z112B
TL072 SM
Z112_1
5
1
6
7
Z112_7
R119
22K SM
R120
22K SM
+
0V_SIG
Z114B
Z114_1
TL072 SM
5
7
6
+15V -15V
0V_SIG
SK102_1
R186
47R SM
SK102_3
R187
47R SM
0V_SIG
+5V
+-RLY100C
RLY DPDT 5V SM
Q100
BC849B
0V_D
10U CERAFINE
R144
22K SM
R145
22K SM
+
C137
10U CERAFINE
0V_SIG
D121
BAV99W DUAL SM
RLY100A
RLY DPDT 5V SM
R203
4K7 SM
01_E014 JBR 28/11/01 Fuses uprated to 2A 1.1
01_1142 JBR 14/8/01 First production release 1.0
ECO No. DESCRIPTION OF CHANGE
Date Printed
C117
+
10U CERAFINE
C116
10U CERAFINE
C138
Z106_11Z114_7
+
D122
BAV99W DUAL SM
RLY DPDT 5V SM
MUTE*
INITIALS
Z106_14
R121
22K SM
R146
22K SM
RLY100B
DATE
SCLK
SDATA
TONEID
0V_D
0V_TONEID
SK102
1
2
3
4
AMPCT4
TO POWER AMP I/P
Drawn by:
JBR28-Nov-2001
SCLK
SDATA
TONEID
IC DS1844
0V_TONEID
0V_SDATA
0V_SCLK
LISTEN 0
LISTEN 1
LISTEN 2
VCR 0
VCR 1
VCR 2
TAPE 0
TAPE 1
TAPE 2
TONE*
TONEID
0V_SDATA
13
12
R122
2R2 SM
R124
2R2 SM
R123
2R2 SM
SDATA
0V_SLOAD
0V_SIG
2 3Sheet of
9
MUTE*
+5V
CLK
DIN
RST
R147
22K SM
R148
22K SM
R149
22K SM
R150
22K SM
SLOAD
0V_SCLK
R188
10K SM
20
Z108E
VCC
1
PS
8
R/W
11
DOUT
GND
10
0V_SIG
SCLK
AUX L
AUX R
CD L
CD R
TUNER L
TUNER R
AV L
AV R
DVD L
DVD R
TAPE IN L
TAPE IN R
VCR IN L
VCR IN R
MODULE L
MODULE R
0V_MODULE
DRAWING NO.
C118
100N SM
R204
10K SM
C119
10N SM
R151
22K SM
R152
22K SM
R153
22K SM
R154
22K SM
R155
22K SM
FFC22V1MM
L937C2
+
C120
10U EL
SK100
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
TO MICRO / DISPLAY PCB
18
19
20
21
22
SK101
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
TO PLUG IN MODULE PCB
21
22
23
24
25
26
27
28
29
30
FFC30V SM
ISSUE
D
C
B
A
Page 43
4321
D302
BAS16W SM
Q305
2SA1964
D
C
SK300
MOLEXPWR4
3
4
1
2
F300
T2A SM
F301
T2A SM
AC1
C307
470N PE
AC2
D300
S1D
C308
100N SM
C309
100N SM
D301
S1D
UR+
+
C300
1000u 35V
Q300
J112
R300
330R SM
C314
1N0 PP
C315
1N0 PP
Q303
J112
Q306
BC846B
D310+
+
C302
220U EL
+
C312
220U EL
D311-
D310
15V 350MW SM
D311
15V 350MW SM
+15V
+
+
I
+15V3
C304
100N SM
C303
3300u 25V
C313
3300u 25V
Z301
LM317T
Vin
0V_PSU
D304
BAS16W SM
Vout
ADJ
A
+3.75V
R302
1K2 SM
R307
220R SM
O
+
C305
10U EL
-15V
D305
BAS16W SM
+15V
0V_PSU
0V_MODULE
R303
470R SM
SK301
1
2
3
4
IDC4S
+5V
+5V
+
C306
470U EL 25V
D
C
D306
S1D
B
D307
S1D
+
UR-
C310
1000u 35V
R304
330R SM
Q301
2SC5248
D308
BAS16W SM
Q307
BC856B
-15V
-15V3
SP300
STAR POINT 4
0V_HF 0V_MODULE
0V_PSU
0V SIG
0V_SIG
B
DRAWING TITLE
Integrated amplifier preamp - power supply
A
23425
Notes:
Circuit Diagram
01_E014 JBR 28/11/01 Fuses uprated to 2A 1.1
A
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
1 2 3 4
Filename
J:\Change_Control\ECO_AGENDA\01_E014 Fuse changes on A32 preamp\L937_1.1.ddb - Documents\Schematic\L937C3_1.0.SCH
01_1142 JBR 14/8/01 First production release 1.0
ECO No. DESCRIPTION OF CHANGE
Date Printed
INITIALS
28-Nov-2001
DATE
Drawn by:
JBR
3 3Sheet of
DRAWING NO.
