![background image](http://html.mh-extra.com/html/icom/ic-7400/ic-7400_service-manual_612265084.webp)
12 - 1
SECTION 12
VOLTAGE DIAGRAM
TMS320VC33PGE120
IC301
1
A20
2
VSS
3
A19
4
A18
5
A17
6
DVDD
7
A16
8
A15
9
VSS
10
A14
11
A13
12
CVDD
13
A12
14
A11
15
DVDD
16
A10
17
A9
18
VSS
19
A8
20
A7
21
A6
22
A5
23
DVDD
24
A4
25
VSS
26
A3
27
A2
28
CVDD
29
A1
30
A0
31
DVDD
32
PAGE3
33
PAGE2
34
VSS
35
PAGE1
36
PAGE0
37
DVDD
38
H1
39
H3
40
VSS
41
STRB
42
R/W
43
DVDD
44
IACK
45
RDY
46
CVDD
47
HOLD
48
HOLDA
49
VSS
50
D31
51
D30
52
D29
53
DVDD
54
D28
55
D27
56
VSS
57
D26
58
D25
59
D24
60
DVDD
61
D23
62
D22
63
VSS
64
D21
65
D20
66
CVDD
67
D19
68
D18
69
DVDD
70
D17
71
D16
72
VSS
73
D15
74
D14
75
D13
76
D12
77
DVDD
78
D11
79
D10
80
VSS
81
D9
82
D8
83
CVDD
84
D7
85
D6
86
DVDD
87
D5
88
D4
89
VSS
90
D3
91
D2
92
D1
93
D0
94
DVDD
95
EMU1
96
EMU0
97
VSS
98
TCK
99
TDO
100
TDI
101
CVDD
102
TMS
103
TRST
104
DR0
105
VSS
106
FER0
107
CLKR0
DVDD
109
CLKX0
110
FSX0
111
DX0
112
VSS
113
TCLK1
114
TCLK0
115
DVDD
116
XF1
117
XF0
118
VSS
119
INT3
120
INT2
121
INT1
122
INT0
123
124
EDGEMODE
125
MCBL/MP
126
VSS
127
RESET
128
SHZ
129
130
EXTCLK
131
PLLVDD
132
XOUT
133
XIN
134
PLLVSS
135
CLKMD1
136
CLKMD0
137
CVDD
138
RSV1
139
RSV0
140
VSS
141
A23
142
A22
143
DVDD
144
A21
R321
4.7k
R320
4.7k
C325
0.0047
C324
0.0047
C323
0.1
C322
0.0047
C321
0.1
C320
0.1
R317
10k
R318
10k
C313
0.1
C314
0.0047
C315
0.1
C316
0.0047
C317
0.1
C318
0.0047
C319
0.0047
CP306
CP307
CP308
C301
0.0047
C302
0.0047
C304
0.0047
0.1
C306
C303
0.1
C305
0.1
R303
2.2k
R304
2.2k
R305
10k
R306
10k
R307
10k
R308
10k
R309
10k
R310
10k
R311
10k
R312
10k
R313
10k
C307
0.1
C308
0.1
C309
0.0047
C311
0.0047
C312
0.1
W308
W309
W1
W501
W310
CP300
IC403
SN74AHCT374PW
1
O-CTRL
2
1Q
3
1D
4
2D
5
2Q
6
3Q
7
3D
8
4D
9
4Q
10
GND
11
CLK
12
5Q
13
5D
14
6D
15
6Q
16
7Q
17
7D
18
8D
19
8Q
20
VCC
IC404
SN74AHCT374PW
1
O-CTRL
2
1Q
3
1D
4
2D
5
2Q
6
3Q
7
3D
8
4D
9
4Q
10
GND
11
CLK
12
5Q
13
5D
14
6D
15
6Q
16
7Q
17
7D
18
8D
19
8Q
20
VCC
L404
2.2
µ
