McIntosh C2500 Service Manual page 28

6 DIGITAL AUDIO
751120 SCH 3 of 3
3.24V
1 2 3.24V
3.24V
Y5
R173
L14
1 4
E/D VDD
OPEN
2 3
GND OUT
0V
R16 22.1
PLRCK
R79 22.1
PDATA
R18 22.1
PBCK
R7 22.1
SYS-CLK
R19 22.1
ADDR-0
R22 22.1 ADDR-1
R25 22.1 SCL
SCL
R26 22.1
SDA
SDA
RST
DA Run
DA Reset DA RESET/
R186 OPEN
C26
SP3
.1uF
C27
SP2
.1uF
R187 OPEN
51
R174
100K
1.65V
L6
U6
133757 TI PCM1795DB
1 28
ZEROL VCC2L
2 27
ZEROR AGND3L
3 26
MSEL IOUTL-
4 25
LRCK IOUTL+
5 24
PDATA AGND2
6 23
BCK VCC1
7 22
SCL VCOML
C11 47uF
8 21
DGND VCOMR
C14 47uF
9 20
VDD IREF
10K
R23
10 19
M\S\ AGND1
11 18
MDI IOUTR-
12 17
MC IOUTR+
13 16
MDO AGND3R
14 15
R\S\T\ VCC2R
R4 R5
475 332
C3
1000pF
15V-OP
2
-
0V
R8 R9 R10
1.5K 1.82K 1.82K
B+
1
U4:1
B-
-2.75V
3
+
0V
6
-
-1.38V
-14.5V-OP
U8:2
5
+
-1.38V
5
+
0V
R13 R14 R15
1.5K 1.82K 1.82K
-2.75V
7
U4:2
6
-
0V
C13 1000pF
15V
R20 R21
475 332
R182
47.5K
Unlocked
Good Signal CONV UNLOCKED
Muted
Unmuted DA AUDIO MUTE
R57 R58
475 332
C33 1000pF
15V-OP
2
-
0V R61 R62
R60
1.82K 1.82K
1.5K
B+
1
U9:1
B- -2.75V
3
+
0V
6
-
-1.38V
-14.5V-OP
U10:2
5
+
-1.38V
5
+
0V
R64 R65 R66
1.5K 1.82K 1.82K
-2.75V
7
U9:2
-15V
6
-
0V
1000pF
C41
R69 R70
475 332
J10:1
DA-L
R176
0
R6 J10:5
1.5K
J10:7
J10:3
DA-R
C4
330pF
R24
1K
7
0V
-15V-OP
3
+
0V
B-
1
U8:1
B+ 0V
2
-
0V
R63
-14.5V-OP
15V-OP
C23 1000pF
22.1
R32
2.21K
Unmuted 5.1V
U2
Muted
1
R38
Vcc
4 1
Q4
2 0V
GND
10K
4.5V
L L = H
L H = L
5V
H L = L
Muted
Unmuted
H H = L
-15.4V
R59
2.21K
1.5K
R51
C29 1000pF
C34
330pF
15V-OP
2
-
0V
B+
1
U10:1
B- 0V
R55
7 3
+
0V 0V
1K
-14.5V-OP
R67
-15V-OP
22.1
52
4 J3:12
4 J3:8
TO
AUDIO
4 PCB
J3:6
4 J3:10
R27
C22
475
DA-L
10uF
0V
R37 .77V
1K
1
Q3
0V
0V
.77V
1
Q6
1K
R40
0V
C28
DA-R
475
10uF
R53