L937C3
ISSUE
Page 44
3rd Channel
Board
L911
Contents
!
Component overlay
!
Parts list
!
Circuit diagrams
Page 45
Page 46
L911 3rd Channel Amplifier Board Parts List Issue 1.1
Designator Part Description
BR100 3BGBU8D BRIDGE RECTIFIER 8A 200V
C100 2C410 MLC 100N 50V X7R 10% SM
C101 2C410 MLC 100N 50V X7R 10% SM
C102 2N710 ELST 100U 25V
C103 2C310 MLC 10N 50V X7R 10% SM
C104 2C310 MLC 10N 50V X7R 10% SM
C105 2C210 MLC 1N0 50V X7R 10% SM
C106 2N910A ELST 10m 63V RA 35mm
C107 2N910A ELST 10m 63V RA 35mm
C108 2H410 PCRB 100N 100V 10% RA 5mm
C109 2H410 PCRB 100N 100V 10% RA 5mm
C300 2N710 ELST 100U 25V
C301 2N710 ELST 100U 25V
C302 2N710B ELST 100U 100V
C303 2N710 ELST 100U 25V
C304 2N710 ELST 100U 25V
C305 2N610 ELST 10U 50V
C306 2N710B ELST 100U 100V
C307 2C110 MLC 100P 50V NPO 5% SM
C308 2C110 MLC 100P 50V NPO 5% SM
C309 2C410 MLC 100N 50V X7R 10% SM
C310 2C410 MLC 100N 50V X7R 10% SM
C311 2H410 PCRB 100N 100V 10% RA 5mm
C312 2C310 MLC 10N 50V X7R 10% SM
C313 2C410 MLC 100N 50V X7R 10% SM
C314 2C410 MLC 100N 50V X7R 10% SM
C315 2C410 MLC 100N 50V X7R 10% SM
C316 2D147W PPRO W 470P 63V 5% RA
C317 2K447 PEST 470N 63V 10%
C318 2N610 ELST 10U 50V
C319 2K410 PEST 100N 63V 10%
C320 2V710 ELST NON POLAR 100UF 16V
D100 3B4003 RECTIFIER 1N4003F 1A 200V
D101 3B4003 RECTIFIER 1N4003F 1A 200V
D300 3AS16W DIODE SS SM BAS16W
D301 3AS16W DIODE SS SM BAS16W
D302 3AS16W DIODE SS SM BAS16W
D303 3B4003 RECTIFIER 1N4003F 1A 200V
D304 3B4003 RECTIFIER 1N4003F 1A 200V
DZ300 3CW315V ZENER 15V OW35 SM SOT23
DZ301 3CW315V ZENER 15V OW35 SM SOT23
DZ302 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ303 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ305 3CW34V7 ZENER 4V7 OW 35 SM SOT23
DZ306 3CW34V7 ZENER 4V7 OW 35 SM SOT23
IC100 5J7414D SURFACE MOUNT HEX SCHMITT TRIGGER
IC300 5B072D IC AUDIO SM DUAL TL072
L300 7D002C INDUCT 2U2 12x20mm
PB L911PB_1 PCB
PL300 8K6201 2WAY MOLEX VERT MALE CONNECTOR
R100 1A210 RES SM W4 1% 1K0 1206
R101 1A210 RES SM W4 1% 1K0 1206
R102 1A210 RES SM W4 1% 1K0 1206
R103 1A122 RES SM W4 1% 220R 1206
R104 1A122 RES SM W4 1% 220R 1206
R105 1A110 RES SM W4 1% 100R 1206
R106 1A110 RES SM W4 1% 100R 1206
R107 1A822 RES SM W4 1% 2R2 1206
R300 1A310 RES SM W4 1% 10K 1206
R301 1A310 RES SM W4 1% 10K 1206
R302 1A310 RES SM W4 1% 10K 1206
R303 1A310 RES SM W4 1% 10K 1206
Page 47
L911 3rd Channel Amplifier Board Parts List Issue 1.1
