Yamaha Mx12.6 Service Manual

							MX12/6
MX20/6
11
+30dB
+20dB
+10dB
0dB
–10dB
–20dB
–30dB
–40dB
–50dB
–60dB
STEREO [0dB]2dB]FECT [-6dB]EREO [-6dB]Max. Before Clip
AUX SEND [+4dB]
EFFECT SEND [+4dB]
AUX
EFFECT
Control MasterGROUP
Fader MasterMax. Before Clip
GROUP OUT [+4dB]
REC OUT [-10dBV]
ST
FaderMasterMONO Master 
ControlMax. Before Clip
ST OUT, MONO OUT [+4dB]
C-R/PHONESC-R/PHONES [+4dB@10kohms]
C-R/PHONES
[3mW@40ohms]
STEREO R
EFFECTSTEREO LGROUP4AUX1
AUX2 STEREO R
EFFECT STEREO L
GROUP4AUX1
AUX2
GROUP1 Fader
[0dB]
INV
INV
INV
INV SUM
SUM SUMSUM[0dB]
[0dB]
[0dB]
[0dB]
[0dB][-10dB]
GROUP2 Fader[-10dB]
GROUP3 Fader[-10dB]
GROUP4 Fader[-10dB]
GROUP OUT 1[+4dB]
GROUP OUT 2[+4dB]
GROUP OUT 3[+4dB]
GROUP OUT 4[+4dB]
SUM SUM
INVINV
[0dB][0dB]BA
BA ST Fader
[-10dB]
BA
SUM
REC OUT
[-10dBV][-6dB]R LGEQ GEQST OUT L
[+4dB]
ST OUT R[+4dB]
MONO OUT[+4dB]
SUM
SUM[0dB]
[0dB]AUX1 SEND[+4dB]
AUX2 SEND[+4dB]
AUX1[-6dB]
AUX2[-6dB]
INV
INV
SUMINV
EFFECT SEND
[+4dB]EFFECT[-6dB]
PROGRAM
PARAMETERDIGITAL
EFFECT(INV)LO
RO
[0dB]
IN
G1-2/G3-4
ST/GROUP
TAPE IN
C-R/PHONES
[-16dB]
BA BA DR DR
C-R/PHONES[3mW@40ohms]
[+4dB@10kohms]
LEVEL(LED)METERPEAKPEAK
TO ST
TO ST
MONO
A A
1/4
ICJ01
ICJ51
IC102
21 ICF01
21ICD01
21ICD02
JK301
JK302
JK303
JK304 21
ICD01
67ICD02
67
ICE01
21ICE02
21
ICE01
67ICE02
67
ICG01
21ICG01
67ICF01
67ICF02
ICF03
ICG03 21
ICF02
ICH01 67
21
ICI01
21
ICI61
67ICI61
21 ICI01
67ICI31
JK306
JK307
JK308 21
ICI51
67ICH01
67ICF04 JKF51
21
57
ICG04 JKG51
21
57
ICH04 JKH51
67
31
67
IC102JKJ01
MAIN
1/4 MAIN2/2 DCJK
2/2 DCJK
2/2 DCJK
1/4 MAIN
1/4 MAIN
CN201-10CN301-1 CN202-14
CN302-1
CN202-12
CN302-3
CN202-10
CN302-5
CN202-8
CN302-7
CN201-8CN301-3
CN201-6
CN204-11
CN204-10 CN304-3 CN204-4~8
CN304-5~9
CN304-10~12CN204-1~3
CN304-4
CN204-9 CN304-2CN301-5 
						

							MX12/6
MX20/6
12
WIRING
CN208
A ACN404
CN401 CN501
CN502
CN402CN403CN203
CN303
(
MX20/6 only)(
MX12/6 only)
CN
2/22/4
1/2
(
MX12/6)
to MAIN1/4 CN207
IN8-CN403
(
MX20/6)toMto IN
IN8MAIN
IN8
M DCJ
K 
						

							MX12/6
MX20/6
13
A A
CN207
CN201CN202
2/2
1/4
CN204
CN304
CN305 CN105
CN302CN301
1/2
CN107
CN108
CN207to MAIN1/4 CN207(
MX12/6)
to IN8-CN403(
MX20/6)
CN106
to MAIN4/4 CN305
CN109 CN102CN104
CN103
CN101AC
POWER
SWITCH
POWER
TRANSFORMER
3/4
CN306
DCJK
MAIN DCJK
MAIN
4/4 MAIN 
						