L403
2.2
µ
C404
0.0047
C403
0.0047
SN74AHC595PW
IC401
1
QB
2
QC
3
QD
4
QE
5
QF
6
QG
7
QH
8
GND
9
QH’
10
SCLR
11
SCK
12
RCK
13
G
14
SI
15
QA
16
VCC
C401
0.0047
L401
2.2
µ
SN74AHC74PW
IC406
V+
14
GND
7
SN74AHC74PW
IC406
1
CLK
2
D
3
CK
4
PR
5
Q
6
Q
SN74AHC74PW
IC406
13
CLK
12
D
11
CK
10
PR
9
Q
8
Q
CP302
CP305
CP304
CP303
R322
47
L405
2.2
µ
C406
0.0047
L406
2.2
µ
µ
PC4570G2
IC701b
6
5
7
C752
100p
C751
270p
R753
3.3k
R754
6.8k
R756
6.8k
R755
3.3k
R752
4.7k
R751
4.7k
C755
100p
C758
10
µ
PC4570G2
IC701a
2
3
1
3.3k
R705
270p
C701
6.8k
R706
100p
C702
6.8k
R704
4.7k
R701
4.7k
R702
3.3k
R703
100p
C705
10
C708
µ
PC4570G2
IC701
V+
8
GND
4
C703
0.1
C901
0.001
C704
10
L701
100
µ
BA15532F
IC651a
2
3
1
BA15532F
IC651b
6
5
7
R656
4.7k
R657
4.7k
R655
4.7k
R651
390
R652
390
R658
4.7k
R653
1k
R654
1k
C654
0.1
C651
0.0015
BA15532F
IC651
V+
8
GND
4
C652
0.1
C653
10
L651
100
µ
C655
1
4.7k
R610
4.7k
R609
4.7k
R608
390
R603
1
C606
10
C604
100
µ
L601
BA15532F
IC601
V+
8
GND
4
0.1
C605
0.1
C603
1k
R606
390
R604
0.0015
C602
BA15532F
IC601b
6
5
7
1k
R605
BA15532F
IC601a
2
3
1
4.7k
R607
R601
1.2k
R602
4.7k
C601
10
AK4528VF
IC501
1
VCOM
2
AINR+
3
AINR-
4
AINL+
5
AINL-
6
VREF
7
AGND
8
VA
9
P/S
10
MCLK
11
LRCK
12
BICK
13
SDTO
14
SDTI
15
CDTI
16
CCLK
17
CSN
18
DFS
19
PDN
20
DEM0
21
DEM1
22
VT
23
VD
24
DGND
25
AOUTL-
26
AOUTL+
27
AOUTR-
28
AOUTR+
IC801
SN74AHC244PW
1
ENA
2
A1
3
YB4
4
A2
5
YB3
6
A3
7
YB2
8
A4
9
YB1
10
GND
11
B1
12
YA4
13
B2
14
YA3
15
B3
16
YA2
17
B4
18
YA1
19
ENB
20
VCC
X51
CR-709
R51
1M
C52
5p
C53
5p
L52
1.0
µ
C54
0.01
TC7WHU04FU
IC51
1
2
3
4
5
6
7
8
CP301
TC7WHU04FU
IC1
1
2
3
4
5
6
7
8
33p
C2
47p
C6
10p
C8
0.001
C802
5p
C9
CR-628
X1
33p
C3
1M
R1
L51
2.2
µ
L1
2.2
µ
EP2
C1
0.0047
C51
0.0047
IC101
SN74HCT244APW
1
ENA
2
A1
3
YB4
4
A2
5
YB3
6
A3
7
YB2
8
A4
9
YB1
10
GND
11
B1
12
YA4
13
B2
14
YA3
15
B3
16
YA2
17
B4
18
YA1
19
ENB
20
VCC
SN74AHC74PW
IC3
1
CLK
2
D
3
CK
4
PR
5
Q
6
Q
SN74AHC74PW
IC3
13
CLK
12
D
11
CK
10
PR
9
Q
8
Q
SN74AHC74PW
IC4
1
CLK
2
D
3
CK
4
PR
5
Q