Designator Part Description
R304 1A310 RES SM W4 1% 10K 1206
R305 1A310 RES SM W4 1% 10K 1206
R306 1A310 RES SM W4 1% 10K 1206
R307 1A310 RES SM W4 1% 10K 1206
R308 1A322 RES SM W4 1% 22K 1206
R309 1A310 RES SM W4 1% 10K 1206
R310 1A247 RES SM W4 1% 4K7 1206
R311 1A310 RES SM W4 1% 10K 1206
R312 1A310 RES SM W4 1% 10K 1206
R313 1A310 RES SM W4 1% 10K 1206
R314 1A310 RES SM W4 1% 10K 1206
R315 1A110 RES SM W4 1% 100R 1206
R316 1A110 RES SM W4 1% 100R 1206
R317 1A110 RES SM W4 1% 100R 1206
R318 1A110 RES SM W4 1% 100R 1206
R319 1A110 RES SM W4 1% 100R 1206
R320 1A110 RES SM W4 1% 100R 1206
R321 1A022 RES SM W4 1% 22R 1206
R322 1A022 RES SM W4 1% 22R 1206
R323 1A022 RES SM W4 1% 22R 1206
R324 1A210 RES SM W4 1% 1K0 1206
R325 1A210 RES SM W4 1% 1K0 1206
R326 1A210 RES SM W4 1% 1K0 1206
R327 1A322 RES SM W4 1% 22K 1206
R328 1A247 RES SM W4 1% 4K7 1206
R329 1A247 RES SM W4 1% 4K7 1206
R330 1A510 RES SM W4 1% 1M0 1206
R331 1A215 RES SM W4 1% 1K5 1206
R332 1A218 RES SM W4 1% 1K8 1206
R333 1A233 RES SM W4 1% 3K3 1206
R334 1A322 RES SM W4 1% 22K 1206
R335 1A233 RES SM W4 1% 3K3 1206
R336 1A322 RES SM W4 1% 22K 1206
R337 1A022 RES SM W4 1% 22R 1206
R338 1A115 RES SM W4 1% 150R 1206
R339 1A115 RES SM W4 1% 150R 1206
R340 1A410 RES SM W4 1% 100K 1206
R341 1A133 RES SM W4 1% 330R 1206
R342 1A133 RES SM W4 1% 330R 1206
R343 1A110 RES SM W4 1% 100R 1206
R344 1A110 RES SM W4 1% 100R 1206
R345 1A000 RES SM W4 1% 0R0 1206
R346 1A000 RES SM W4 1% 0R0 1206
R347 1A110 RES SM W4 1% 100R 1206
R348 1A110 RES SM W4 1% 100R 1206
R349 1A110 RES SM W4 1% 100R 1206
R350 1C856 RES CF 2W 5R6 5%
R351 1C856 RES CF 2W 5R6 5%
R352 1J147 RES 2W MF 5% 470R
R353 1J147 RES 2W MF 5% 470R
R354 1A210 RES SM W4 1% 1K0 1206
R355 1A268 RES SM W4 1% 6K8 1206
RLY100 A213 RLY SPST 24V SPKR
RLY101 A213 RLY SPST 24V SPKR
RV300 6F110 PRES 100R LIN HORIZ
SK100 8K7014 FFC 14W 2.54MM VER PTH
SK101 8D226 PHONO SKT 2-WAY EMC GOLD
SK102 8D418G CAMCON BINDING POST 4WAY GOLD
SK103 8K2304 MOLEX MINI FIT 4 WAY
TH100 1T002 THERMISTOR SIEMENS B59008
TR100 4B179 NPN TRANS MP BD179
TR101 4B179 NPN TRANS MP BD179
Page 48
L911 3rd Channel Amplifier Board Parts List Issue 1.1
Designator Part Description
TR300 4AFMMT597 TRANS LF SS P SM FMMT597
TR301 4AFMMT597 TRANS LF SS P SM FMMT597
TR302 4AFMMT597 TRANS LF SS P SM FMMT597
TR303 4AFMMT597 TRANS LF SS P SM FMMT597
TR304 4AFMMT597 TRANS LF SS P SM FMMT597
