Service manual

FO-4700U
FO-47UC
IC18: VHiHD74LS374F(HD74LS374)
8 – 8
OE
CK
Q
D
2
3
4
OE
CK
Q
D
5
6
1
7
8
9
10
OE
CK
Q
D
OE
CK
Q
D
OE
CK
Q
D
19
18
17
16
15
20
14
13
12
11
OE
CK
Q
D
OE
CK
Q
D
OE
CK
Q
D
Output
Control
1Q
1D
2D
2Q
3Q
3D
4D
4Q
GND Cloc
k
5Q
5D
6D
6Q
7Q
7D
8D
8Q
VCC
20 19 18 17 16 15
123456
IG 1A1 2Y4 1A2 2Y3 1A3
VCC 2G 1Y1 2A4 1Y2 2A3
14
1Y3
7
2Y2
8
1A4
9
2Y1
10
GND
13
2A2
12
1Y4
11
2A1
IC20: VHiHD74LS244F(HD74LS244)
IC30: VHiSM8578BV-1(SM8578BV)
INTN
XTN
XT
VSS
1
4
8
5
VDD
DATA
CLK
CE
8 7 5 8 B
IC15: VHiHD74LV08T1(74LV08A)
14 13 12 11 10 9
123456
1A 1B 1Y 2A 2B 2Y
VCC 4B 4A 4Y 3B 3A
8
3Y
7
GND
IC19: VHiHD74HC74FM(74HC74)
INPUT
Q
CLR
PR
CK
D
Q
Q
CK
Q
PR
CLR
D
VCC
2 CLR
2D
2CK
2PR
2Q
2Q
GND
1 CLR
1D
1CK
1PR
1Q
1Q
D
X
X
X
H
L
X
OUTPUT
Q
H
L
H*
H
L
Q
Q
H*
L
H
L
CLK
X
X
X
R
H
L
L
H
H
H
L
H
PR
L
H
H
H
NO Change
H:High L:Low X:H or L
1234567
91011121314 8
IC35: VHi74VHC393FT(74VHC393)
14 13 12 11 10 9
123456
1A 1CLEAR 1QA 1QB 1QC 1QD
VCC 2A 2CLEAR 2QA 2QB 2QC
8
2QD
7
GND
QA QB QC QD
A
QA QB QC QD
A
CLR
OUTPUTS
OUTPUTS
CLR