							MX12/6
MX20/6
14
CIRCUIT BOARD LAYOUT
2/2(
MX20/6 model only)2/2
2/2 2/4
(
MX20/6 model only)1/2
1/41/2
3/4
4/4 IN8 DCJK
DCJK MAIN
IN8
MAINDCJK
MAIN
MAIN 
						

							MX12/6
MX20/6
15
DISASSEMBLY PROCEDURE
Fig.1 1. Panel Assembly
1-1. With the unit placed so that the rear panel faces
forward, remove the screws marked [30] and lift the
rear panel. The panel assembly can then be
removed. (Fig. 1)
[30]: Bind Head Tapping Screw-B  3.0 X 8 MFZN2BL (EP600190)  MX12/6: 18 screws  MX20/6: 19 screws
View A
[30] [30]Rear side
Rear side
[30] [30]
[30]
[30] [30]Top side
MX12/6
MX20/6Side view
[30] 
						

							MX12/6
MX20/6
16
Fig.2
[P50]:Hexagonal Button-P 3 X 25 MFZNBL (V3289800)
[P60]:Bonding Tapping Screw-B 3.0 X 8 MFZN2BL (VN413300)
[P70]:Bind Head Tapping Screw-B 3.0 X 8 MFZN2BL (EP600190)
2. MAIN 1/4 Circuit Board
2-1.Remove the panel assembly. (See Procedure 1.)
2-2.Remove the twelve (12) screws marked [P50A], the
twenty-three (23) screws marked [P60A], each knob
and hexagonal nut. The MAIN 1/4 circuit board can
then be removed. (Fig. 2)
3. MAIN 4/4 Circuit Board
3-1.Remove the panel assembly. (See Procedure 1.)
3-2.Pull off the MAIN 4/4 circuit board from the PCB
support. (Fig. 2)
4. MAIN 3/4 Circuit Board
4-1.Remove the panel assembly. (See Procedure 1.)
4-2. Remove the two (2) screws marked [P70]. The MAIN
3/4 circuit board can then be removed. (Fig. 2)
5. IN8 Circuit Board (for MX20/6 only)
5-1.Remove the panel assembly. (See Procedure 1.)
5-2.Remove the nine (9) screws marked [P50B], the
sixteen (16) screws marked [P60B], each knob and
hexagonal nut. The IN8 circuit board can then be
removed. (Fig. 2)
1/2 1/43/44/4
PCB support
[P70] [110] [130][P50A]
[120] [140] [170]
[160]
[150] [P50A]
[P50A]
[60]
[P60B]
[P50B]
[110] [100] [130] [120][130] [P60A] [P50A] [P50A] Hexagonal nut
Hexagonal nut
IN8 MAINMAINMAIN 
						

							MX12/6
MX20/6
17
Fig.3
[B70]:Bind Head Tapping Screw-B 3.0 X 8 MFZN2BL (EP600190)
[B90]:Bind Head Tapping Screw-B 3.0 X 8 MFZN2BL (EP600190)
[B100]:Bind Head Tapping Screw-B 3.0 X 8 MFZN2BL (EP600190)
6. DCJK 1/2 Circuit Board
6-1.Remove the panel assembly. (See Procedure 1.)
6-2. Remove the nine (9) screws marked [B90] and pull off
the DCJK 1/2 circuit board from the PCB support. (Fig. 3)
7. Heat Sink
7-1.Remove the panel assembly. (See Procedure 1.)
7-2. Remove the five (5) screws marked [B70]. The heat
sink can then be removed. (Fig. 3)
8. DCJK 2/2 Circuit Board
8-1.Remove the panel assembly. (See Procedure 1.)
8-2.Remove the screw marked [B100] and hexagonal
nut from the rear panel. The DCJK 2/2 circuit board
can then be removed. (Fig. 3)
9. MAIN 2/4 Circuit Board (for MX12/6 only)
9-1.Remove the panel assembly. (See Procedure 1.)
9-2.Remove the hexagonal nut. The MAIN 2/4 circuit
board can then be removed. (Fig. 3)
10. IN8 2/2 Circuit Board (for MX20/6 only)
10-1.Remove the panel assembly. (See Procedure 1.)
10-2. Remove the hexagonal nut. The IN8 2/2 circuit board
can then be removed. (Fig. 3)
Hexagonal nut
1/2[B90]
[B70]
2/2
(
MX20/6 only)
2/4
Hexagonal nut[B100]
2/2
Power
Transformer
DCJK
IN8MAIN DCJK 
						