TR305 4AFMMT597 TRANS LF SS P SM FMMT597
TR306 4AFMMT597 TRANS LF SS P SM FMMT597
TR307 4AFMMT597 TRANS LF SS P SM FMMT597
TR308 4AFMMT597 TRANS LF SS P SM FMMT597
TR309 4AFMMT497 TRANS LF SS N SM FMMT497
TR310 4AFMMT497 TRANS LF SS N SM FMMT497
TR311 4AFMMT497 TRANS LF SS N SM FMMT497
TR312 4AFMMT497 TRANS LF SS N SM FMMT497
TR313 4AFMMT497 TRANS LF SS N SM FMMT497
TR314 4AFMMT497 TRANS LF SS N SM FMMT497
TR315 4AFMMT497 TRANS LF SS N SM FMMT497
TR316 4AFMMT497 TRANS LF SS N SM FMMT497
TR317 4AFMMT497 TRANS LF SS N SM FMMT497
TR318 4CSAP15N TRANS POWER NPN SAP15N
TR319 4CSAP15P TRANS POWER PNP SAP15P
TR320 4AFMMT497 TRANS LF SS N SM FMMT497
TR321 4AFMMT597 TRANS LF SS P SM FMMT597
TR322 4AFMMT497 TRANS LF SS N SM FMMT497
Page 49
87654321
+5V_D
SK100
D
+5V_D
14
IC100G
74HC14D
7
C100
100N SM
+
C102
100U EL
C101
100N SM
R100
1K0 SM
TH100
PTH90DEG
IC100E
74HC14D
IC100F
1011
1213
FFC 14W 2.54MM VER
PIN 1 TO THE LEFT AS YOU LOOK FROM THE FRONT
THERMPROT
TP102
1
2
3
4
5
SPKR1 ON
6
SPKR2 ON
7
THERMPROT
8
VIPROT1
9
DCPROT1
10
11
12
13
14
TP103
+5V_D
TP104
TP105
TP106
TP107
TP108
0V_D
0V_D
0V_SIG
TP116
0V_LS 0V_HF
SP100
STAR POINT 8
0V_PSU
R107
2R2 SM
D
0V_D
0V_D
C
+49V
D100
1N4003F
TR100
BD179
B
RLY101B
RLY SPST SPKR
R103
220R SM
0V_D
TR101
BD179
RLY100B
RLY SPST SPKR
R105
100R SM
R106
100R SM
R104
220R SM
74HC14D
D101
1N4003F
SPKR1 ON
SPKR2 ON
0V_SIG
EMC
C105
1N0 SM
TP110
SK101
F
N
PHONO2G
1
TP109
+49V
-49V
0V_HF
0V_LS
L911C2_1
L911C2_1.1.SCH
INPUT
0V_SIG
0V_HF
VPOS
VNEG
VIPROT
DCPROT
OUTPUT0V_LS
R101
1K0 SM
R102
1K0 SM
TP111
1 2
C103
10N SM
5 6
C104
10N SM
0V_D
RLY101A
RLY SPST SPKR
TP112 TP113
IC100A
74HC14D
IC100C
74HC14D
3 4
SK102A
Top+
Top-
0V_LS
IC100B
74HC14D
IC100D
74HC14D
RLY100A
RLY SPST SPKR
C
VIPROT1
89
DCPROT1
SK102B
Bot+
Bot-
B
+49V
TP100
1
BR100
TP114
1
2
SK103
3
A
MOLEXPWR4
4
TP115
1 2 3 4 5 6 7 8
3
BRGBU8D
+
2
~
~
-
4
-49V
+
C106
10,000u 63V
+
C107
10,000u 63V
C108
100N PC
0V_PSU
C109
100N PC
POWER AMP SUPPLY
TP101
PB
PCB
L911PB_1
DRAWING TITLE
AP85 third channel - top level
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
Notes:
Filename
J:\ECO wip\01 1101 A85 RANGE PCB FUSES AND DC OFFSET\L911 1.1.DDB - Documents\ 911C1 1.1.PRJ
Circuit Diagram
01_1101 JR 4/6/01 DC OFFSET CHANGES 1.1
01_1018
ECO No. DESCRIPTION OF CHANGE
Date Printed
JR 30/1/01 PRODUCTION ISSUE 1.0
INITIALS
4-Jun-2001
DATE
Drawn by:
J Reckless
1 2Sheet of
DRAWING NO.
