Yamaha PORTATONE KB-280 Service Manual page 46

A B
KB-280 BLOCK DIAGRAM
TOUCH RESPONSE
Keybord 61KEY (16N)
61L 61H
(C1~B3) (C4~C6)
PC0-5,PD0-5 PC0-5,PD0-5
SW1-36
SW37-61
CN2 (5P) CN1 (12P)
CN5 (7P)
CN402 (7P) CN403 (5P)
CN401 (12P)
DMLCD
+3.3D
DECODER DECODER LED DRIVER
16 16
74LV138A
VCC VCC 74LV138A
PF0
TR705
IC401 (16P) IC402 (16P)
117
VDD
+2.5V
15,46,89,119
IOVDD
24,47,66,90,120
+3.3D
37,121
CPU
+5D
SWL01(T)
IC302 (5P)
YMW767-VTZ
5
32
RESET
4 16 40
+3.6V 50ms 42~44
IC301 (128P)
41
X301
16.9344MHz 12
Crystal SMD-49
13
FTolerance 100PPM
32,34~36 67,68,123
IRQO
TXDO
MA01-22
RXDO
MD00-15
PC7
MA01-22
MD00-15
128M ROM
PROG./
WAVE
IC201
(48P)
VCC
36,37
RESET
28CA1-2001002836
C D
PB PNL
PNL
(AMJK 6/6) (PN 4/6)
(PN 2/6)
VR751
PA6
SW771
PA6
PB6
PB6
LED
PITCH BEND
LD753
1PCS
AIN1
+3.3D
+5D
LED DRIVER
PA0-PA7
VDD
TR701~704
PA0-PA7
RS, ENB
36,38
+6A
REGULATOR +5V
IC101 (3P)
+5D
+5A
REGULATOR +3.3V
PB0-PB7
PA0-PA7
IC102 (3P)
+3.3D
RS, ENB
REGULATOR +2.5V
IC103 (3P)
+2.5D
+5A +6A
14
PC7
5
11 L
DAC
BUFFER/
2,3
SD0 12
3
24bit
LPF
1,2,4 9 R
BCLK 5,6
10 IC502(8P)
IC501
WCLK
(16P)
SYSCK
fC=27KHz
+3.3D
/UWR, /LWR, /CAS
2
ADC
BCLK AIN1
7
WCLK 8bit
4 AIN4
1,10
IC801
SDI
9
(10P)
MA01-18 MA01-09
MD00-15 MD00-15
+3.3D
FLASH DRAM 1,2,4 14
/UCAS
OR
/LCAS
ROM 4M
8,11
74LV32A
4M
31,32
IC206 IC204
IC207 (14P)
(48P) (44P)
12 VCC VCC
37 1,6,22
+3.3D
E
PA4
PA4,PA6,PA7,PC6
SW MATRIX
LED
( SW 25PCS )
PB0-PB7
LD752
SW746~770
1PCS
CN774 (16P)
CN703 (16P)
LED
PB0-PB7
PA0-PA7
33 LCD
LCD
DRIVER
DISPLAY
IC601
(80P)
BACK LIGHT
LED:2PCS( Blue )
+6A
+V
L
R
AM (AMJK 4/6)
VR551
8
MASTER
VOLUME
L
1
A5K
R
7
MIDI
SUSTAIN
OUT IN
JK851
JK852
JK853
I/F
DGND
IC851,TR851,852
RXD0
TXD0
PC7
IRQ0
R+
R-
MIDI (AMJK 2/6)
F G
PNR
SW MATRIX
(PN 1/6)
PA0
( SW 39PCS )
PNR
SW701~739
(PN 3/6)
LED
LD751
PB0-PB5
PB0-PB5
1PCS
PA6 PA6
LED
CN771 (16P)
AM (AMJK 1/6)
TWL
REGULATOR +6V
(PN 5/6,6/6)
IC151 (3P)
+V
14
L-
13
L+
11
L
1
POWER AMP
6W X 2
R R+
6 8
BTL R-
9
LA4625
IC551 (14P)
AGND
R-
R+
AM (AMJK 5/6)
SW151
STANDBY/ON
DGND
+
TWEETER R
-
TWR
(PN 5/6,6/6)
WOOFER R
4 12cm
KB-280 BLOCK DIAGRAM
H
KB-280
1
SW MATRIX
( SW 6PCS )
SW740~745
2
+
WOOFER L
-
4 12cm
-
TWEETER L
+ 3
L+
L+
PHONES /
R+
OUTPUT
R+
JK551
DC IN 12V
AC adaptor
PA-5C/PA-5D/PA-51
4
JK151
-
BATTERY
+
1.5V x 6
EXPRESSION
JK856
5
6