							MX12/6
MX20/6
18
LSI PIN DESCRIPTION
PINNo.NAME I/O FUNCTION PIN
No.NAME I/O FUNCTION
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
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
5253
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100 ED2
ED3
ED4
ED5
ED6
ED7
VSS
VDD
CLKM0
CLKM1
TMS
TDI
TCK
CLKIN
VSS
VDD
CLKO
EA12/ED8
EA13/ED9
EA14/ED10
EA15/ED11
VSS
VDD
EA16/ED12
EA17/ED13
EA18/ES14
EA19/ED15
EA4/ED16
EA5/ED17
EA6/ED18
EA7/ED19
VSS
VDD
EA8/ED20
EA9/ED21
EA10/ED22
EA11/ED23
TEST0
TEST1
TEST2
TEST3
/BIO
/INT1
ARBC1
ARBC2
AX1
AX2
AX3
VSS
VDD
HX/SDA
/EMPTYAXLR2
AR1
AR2
HRBCK/SA0HR/SA1
HRS/SA2
VSS
VDD
HXBCK/SCLHXS/SA3
/CS/SA4
HBCKS/SA5I2CSEL
VSS
VDD
AXBC1
AXBC2
AXLR1
DIVS
/LAV
/LMV
/DRDY
EMU0
EMU1
TDO
DIV512
ARLR1
ARLR2
HDIR/SA6SEL5V3V/MUTE
/TRST
/RS
VSS
VDD
/IOE
/RAS/SRCS
/CAS/SROE
/ROME
/WE
EA0
EA1
EA2
EA3
VSS
VDD
ED0
ED1 I/O
I/O
I/O
I/O
I/O
I/O
S
S
I
I
I
I
I
I
S
S
O
I/O
I/O
I/O
I/O
S
S
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
S
S
I/O
I/O
I/O
I/O
I
I
I
I
I
I
I
I
O
O
O
S
S
I/O/Z
O/ZI
I
I
I
I
I
S
S
I
I
I
I
I
S
S
I
I
I
O
O
O
O/Z
I/O/Z
I/O/Z
O/Z
O
I
I
I
I
I
I
I
S
S
O
O
O
O
O
O
O
O
O
S
S
I/O
I/O
ZFX-2 (XY297A00)
CPU   MAIN: ICM01
External Memory and I/O Data Bus     
     
     
Ground     
Power Supply     
Clock Mode
TAP(Test Access Port) Mode Select     
TAP Data Input     
TAP Clock     
Master Clock     
Ground     
Power Supply     
Machine Clock Output     
External SRAM and ROM Address Bus/ 
External DRAM and I/O Data Bus          
     
Ground     
Power Supply     
External SRAM and ROM Address Bus/ 
External DRAM and I/O Data Bus     
          
     
External Memory Address Bus/ External I/O 
Data Bus     
     
Ground     
Power Supply     
External Memory Address Bus/ External I/O 
Data Bus     
          
     
Test Mode Control     
     
     
Separate Control Input     
Interrupt 1     
Audio Data Receive Unit 1 bit Clock     
Audio Data Receive Unit 2 bit Clock     
Audio Data Transmitt Unit 1 Data Output     
Audio Data Transmitt Unit 2 Data Output     
Audio Data Transmitt Unit 3 Data Output     
Ground     
Power Supply     
Host Interface Data Output/I2C Bus Data     
CMEM Update Buffer and HR Resistor Empty Flag Output
Audio Data Transmitt Unit 2/3 Left and 
Right Channel Frame Frequency Signal      
Audio Data Receive Unit 1 Data Input     
Audio Data Receive Unit 2 Data Input     
Host Interface Receive Clock / I2C Bus Address 0Host Interface Data Input/ I2C Bus Address 1 Host Interface Receive Data Frame 
Frequency Signal/ I2C Bus Address 2     
Ground     
Power Supply     
Host Interface Transmitt Clock/ I2C Bus ClockHost Interface Transmitt Data Frame 
Frequency Signal/ I2C Bus Address 3     
Host Interface Chip Select/ I2C Bus Address 4HRBCK/HXBCK Active Edge Select/ I2C Bus Address 5Host Interface Mode Select     
Ground     
Power Supply     
Audio Data Transmitt Unit 1 bit Clock     
Audio Data Transmitt Unit 2/3 bit Click     
Audio Data Transmitt Unit 1 Left and Right 
Channel Frame Frequency Signal     
Machine Clock Output then 8 min.     
Ruch ALU Overflow Frag Output     
Ruch MAC Overflow Frag Output     
Host Interface Transmitt Data Ready Frag OutputEmurator Interrupt 0     
Emurator Interrupt 1     
TAP(Test Access Port) Data Output     
Machine Clock then512 min.     
Audio Data Receive Unit 1 Left and Right 
Channel Frame Frequency Signal     
Audio Data Receive Unit 2 Left  and Right 
Channel Frame Frequency Signal     
Host Interface Data Format Select/ I2C Bus Address 6Input Level Control     
Mute Control     
TAP(Test Access Port) Reset     
Hardware Reset     
Ground     
Power Supply     
External I/O Enable     
External DRAM Low Address Strove/External 
SRAM Chip Select     
External DRAM Culumn Address Strove/External 
SRAM Output Enable     
External ROM Enable     
External Memory and I/O Wright Enable     
External Memory and I/O Address Bus          
        