L911C1
A
ISSUE
Page 50
87654321
D
R315
TR300
FMMT597
C310
100N SM
3
2
C314
100N SM
TR314
FMMT497
100R SM
PNP CURRENT MIRROR
TR311
FMMT497
R328
4K7 SM
TP302
84
0V_SIG
IC300A
TL072CD
TP303
TR303
FMMT597
NPN CURRENT MIRROR
R317
100R SM
R300
10K SM
+
C300
DZ300
100U EL
15V 350MW SM
0V_HF
0V_SIG
C
INPUT
0V SIG
0V_HF
B
NPUT FILTER V TO I AMP
R324
1K0 SM
DZ302
4V7 350MW SM
DZ303
4V7 350MW SM
0V_SIG
+
C301
100U EL
0V_HF
C309
100N SM
DZ301
15V 350MW SM
R309
10K SM
R327
22K SM
C316
470P PPW
0V_SIG
7
1
C317
470N PE
IC300B
TL072CD
R322
22R SM
R337
22R SM
0V_SIG
R319
100R SM
R333
3K3 SM
DC SERVO
0V_SIG
TP304
R335
3K3 SM
R320
100R SM
R330
6
1M0 SM
5
R331
1K5 SM
R332
1K8 SM
C307
100P SM
TR322
FMMT497
C311
100N PC
C308
100P SM
R316
100R SM
TR301
FMMT597
TR321
FMMT597
R355
6K8 SM
R354
1K0 SM
TR320
FMMT497
TR315
FMMT497
R318
100R SM
TR309
FMMT497
R338
150R SM
BOOTSTRAP
+
C302
100U EL 100V
R352
470R 2W
470R 2W
R353
+
C318
10U EL
+
C306
100U EL 100V
BOOTSTRAP
R339
150R SM
TR306
FMMT597
PRE DRIVER
TR310
FMMT497
R321
22R SM
C312
10N SM
R323
22R SM
TR307
FMMT597
PRE DRIVER
ADJ BIAS
RV300
100R PSET
D300
BAS16W SM
OUTPUT STAGE
TR318
SAP15N
TP305
R325
1K0 SM
R340
100K SM
R326
1K0 SM
TP306
TR319
SAP15P
OUTPUT STAGE
PL300
1
2
MEASURE
BIAS
R341
330R SM
R342
330R SM
R343
100R SM
R344
100R SM
V-I PROTECTION
R334
22K SM
R347
100R SM
R345
0R0 SM
+
C303
100U EL
+
C304
100U EL
R346
0R0 SM
R348
100R SM
R336
22K SM
V-I PROTECTION
D301
BAS16W SM
TR312
FMMT497
TR304
FMMT597
D302
BAS16W SM
D303
1N4003F
DC OFFSET SIGNAL
TO MICRO
D304
1N4003F
0V_HF
R349
100R SM
DCPROT
TR305
FMMT597
TP308
DZ306
4V7 350MW SM
R302
10K SM
R310
4K7 SM
C315
100N SM
R301
10K SM
R329
4K7 SM
TR313
FMMT497
R303
10K SM
R304
10K SM
R311
10K SM
R312
10K SM
0V_HF
TR316
FMMT497
TR308
FMMT597
TR302
FMMT597
R305
10K SM
+
R306
10K SM
DC OFFSET
DETECTION
R307
10K SM
R313
10K SM
TR317
FMMT497
VI PROTECT
SIGNAL TO MICRO
TP307
C305
10U EL
VIPROT
DZ305
4V7 350MW SM
R308
22K SM
0V_HF 0V_LS
C320
100U NP
R350
5R6 2W CF
C319
100N PE
R314
10K SM
R351
5R6 2W CF
L300
2U2H LAC SMALL
ZOBEL NETWORK
C313
100N SM
VPOS
OUTPUT
0V LS
0V HF
VNEG
D
C
B
A
A
DRAWING TITLE
AP85 third channel - output stage
23425
A & R Cambridge Ltd.