6
Q
SN74AHC74PW
IC4
13
CLK
12
D
11
CK
10
PR
9
Q
8
Q
SN74AHC74PW
IC3
V+
14
GND
7
SN74AHC74PW
IC4
V+
14
GND
7
L2
2.2
µ
C4
0.0047
L3
2.2
µ
C7
0.1
C201
0.1
TC7SH04FU
IC202
1
2
3
4
5
C202
0.1
W202
W302
W303
C101
0.1
C407
0.001
L101
2.2
µ
L102
2.2
µ
C103
0.1
C102
10
C104
10
L801
2.2
µ
R801
100k
R201 47k
R802
100k
C801
0.0047
R803
100k
R804
100k
R805
100k
R323
10k
R324
10k
W311
W312
C508
0.1
C507
0.1
C511
22p
C506
22
C504
2.2
C505
0.1
R501
4.7
C509
0.1
C510
22
L502
2.2
µ
L501
2.2
µ
C154
0.1
C155
0.1
C156
0.1
C157
10
R151
68
TK11250BM
IC171
CONT
1
GND
2
N.BYPASS
3
VOUT
4
GND
5
VIN
6
0.1
C173
15
R171
10
C174
0.1
C171
0.1
C172
C162
0.1
C163
0.1
C161
22
C164
10
TK11218BM
IC152
CONT
1
GND
2
N.BYPASS
3
VOUT
4
GND
5
VIN
6
R161
33
R162
27
L301
2.2
µ
L302
2.2
µ
W201
J901
W901
D901
MA729
R904
10k
2
30
29
1
1
21
22
2
R903
10k
R902
10k
R901
10k
R905
10k
R906
10k
M29W102BB
IC201
A9
1
A10
2
A11
3
A12
4
A13
5
A14
6
A15
7
NC
8
W
9
VCC
10
RP
11
E
12
DQ15
13
DQ14
14
DQ13
15
DQ12
16
DQ11
17
DQ10
18
DQ9
19
DQ8
20
VSS
21
DQ7
22
DQ6
23
DQ5
24
DQ4
25
DQ3
26
DQ2
27
DQ1
28
DQ0
29
G
30
A0
31
A1
32
A2
33
A3
34
A4
35
A5
36
A6
37
A7
38
A8
39
VSS
40
BA033FP
IC161
I
O
G
R52
100
R2
470
W151
W902
IC405
BU4021BF
1
H
2
QF
3
QH
4
D
5
C
6
B
7
A
8
VSS
9
P/S
10
CLK
11
SER
12
QG
13
E
14
F
15
G
16
VDD
C405
0.0047
C408
0.001
CP1
C.P8S
BU9480F
IC102
OUTR
1
REF
2
GND
3
OUTL
4
LRCLK
5
SDATA
6
BCLK
7
VCC
8
R328
10k
R327
10k
R326
10k
R325
10k
R611
5.6k
R659
5.6k
R707
1k
R708
1k
C706
0.1
C707
100
C756
0.1
C757
100
R758
1k
R3
47k
R757
1k
C175
10
C158
10
J902
W171
W152
W3
W2
CP351
CP352
CP353
CP354
CP355
CP356
CP357
CP358
CP359
CP360
CP801
CP802
CP803
CP804
CP805
CP806
CP807
CP808
CP809
CP810
W951
W952
CP811
CP812
Q302
DTC144EU
Q301
DTC144EU
D15
D00
D01
D02
D03
D04
D05
D06
D07
D10
D11
D12
D13
D14
A00
A01
A02
A03
A05
A06
A07
A08
A09
A10
A11
A12
A13
A14
A15
A04
D07
D06
D05
D04
D03
D02
D01
D00
OUT1
OUT2
OUT3
OUT4
D12
D13
D14
D15
D11
D10
D09
D08
OUT5
OUT6
OUT7
OUT8
D07
D01
D02
D05
D00
D04
D03
D06
DI