Ground     
Power Supply     
External Memory and I/O Data Bus     
CLKM0
CLKM11
0
03
1
06
0
1PLL BYPASS
1
1 
						

							MX12/6
MX20/6
19
PIN
No.NAME I/O FUNCTION PIN
No.NAME I/O FUNCTION
1
2
3
4
5
6
7
8
9
10
11
12
13
1415
16
17
18
19
20
21
22
23
24
25
26
27
28 VINL
Vcc1
AGND1
VREFL
VREFR
VINR
CINPR
CINNR
CINNL
CINPL
VCOM
VOUTR
AGND2
Vcc2VOUTL
LRCIN
BCKIN
DIN
DOUT
XTI
XTO
CLKIO
VDD
DGND
FMT2
FMT1
FMT0
RSTB I
I
OO
I
I
I
O
I
O
I/O
I
I
I
I
PCM3001E (XY282A00)
ADAMAIN: ICM04
ADC Analog Input, Lch
ADC Analog Power Supply
ADC Analog GND
ADC Reference decouple, Lch
ADC Reference Decouple, Rch
ADC Analog Input, Rch
ADC Anti-areasing Filter Capacitor (+), Rch
ADC Anti-areasing Filter Capacitor (-), Rch
ADC Anti-areasing Filter Capacitior (-), Lch
ADC Anti-areasing Filter Capacitor (+), Rch
DAC Center Voltage Decouple
DAC Analog Output, Rch
DAC Analog GND
DAC Analog Power SupplyDAC Analog Output, Lch
Sampling Clock Input (fs)
Bit Clock Input
Audio Data Input
Audio Data Output
Crystal Oscillator Input, External System Clock InputCrystal Oscillator OutputCrystal Oscillator Buffer Output, External System Clock InputDigital Power Supply
Digital GND
Audio Data Format 2 (Pull up to 70k ohm typical)
Audio Data Format 1 (Pull up to 70k ohm typical)
Audio Data Format 0 (Pull up to 70k ohm typical)
Reset Input, Active L (Pull up to 70k ohm typical)
PINNo.NAME I/O FUNCTION PINNo.NAME I/O FUNCTION
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
2223
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44P12/ANI2
P13/ANI3
P14/ANI4
P15/ANI5
P16/ANI6
P17/ANI7
P72/SCK2/ASCK
P71/SO2/TXD
P70/SI2/RXD
P101/T16/T06
P100/T15/T05
P50
P51
P52
P53
P54
VSS
P55
P56
P57
P30
P31NC
P32
P33
P34
P35/PCL
P36/BUZ
P37
P00
P01/INTP1
P02/INTP2
P03/INTP3
NC
RESET
IC(VPP)
X2
X1
VDD
AVDD
AVREF
AVSS
P10/ANI0
P11/ANI1
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O-
I/O
I/O
I/O
I/O
I/O
I/O
I
I/O
I/O
I/O
-
I
-
-
I
-
-
I
-
I/O
I/O8 bits input/output port./A/D converter analog input.
8 bits input/output port./A/D converter analog input.
8 bits input/output port./A/D converter analog input.
8 bits input/output port./A/D converter analog input.
8 bits input/output port./A/D converter analog input.
8 bits input/output port./A/D converter analog input.
Port 7. 3 bits input/output port./Serial clock 
input/output of serial interface./Serial clock 
input for asynchronus serial interface.
Port 7. 3 bits input/output port./Serial data output for serial 
interface./Serial data output for asynchronus serial interface.
Port 7. 3 bits input/output port./Serial data input of serial 
interface./Serial data input for asynchronus serial interface
Port 10. 2 bits input/output port./External count 
clock input to 8 bits timer(TM6)./8 bits timer output.
Port 10. 2 bits input/output port./External count 
clock input to 8 bits timer(TM5)./8 bits timer output.
Port 5. 8 bits input/output port.
Port 5. 8 bits input/output port.
Port 5. 8 bits input/output port.
Port 5. 8 bits input/output port.
Port 5. 8 bits input/output port.
Port 5. 8 bits input/output port.
Port 5. 8 bits input/output port.
Port 5. 8 bits input/output port.
Port 5. 8 bits input/output port.
Port 3. 8 bits input/output port.
Port 3. 8 bits input/output port.Not connect.
Port 3. 8 bits input/output port.
Port 3. 8 bits input/output port.
Port 3. 8 bits input/output port.
Port 3. 8 bits input/output port./Clock output.
Port 3. 8 bits input/output port./Buzzer output.
Port 3. 8 bits input/output port.
Input only
4 bits input/output port./Effective edge (Rising 
edge, falling edge, both rising and falling 
edges) specifiable external interrupt input.
4 bits input/output port./Effective edge (Rising 
edge, falling edge, both rising and falling 
edges) specifiable external interrupt input.
4 bits input/output port./Effective edge (Rising 
edge, falling edge, both rising and falling 
edges) specifiable external interrupt input.
Not connect
System reset input
Internal connect
Main system clock oscillator Xtal
Main system clock oscillator Xtal
Power Supply
A/D Converter Analog Power Supply
A/D Converter Power Supply Input
A/D Converter ground
8 bits input/output port./A/D converter analog input.
8 bits input/output port./A/D converter analog input.
NTD78082(XZ312A00) MCU    MAIN: ICM03 
						