Pembroke Avenue
Denny Industrial Centre
Waterbeach
Cambridge CB5 9PB
1 2 3 4 5 6 7 8
Notes:
Filename
L911C2 1.1.SCH
Circuit Diagram
01_1101 JR 4/6/01 DC OFFSET CHANGES 1.1
JR 30/1/01 PRODUCTION ISSUE 1.001_1018
INITIALS
DATE
Drawn by:
J Reckless4-Jun-2001
2 2Sheet of
DRAWING NO.
L911C2
ECO No. DESCRIPTION OF CHANGE
Date Printed
ISSUE
Page 51
Transformer
Specifications
Contents
!
L914TX
!
L915TX
Page 52
Page 53
Page 54
Mechanical
Assembly
Contents
!
General assembly
parts list A32
!
General assembly
parts list P35
!
General assembly
parts list P35/3
Page 55
A32 General Assembly Parts List E047rs_2
ITEM 230V 115V 100V SILVER BLACK DESCRIPTION WHERE USED QTY
A L813RC HANDY REMOTE 3 DIVA/DIVA SERIES CR389 1
B L907TX TRANSF A85 100V 1
1 E045AY E045AYB FRONT PANEL ASSEMBLY 1
7 E838CP E838CPB COVER 1
39 E839AY E839AYB LARGE VOLUME KNOB 1
35 HA4V06S HA4V06B M4 x 6mm Screw COVER TO CHASSIS 4
54 N/A N/A
2 E046AY REAR PANEL ASSEMBLY 1
3 E804HK HEAT SINK 1
4 E804MI MAINS INSULATOR ON CHASSIS FLOOR UNDER POWER
SUPPLY PCB
5 E820CH CHASSIS 1
6 E822PM1 FOOT 6
8 E850MC HEAT SHUNT ON CHASSIS FLOOR 1
9 E853MC PRE AMP REG CLAMP E850MC 1
10 E860MC DIVA A85 MODULE SLOT BLANKING PANEL 1
51 E878MC PHONO BOARD BRACKET FIXES PHONO BOARD 1
38 E879SL CONFIGURATION LABEL CHASSIS 1
40 E907MC KOOL PAD HEATSINK 1
12 E912MC TRANSISTOR CLAMP ON E804HK 4
13 E920MC HEATSINK CLAMP ON E804HK 1
14 E938MC DAMPING PLATE ON CHASSIS FLOOR 1
16 F022 FUSE HOLDER COVER 2
17 F037 TOROID CLAMP ø90 TOP OF TRANSFORMER 1
18 F038 RUBBER WASHER ø90 ON TOP OF TRANSFORMER 1
19 F062 FUSE CLIP SPARE FUSE 1
20 F065 ADHESIVE CABLE CLIP TRANSFORMER 1
21 F082 TO220 SIL PAD UNDER VOLTAGE REG 3
41 F164 FOAM TAPE FRONT PANEL TO COVER 400mm
49 E83001 TRANSFORMER GASKET UNDER TRANSFORMER 1
22 HA3V10A M3 x 10mm SCREW HEATSHUNT 2
48 HA3V06A M3 x 6mm SCREW POWER, PREAMP & DISPLAY PCB’S 31
37 HA4A12B M4 x 12mm SCREW EARTHING SCREWS 2
24 HA5K70A M5 x 70mm BOLT HEATSINK SCREWS 3
23 HA5L20B M5 x 20mm HEX HEAD BOLT BLACK TRANSISTORS TO HEATSINK 4
25 HA6K60A M6 x 60mm BOLT TRANSFORMER 1
47 HE6V06B SFTP TORX SCREW NO.6x6mm BK 4
46 HF4V09B TORX SCREW NO.4x9mm + WASHER 20
36 HJ4A00A M4 NUT EARTHING NUT 1
42 HJ4C00D M4 WAISTED NUT EARTH 1
43 HL4SB M4 SHAKE PROOF WASHER EARTH 1
44 HL5EB M5 WASHER BLACK HEATSINK SCREWS 3
52 HP008 PLASTIC SNAP RIVET E878MC TO L870AY 1
45 HP008 SNAP RIVET BLACK PLASTIC BLANKING PLATES 4
