Yamaha YHT-S300 Service Manual page 84

A B C
SR-300/NS-BR300/NS-P705/NS-B380
POWER 2/2
1
2
3
4
3.3 3.3
-30.1
-29.8 -29.8
5
3.4 3.4
3.4
6
0
0 0
3.3
2.0 0
7
STATUS
indicator
0
Key destination for A/D port
Key input (A/D) pull-up resistance 10 k-ohms
8
Ohm 0 + 6.8 k + 22 k
V 0 – 0.2 1.2 – 1.5 2.3 – 2.6
A/D value
0 – 15 95 – 115 180 – 200
(3.3 V=255)
KEY1 (127 pin) VOLUME + VOLUME - INPUT
9
POWER (2)
10
84
D E F
-32.8
-17.4
-8.2
-30.1
-28.1
FL DRIVER
-31.9
-15.4
IC851
-12.0
-17.4
-11.8
-19.4
-30.1
-11.7
-30.1
-30.1
3.4 3.4
Page 82 B6
to MAIN_CB307
G H I
-28.2
-28.2
-11.8
-17.3
-15.5
-11.9
-11.2
-11.8
3.3
1.6
-32.2
1.6 -17.3
0 -32.2
0.2
0 -17.3
3.3
-24.2
3.4
-32.2 -17.3
3.4
0 -17.3
0 0
3.4 0 3.3
Page 82 B2
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J K L
IC851: M66003-0131FP-R
18 digit 5 x 7 segment VFD controller/driver
CS 2 Serial
receive
SCK 3
SDAT A A A T T 4 circuit
XIN 7
Clock
generator
XOUT 6
RESET 1
Vcc1 8
Vcc2 18
12.2 Vss 5
Vp 64
-0.5
0
0
-0.5
12.2
SPEAKERS
POWER (3)
★ All voltages are measured with a 10MΩ/V DC electronic voltmeter.
● 電圧は、内部抵抗 10MΩの電圧計で測定したものです。
★ Components having special characteristics are marked
and must be replaced ● 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、
with parts having specifications equal to those originally installed. 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。
★ Schematic diagram is subject to change without notice.
● 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。
M N
Display code
CGROM
RAM
(35-bit x 166) 44 SEG00
(8-bit x 60)
Segment 19 SEG25
Code
write output
17 SEG26
circuit
CGROM
dot data 9 SEG34
data write (35-bit x 16)
Code/
command
control 45 SEG35
circuit
DIG11/
52
SEG42
DIG12/
51
SEG41
Segment/
code
DIG13/
select Digit 50
SEG40
select/
DIG14/
49
output SEG39
timing Display
clock circuit DIG15/
controller scan pulse 48
SEG38
DIG16/
47
SEG37
DIG17/
46
SEG36
63 DIG00
Digit
output
circuit
53 DIG10
Page 80 K6
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