ROO
RQI
IBS
OBS
D15
D14
D13
D12
D11
D10
D09
D08
D01
D02
D03
D04
D05
D06
D07
A00
A01
A02
A03
A04
A05
A06
A07
A08
A09
A10
A11
A12
A14
A15
A13
OBSY
IBSY
OBS
IBS
FDIS
FINT
GND
GND
to MAIN
unit J1001
to MAIN
unit J1000
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
AGC2
AGC1
GND1
GND1
GND1
GND1
GND1
KEYIN
OUT7
OUT5
OUT3
OUT1
OBSY
GND1
GND1
GND1
GND1
GND1
DRES
192K
IBSY
DO
OUT2
OUT4
OUT6
OUT8
UNLK
DI
DI
STBO
STBO
CK
RQI
RQO
D09
D08
D00
D0G
D0F
D0E
D0G
D0F
D0E
DO
STBO
CK
D0H
D0A
D0B
D0C
D0D
D0H
D0D
D0C
D0B
D0A
FSTB
FDAT
8V
8V
8V
DSPO2
DSPO1
DSPI1
DSPI2
TRST
TCK
EMU0
TMS
TDO
TDI
EMU1
PD
FCK
DRES
DRES
GND1
GND1
FOK
FBSY
KEYIN
UNLK
FENA
108
J1000
J1001
2
1
22
21
1
2
29
30
DSP UNIT
CVDD
DVDD
DGND
DSKY
NC
VSOL
TOFF
CTFL
DGND
DRBY
DROR
DGND
DCK
DROW
DGND
DGND
DRES
DGND
DSST
NC
DCBY
RTDT
NSOL
DGND
DSTR
DDTR
DGND
DDTW
DWBY
DGND
NC
DGND
GND
GND
DRAF
GND
MONI
GND
8V
GND
GND
GND
DRIF
DTIF
GND
GND
GND
DAGC
GND
8V
GND
DTAF
GND
GND
MAIN UNIT (1)
XP4312
Q201
3
2
6
5
1
4
MEASUREMENT CONDITIONS
frequency : 14.1MHz USB
SG input : off
Voltage at rx
Digital tester
Oxilloscope(20MHz)
2.3V
#01:40ns
#02:80ns
0.9V
0V
2.6V
#01:80ns
#02:160ns
0.4V
3.3V
0V
0V
#01:5.2
µ
s
#02:10.4
µ
s
AGC1 DSP02
3.3V
0V
#01:10.4
µ
s
#02:20.8
µ
s
1.7V
1.5V
0V
AGC1 DSP02
AGC1 DSP02
DSP02
DSP02
DSP02
1.82V
3.36V
7.61V
4.07V
A
B
C
C
B
A
2.83V
3.93V
5.01V
6.84V
2.83V
2.83V
2.83V
2.5V
3.84V
3.84V
2.5V
2.49V
2.49V
12-1 DSP UNIT
Summary of Contents for IC-7400
Page 1: ...HF VHF TRANSCEIVER i7400 SERVICE MANUAL ...
Page 63: ...to S LOGIC board J303 DS1002 9 2 DISPLAY BOARD TOP VIEW 9 3 for free by RadioAmateur eu ...
Page 72: ...9 12 1 9 18 10 BOTTOM VIEW RF UNIT for free by RadioAmateur eu ...
Page 74: ... BOTTOM VIEW CTRL UNIT 9 14 for free by RadioAmateur eu ...
Page 76: ... BOTTOM VIEW TUNER UNIT 9 16 for free by RadioAmateur eu ...
Page 78: ...9 18 BOTTOM VIEW PA UNIT for free by RadioAmateur eu ...
Page 92: ...1 1 32 Kamiminami Hirano ku Osaka 547 0003 Japan S 13811HZ C2 2002 Icom Inc ...