![background image](http://html.mh-extra.com/html/icom/ic-m21/ic-m21_service-manual_612741030.webp)
5V
TEMPV
TEMPV
F
FCON
UNLK
UNLK
PLST
PLST
SCK
SDATA
DAST
SCK
SDATA
DAST
SCK
SDATA
R192
390
DET
C191
0.01
C192
10
R194
100 k
MODC
PCON
MODC
PCON
BEEP
VOLO
AFV
CPU5V
5V
5V
+
5V
Q250
UN911H
PTT
PTT
5V
C254
0.01
IC260
TC4W66F
R258
4.7 k
R300
20 k
ATIS8
ATIS7
ATIS6
ATIS5
ATIS4
ATIS3
ATIS2
ATIS1
R302
20 k
DETM
DETM
MICM
AFOUT
R304
20 k
SPO
SPO
J251
BM02B-ASRS-TF
1
2
GND
R306
20 k
R308
20 k
D350
DA204U
Q350
DTC144TU
R353
1 k
CPU5V
R351
1 k
R310
20 k
R312
20 k
R314
20 k
MICM
DETIN
DETO
DET
R253
2.2 k
5V
IC200
NJM2902V
1
2
3
4
5
6
7
14
13
12
11
10
9
8
8
7
6
5
1
2
3
4
5V
DETM
MICO
MICIN
R255
150 k
R271
56 k
R272
120 k
C265
150 P
R273
22 k
R279
1.5 k
R276
180 k
C263
0.01
R288
220 k
R281
33 k
Q280
2SC4213 B
R286
10 k
IC280
TA7368F
AFOUT
R284
10
R350
470 k
CPU5V
IC340
HN58X2416TI
TEMPV
R346
10
CPU5V
CPU5V
CPU5V
IC360
HD6433844RA60H
CPU5V
CPU5V
CPU5V
LCDC1
LCDC2
SCK
R362 1 k
PLST
SDATA
X360
CR-610
R365 1 M
IVOLM
CLOUT
CLIN
AFVS
R5VS
R372
100 k
R373
100 k
R374
68 k
R371
100 k
BEEP
CP360
UNLK
TDEC
R360 1 k
R361 1 k
R363 1 k
R364 1 k
DAST
R366 220 k
R367 120 k
SCK
PLST
SDATA
DAST
CLIN
CLIN
RESET
BTYPE
CHEXT
WXTV
R343
10 k
IC341
S-80942ANMP-DD6
PTT
NC
VCC
NC
VIN
RIPPLE
10
9
8
7
6
POUT
PWGND
PREGND
PHASE
NF
1
2
3
4
5
R289
150 k
BEEP
BEEP
NOISV
NOISV
RSSIV
RSSIV
BEEP
NOISV
RSSIV
NOISV
RSSIV
VOLO
C267
0.22
WXTV
R263
100 k
C376
0.1
MIC
CP253
CP254
J250
HSJ1594-010050
CP255
CP252
CP251
CLONE
SPO
AFOUT
MIC
GND
CLONE
CLONE
SPO
AFOUT
MIC
GND
MC250
PTTSW
S250
R251
470
C250
0.01
R250
100 k
C251
10
R260
12 k
C260
10
R261
3.9 k
C261
0.1
R256
18 k
R202
100 k
R204
4.7 k
R205
27 k
R376
100 k
C200
0.01
C257
0.01
C262
0.01
R264
100 k
R265
100 k
C300
0.0033
R301
10 k
R303
10 k
R305
10 k
R307
10 k
R309
10 k
R311
10 k
R313
10 k
R315
20 k
R257
4.7 k
C264
0.0056
C379
56 P
R277
100 k
R274
390 k
R282
10 k
C281
0.47
C285
0.1
C282
10
C289
220
C350
0.01
CP350
CP353
CP351
CP354
CP352
C361
0.047
C363
0.047
C364
0.047
R345
470 k
C360
0.01
R341
10 k
R340
10 k
ESCK
ESDA
C342
100
C341
0.027
C365
0.047
C366
0.047
C367
0.033
C368
0.047
CP355
C288
0.047
R283
33
C286
10
C287
150 P
TDETV
BATTV
BTYPE
C283
0.1
C284
0.001
C280
0.47
R275
10 k
C205
0.018
R214
15 k
C206
0.001
C207
0.1
C378
0.0047
C377
820 P
C266
0.027
R278
1 k
R352
15 k
C351
47 P
C352
47 P
CLOUT
C340
0.01
CLIN
