Yamaha YST-SW005, Service Manual

Page: 9 / 16

A
1
2
3
4
5
6
7
8
9
B C D E F G H I J K L
YST-SW005
★ All voltage are measured with a 10M
Ω
/V DC electric volt
meter.
★ Components having special characteristics are marked
s and must be replaced with parts having specifications
equal to those originally installed.
★
Schematic diagram is subject to change without notice.
● 電圧は、内部抵抗10MΩの電圧計で測定したものです。
●
s 印のある部品は、安全性確保部品を示しています。部
品の交換が必要な場合は、パーツリストに記載されてい
る部品を使用してください。
● 本回路図は標準回路図です。改良のため予告なく変更す
ることがございます。
8
SCHEMATIC DIAGRAM
IC9 : NJM78L08AV
Voltage Regulator IC5 : KIA555P
Protect
IC3 :
µ
PC1237HA
Protect
IC2 : STK404-050AF
AF Power Amp.
IC1, 4, 7, 10 : NJM4558D
OP Amp.
BC
E
BC
E
PIN CONNECTION DIAGRAM OF TRANSISTORS, DIODES AND ICS.
2SD2531
2SB1642 2SK304 2SC4688 RBV-402 S1NB20 2SC1815
2SA1015
2SC2240
E
C B
–
+
~
+
~
–
1N4148
MTZ15C
MTZJ24B
MTZJ12C
Anode
Cathode
µ
PC1237HA NJM4558D
KIA555P NJM78L08A STK404-050AF
1
8
OUT
COM
IN
S
G D
1
10
V IN
V OUT
GND
GND
6 4 1 2 3
TRIGGER
OUT
RESET
REFERENCE
VOL
T
AGE
THRESHOLD
DISCHARGE
VCC
7
8
+
–
FLIP-
FLOP
+
–
5
R R R
1
2
5 4 3
7 8
6
Overload
detect
Mid-point
potential
detect
Flip flop
circuit
Vcc on
mute
AC OFF
detect
Latch / automatic
return select
Relay
drive
circuit
GND
Vcc
1 2 3 4 5 6 7 8 9 10
R1
R4
R5
C1
C2
D1
TR3
TR5
R3 R6
TR4
SUB
R2
TR1 TR2
TR6
TR7
TR8
– + – +
OUT1
–IN1
+IN1
–Vcc
+Vcc
OUT2
–IN2
+IN2
1
2
3
4
8
7
6
5
1
4 8
0
0
0
0
0
0
14.3
-14.3
0
0
0
0
0
0
0
0
0
0
0
0 0.5
0.8
0
0
0
0
0
0
0
0
0
0 0 0
13.2
-13.2
0
0
13.2
-13.2
-1.5
0
0
0.1 0.1
0
-32.5
14.3
1.2
-1.2
-33.2
33.2
0
0 0
2.9
0
0.8 2.2
3.5
3.9 6.6 7.9 5.3 7.9
0
0.1
0.6
0
33.2
A
C25.2
14.8
-14.8
-33.2
13.4
13.4
13.4 7.9
7.9
7.9
3.9
3.9
3.9 3.9
3.9
3.9
13.4
0
0
14.3
14.3
-14.3
-14.3
A
C12.2
A
C25.2
R, T, K models
POWER SUPPLY
AUTO POWER ON/OFF CIRCUIT
PROTECTION
J, U, C, A, B, G models
WH
RE
BE
BE YE
YE YE
RE RE
WH
MAIN (2) MAIN (1)
MAIN (3)
MAIN (4)
MAIN (5)
MAIN (6)
LIMITTER
POWER AMP.