1
Page 56
A32 General Assembly Parts List E047rs_2
ITEM 230V 115V 100V SILVER BLACK DESCRIPTION WHERE USED QTY
A L813RC HANDY REMOTE 3 DIVA/DIVA SERIES CR389 1
B L907TX TRANSF A85 100V 1
50 L870AY PHONO PCB THROUGH REAR PANEL 1
28 L882AY WA8511A L894AY A85 POWERAMP PCB 1
31 L914CA DISPLAY TO PRE AMP CABLE ASSY 1
30 L914TX L915TX A32 TRANSFORMER 1
32 L915CA DISPLAY TO POWERAMP CABLE ASSY 1
33 L916CA POWERAMP TO HEADPHONE CABLE ASSY 1
34 L917CA PREAMP TO POWERAMP CABLE ASSY 1
53 L918CA PHONO TO PREAMP CABLE ASSY 1
29 L928AY A32 DISPLAY PCB 1
27 L937AY A32 PREAMP PCB 1
Page 57
P35 General Assembly Parts List E078rs_2
ITEM 230V 115V 100V SILVER BLACK DESCRIPTION WHERE USED QTY
1 E058AY E058AYB FASCIA ASSEMBLY FRONT OF CHASSIS 1
2 E838CP E838CPB COVER 1
3 HA4V06S HA4V06B M4 x 6mm Screw COVER (SIDE) TO CHASSIS 4
4 8K004 2-WAY JUMPER SOCKET 0.1” M7571-05 ON L882AY (NEAR SWITCH) 2
5 8K006 CONNECTOR 14MM LINK BA R P2148 FITTED TO REAR PANEL 1
7 E060AY REAR PANEL ASSEMBLY CHASSIS REAR 1
8 E804HK HEAT SINK CHASSIS FLOOR 1
9 E804MI MAINS INSULATOR ON CHASSIS FLOOR UNDER POWER
SUPPLY PCB
10 E820CH CHASSIS 1
11 E822PM1 FOOT BASE OF CHASSIS 6
12 E861MC 3RD CHANNEL BLANKING PLATE REAR PANEL 1
13 E879SL CONFIGURATION LABEL CHASSIS 1
14 E907MC KOOL PAD HEATSINK 1
15 E912MC TRANSISTOR CLAMP HEATSINK 4
16 E920MC HEATSINK CLAMP HEATSINK 1
17 E938MC DAMPING PLATE ON CHASSIS FLOOR 1
18 F022 FUSE HOLDER COVER 2
19 F037 TOROID CLAMP ø90 (METAL) TOP OF TRANSFORMER 1
20 F038 RUBBER WASHER ø90 ON TOP OF TRANSFORMER 1
21 F164 FOAM TAPE FRONT PANEL TO COVER 400m
22 F200 9,5 I.D. HOLE BLANKING GROMMET REAR PANEL (FOR LINK BAR) 2
23 E83001 TRANSFORMER GASKET UNDER TRANSFORMER 1
24 HA3V06A M3 x 6mm SCREW POWER & DISPLAY PCB’S 17
25 HA4A12B M4 x 12mm SCREW EARTHING SCREW 1
26 HA5K70A M5 x 70mm BOLT HEATSINK BOLTS 3
27 HA5L20B M5 x 20mm HEX HEAD BOLT BLACK TRANSISTORS TO HEATSINK 4
28 HA6K60A M6 x 60mm BOLT TRANSFORMER 1
29 HE6V06B SFTP TORX SCREW NO.6x6mm BK CHASSIS TO SUB PANEL 4
30 HF4V09B TORX SCREW NO.4x9mm + WASHER COMPONENTS TO REAR PANEL +
COVER TO REAR PANEL + REAR
PANEL TO CHASSIS
31 HJ4A00A M4 NUT EARTHING NUT 1
32 HJ4C00D M4 WAISTED NUT EARTH 1
33 HL4SB M4 SHAKE PROOF WASHER EARTH 1
34 HL5EB M5 WASHER BLACK HEATSINK BOLT (AT THE FRONT) 1
35 L882AY WA8511A L894AY A85 POWERAMP PCB CHASSIS FLOOR 1
36 L884TX L884TX L880TX TRANSFORMER CHASSIS FLOOR 1
