McIntosh C2500 Service Manual page 15

3 CONTROL
751457 SCH 4 of 5
8 18V
J7:7
8
18V
J7:6
8
J7:5
8
J7:4
8
J7:3
8 -18V
J7:2
8
-18V
J7:1
J6:7
8
8V_UNREG
J6:6
8
8V_UNREG
J6:5
8
J6:4
8
J6:3
8
J6:2
8
AC W INDING
R275
OPEN
J6:1
8
15V
POWER TEST LEDs
DS2
R220 22.1K
VFD 5V
DS3
R218 47.5K
12V_PC
DS4
R236 10K
3.3V BU
DS5
R237 22.1K
5V
DS6
R238 10K
3.3V
DS7
R239 47.5K
15V
LED Ho ld-off B ias
R274 1K
15V
ON OFF
DGND
GND
7
J24:1
DGND
+VBU
7
+VBU
J24:2
POWER
7
RLY
J24:3
1
Q26
DGND
TUBE PREAMPLIFIER
AC W INDING
AC DETECTOR
1
NP1
No Pop
DGND
1
Q25
DGND
S1
Pwr_Supply
C37
10uF
.1UF C38
3.3V BU
3.3V BU
DGND
R47 10K
1
R48
VCC Power_Relay
4
High=Off, L ow=On
2
2.21K
GND
AC P wrUp n oise filte r
U15
0.1 se c d elay
133724
LVC NAND
DGND
25
C2500
18V
R36
Power_On
50k internal pulldown
Low = Enable
High = Disable
-18V
R20
Power_On
50k internal pulldown
Low = Enable
High = Disable
8V_UNREG
R22
Power_On
50k internal pulldown
Low = Enable
High = Disable
8V_UNREG
R41
Power_On
50k internal pulldown
Low = Enable
High = Disable
DGND
U12
1 B+
4
AC DET 8V_UNREG
2
GND
VFD PS ON
50k internal pulldown
Low = Enable
High = Disable
DGND
DGND
+VBU
50k internal pulldown
Low = Enable
High = Disable
18V
Power_On
U16
50k internal pulldown
133502
Low = Enable
1 B+
High = Disable
4
LVC AND
Power_On
2
GND
C43 .1UF
DGND 3.3V BU
DGND
R34
OPEN
U6
133717, 1.25A
L5
4 5 2 1
IN TAB OUT
15V
___
22.1 2
ON/OFF
? mA Max
3
GND ADJ
R13
R23
18.2K 1K
HS4
U9
L6
3 5 2 1
IN TAB OUT -15V
___
22.1 2
ON/OFF
? mA Max
4
GND ADJ
R32
1K
5V MISC
U10
133717, 1.25A
L7
4 5 2 1
5V
IN TAB OUT
Mute Relay s
___
22.1 2
ON/OFF Fiber optic LEDs
100mA Max ?
3
USB PCB
GND ADJ
R39 47.5K
U11 3.3V MISC
133717, 1.25A
L8
4 5 2 1
IN TAB OUT 3.3V
22.1 2 ___
ON/OFF
60mA Max?
3
GND ADJ
R44 100K
INFO VFD PS
U13
133717, 1.25A
L9
4 5 2 1
IN TAB OUT VFD 5V
___
2
ON/OFF
440mA Max
OPEN
C35
3
GND ADJ
47.5K
R46
3.3V BACKUP PS
U14
133717, 1.25A
L10
4 5 2 1
IN TAB OUT 3.3V BU
___
2
40mA Max
ON/OFF
3 (During Standby)
GND ADJ
R51
100K
12V P.C.
U29
133717, 1.25A
L29
4 5 2 1
IN TAB OUT 12V_PC
___
2
ON/OFF
125mA Max
3
GND ADJ
R176 56.2K
Vout = 1.24x(1+R1/R2)
GP3:1
GP3:2
GP3:3
GP3:4
26
15V
Audio Sw itching
Audio Outputs
USB Audio
-15V
Audio Sw itching
Audio Outputs
USB Audio
Logic Gates- ON Mode
USB PCB
Atmel micro
Standby LED
Front/Rear IR Sensors
Data In
Power Control In
Power Control