IVOLM
R262
1.8 k
R375
4.7 k
CP250
C252
0.001
R252
33 k
UP
S320
S323
CHWX
SQL
SCAN
DOWN
16CH
S321
S322
S324
S325
S326
DW
HL
S327
R201
15 k
R203
1.2 M
R207
27 k
C202
0.1
R206
18 k
R377
82 k
R378
82 k
R379
82 k
A0
A1
A2
VSS
8
7
6
5
VCC
WP
SCL
SDA
1
2
3
4
OUT
VDD
VSS
CD
NC
1
2
3
5
4
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
P91/SEG34
P92/SEG35
P93/SEG36
P94/SEG37/M
P95/SEG38/DO
P96/SEG39/CL2
P97/SEG40/CL1
P40/SCK32
P41/RXD32
P42/TXD32
P43/IRQ0
AVCC
PBO/AN0
PB1/AN1
PB2/AN2
PB3/AN3
PB4/AN4
PB5/AN5
PB6/AN6
PB7/AN7
PC0/AN8
PC1/AN9
PC2/AN10
PC3/AN11
AVSS
P90/SEG33
P87/SEG32
P86/SEG31
P85/SEG30
P84/SEG29
P83/SEG28
P82/SEG27
P81/SEG26
P80/SEG25
P79/SEG24
P76/SEG23
P75/SEG22
P74/SEG21
P73/SEG20
P72/SEG19
P71/SEG18
P70/SEG17
P67/SEG16
P66/SEG15
P65/SEG14
P64/SEG13
P63/SEG12
P32/SEG11
P61/SEG10
P60/SEG9
SEG18
SEG19
SEG20
SEG21
SEG22
SEG23
5VS
MICM
WET
CPU5V
NOISV
BATTV
TDETV
TEMPV
RSSIV
PTT
SEG17
SEG16
SEG15
SEG14
SEG13
SEG12
SEG11
SEG10
SEG9
SEG8
SEG7
SEG6
SEG5
SEG4
SEG3
SEG2
SEG1
DW
SCAN
CHWX
16CH
DPWN
UP
SQL
HL
ATIS8
ATIS7
ATIS6
ATIS5
ATIS4
ATIS3
ATIS2
ATIS1
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
DS360
A0153A
COM1
COM2
COM3
SEG1
SEG2
SEG3
SEG4
SEG5
SEG6
SEG7
SEG8
SEG9
SEG10
SEG11
SEG12
SEG13
SEG14
SEG15
SEG16
SEG17
SEG18
SEG19
SEG20
SEG21
SEG22
SEG23
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
SEG1
SEG2
SEG3
SEG4
SEG5
SEG6
SEG7
SEG8
SEG9
SEG10
SEG11
SEG12
SEG13
SEG14
SEG15
SEG16
SEG17
SEG18
SEG19
SEG20
SEG21
SEG22
SEG23
COM1
COM2
COM3
T5VS
V5VS
LEDL
ESCK
ESDA
LEDK
CP361
UNLK
BPFS
C370
18 P
C371
22 P
C372
0.1
C373
0.1
C374
0.1
C375
0.1
P57/WKP7/SEG8
P56/WKP6/SEG7
P55/WKP5/SEG6
P54/WKP4/SEG5
P53/WKP3/SEG4
P52/WKP2/SEG3
P51/WKP1/SEG2
P50/WKP0/SEG1
PA0/COM1
PA1/COM2
PA2/COM3
PA3/COM4
VCC
V0
V1
V2
V3
VSS
CVCC
P37/AEVL
P36/AEVH
P35/TXD31
P34/RXD31
P33/SCK31
P32/RESO
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
P10/TMOW
P11/TMOFL
P12/TMOFH
P13/IMIG
P14/IRQ4/ADTRG
P15/IRQ1/TMIC
P16/IRQ2
P17/IRQ3/TMIF
X1
X2
VSS
OCS2
OSC1
TEST
RES
P20/SCK1
P21/SI1
P22/SD1
P23
P24
P25
P26
P27
P30/PWM
P31/UD
R212
1.5 k
R213
68 k
AFV
VOLO
AFV
MOD
BEPST
VOLIN
BEPST
BEPST
VOLIN
VOLIN
NOISV
MOD
BEPST
RSSIV
VOLIN
BEPO
DET
BEEP
NOISV
RSSIV
VOLO
AFV
MOD
BEPST
VOLIN
BEPO
BEPO
DET
BEEP
NOISV
RSSIV
VOLO
AFV
MOD
BEPST
VOLIN
BEPO
DET
MOD
BEPO
5V
1.9 V
7.9872 MHz
3.4 Vp-p
SECTION 11
VOLTAGE DIAGRAM
11 - 1
11-1 MAIN UNIT