							MX12/6
MX20/6
20
IC BLOCK DIAGRAM
NJM4580L (XF195A00)
Operational AmplifierTC74HCU04AP (IG142200)
Inverter
M5229P (XG203A00)
7-SEG. GRAPHICBA682A (XS046A00)
LED Level Meter
1A2345678
IN V+IN
OUT
AAA+V IN+IN
OUT
BBB
+B+
1A2345678
IN V+IN
OUT
AAA+V IN+IN
OUT
BBB
+B+
1A2345678
IN V+IN
OUT
AAA+V IN+IN
OUT
BBB
+B+
1A2345678
IN V+IN
OUT
AAA+V IN+IN
OUT
BBB
+B+
(MX12/6 MAIN, MA20/6 MAIN: IC101,IC201,IC301,
 IC401, IC501, IC601, IC701, IC801, ICD02, ICE02, 
 ICF04, ICG04, ICH04, ICI31, ICI61) (MX12/6 MAIN, MA20/6 MAIN: ICB01, ICB51, ICM06)
(MX12/6 MAIN, MA20/6 MAIN: ICM05)(MX12/6 MAIN, MA20/6 MAIN: ICF03, ICG03) (MX12/6 MAIN, MA20/6 MAIN: ICJ01, ICJ51)
(MA20/6 IN8: IC101, IC201, IC301, IC401, IC501, 
 IC601, IC701, IC801,) 
NJM2068L-D (XM356A00)
Operational Amplifier NJM4558L-D (XQ212A00)
Operational Amplifier
NJM4556AL (XP844A00)
Operational Amplifier
(MX12/6 MAIN, MA20/6 MAIN:  IC102, IC103, IC302, 
 IC303, IC502, IC503, IC702, IC703, IC901, IC904, 
 ICA01, ICA02, ICA03, ICD01, ICD03, ICE01, ICF02, 
 ICG01, ICH01, ICI01) 
 
(MX12/6 MAIN, MA20/6 MAIN:  ICJ02)(MA20/6 IN8:  IC101, IC103, IC302, IC303, IC502, 
 IC503, IC702, IC703)
1
2
3
4
5
6
7
8
9
10
11 1213 14
15 1617 181920IN1
IN2
IN3
IN4
IN5 NF1
NF2
NF3
NF4
NF5-Vcc
GND
+Vcc
OUTPUT
INVERTED
INPUT
NON-INVERTED
INPUT
NF7
NF6 IN7
IN6-+
-+
-+
-+
-+-+
-+
-+
47k
560
47k
560
47k
560
47k
560
47k47k
47k
47k 56010k 10k
Current setting
Input
Time constant for lighting
LED drive output
LED drive output
LED drive output
LED drive output
GNDVcc
LED drive output
LED drive output
LED drive output
LED drive output
LED drive output
LED drive output
LED drive output
LED drive outputN.C.1
2
3
4
5
6
7
8
910 11 12 13 14 151617 18
1
2
3
4
5
6
7 1A
1Y
2A
2Y
3A
3Y
GND
14
13
12
11
10
9
8V
cc
6A
6Y
5A
5Y
4A
4Y