37 L915CA DISPLAY TO POWERAMP CABLE ASSY L882AY TO L929AY 1
38 L929AY P35 SWITCH PCB SUB PANEL 1
1
m
16
Page 58
P35/3 Channel General Assembly Parts List E079rs_2
ITEM 230V 115V 100V SILVER BLACK DESCRIPTION WHERE USED QTY
1 E058AY E058AYB FASCIA ASSEMBLY FRONT OF CHASSIS 1
2 E839CP E839CPB COVER 1
3 HA4V06S HA4V06B M4 x 6mm Screw COVER (SIDE) TO CHASSIS 4
4 8K004 2-WAY JUMPER SOCKET 0.1” M7571-05 ON L882AY (NEAR SWITCH) 2
5 8K006 CONNECTOR 14MM LINK BAR P2148 FITTED TO REAR PANEL 1
7 E060AY REAR PANEL ASSEMBLY CHASSIS REAR 1
8 E804HK HEAT SINK CHASSIS FLOOR 1
9 E804MI MAINS INSULATOR ON CHASSIS FLOOR UNDER POWER
SUPPLY PCB
10 E806HK HEAT SINK CHASSIS FLOOR 1
11 E820CH CHASSIS 1
12 E822PM1 FOOT BASE OF CHASSIS 6
13 E879SL CONFIGURATION LABEL CHASSIS 1
14 E907MC KOOL PAD HEATSINK 1
15 E909MC 3RD CHANNEL SIL PAD HEATSINK 1
16 E912MC TRANSISTOR CLAMP HEATSINKS 6
17 E921MC HEATSINK CLAMP HEATSINK 1
18 2
19 E938MC DAMPING PLATE ON CHASSIS FLOOR 1
20
21 F037 TOROID CLAMP ø90 (METAL) TOP OF TRANSFORMER 1
22 F038 RUBBER WASHER ø90 ON TOP OF TRANSFORMER 1
23 F164 FOAM TAPE FRONT PANEL TO COVER 400m
24 F200 9,5 I.D. HOLE BLANKING GROMMET REAR PANEL (FOR LINK BAR) 2
25 E83001 TRANSFORMER GASKET UNDER TRANSFORMER 1
26 HA3V06A M3 x 6mm SCREW PCB’S 22
27 HA4A12B M4 x 12mm SCREW EARTHING SCREW 1
28 HA5K70A M5 x 70mm BOLT HEATSINK BOLTS 5
29 HA5L20B M5 x 20mm HEX HEAD BOLT BLACK TRANSISTORS TO HEATSINK 6
30 HA6K60A M6 x 60mm BOLT TRANSFORMER 1
31 HE6V06B SFTP TORX SCREW NO.6x6mm BK CHASSIS TO SUB PANEL 4
32 HF4V09B TORX SCREW NO.4x9mm + WASHER COMPONENTS TO REAR PANEL +
COVER TO REAR PANEL + REAR
PANEL TO CHASSIS
33 HJ4A00A M4 NUT EARTHING NUT 1
34 HJ4C00D M4 WAISTED NUT EARTH 1
35 HL4SB M4 SHAKE PROOF WASHER EARTH 1
36 HL5EB M5 WASHER BLACK HEATSINK BOLT (AT THE FRONT) 1
37 L882AY WA8511A A85 POWERAMP PCB CHASSIS FLOOR 1
38 L884TX L884TX L880TX TRANSFORMER CHASSIS FLOOR 1
39 L911AY WA85Q1A 3RD CHANNEL PCB CHASSIS FLOOR 1
40 L915CA SWITCH TO POWERAMP CABLE ASSY L882AY TO L929AY 2
41 L919CA SWITCH TO 3RD CHANNEL CABLE ASSY 1
42 L929AY WFA35P 1A P35 SWITCH PCB SUB PANEL 1
1
m
16
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ARCAM
All parts can be ordered via spares@arcam.co.uk
Pembroke Ave, Waterbeach, Cambridge, CB5 9PB, ENGLAND
TEL: +44(0) 1223 203 203 FAX: +44(0) 1223 863 384
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