ESCC Qualified SMPS Capacitors
High Voltage Chip/Leaded Capacitors
HIGH VOLTAGE CHIP CAPACITORS
Capacitors, Fixed, Chip, Ceramic Dielectric, Type II, High
Voltage, Based on Styles 1812 and 1825 for use in ESCC
space programs, according to ESCC Generic Specification
3009 and associated Detail Specification 3009/034 as
recommended by the Space Components Coordination
Group. (ranges in table below)
Note: Variants 01 to 12: metallized pads
Size
1812
Variant
01
02
03
04
05
06
07
08
09
10
11
12
1825
Rated
Voltage Tolerance Capacitance
(kV)
(%)
Code (E12)
±10
1.0
392 - 223
±20
±10
2.0
152 - 182
±20
±10
3.0
821 - 102
±20
±10
1.0
273 - 563
±20
±10
2.0
222 - 682
±20
±10
3.0
821 - 392
±20
HOW TO ORDER
Parts should be ordered using the ESCC variant number as follows:
3009034 XX
B
XXX
Capacitance
Code
The first two digits represent
significant figures and the third
digit specifies the number of
zeros to follow; i.e.
102 = 1000pF
103 = 10000pF
Test Level
Detail Spec Type
Variant
C = Standard test level
Number
(per table) B = Level C plus serialized
and capacitance
recorded before and
after 100% burn-in.
Eg 300903401C223
HIGH VOLTAGE LEADED CAPACITORS
Capacitors, Fixed, Ceramic Dielectric, Type II, High Voltage,
1.0 to 5.0 kV, Based on Case Styles VR, CV and CH for use
in ESCC space programs, according to ESCC Generic
Specification 3001 and associated Detail Specification
3001/034 as recommended by the Space Components
Coordination Group. (ranges in table)
Note 1: Lead Types
a - Leaded Radial (epoxy coated)
b - Leaded Radial (Polyurethane Varnish)
c - Straight Dual in Line
d - L Dual in Line
Note 2: Tolerances of ±10% and ±20% are available
Case
Lead
Size Variant Type 1.0kV
VR30S
VR30
VR40
VR50
VR66
VR84
VR90
CV41
CH41
CH41
CV51
CH51
CH51
CV61
CH61
CH61
CV76
CH76
CH76
CV91
CH91
CH91
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
a
a
a
a
a
a
a
b
c
d
b
c
d
b
c
d
b
c
d
b
c
d
392
273
473
154
224
684
125
473
473
473
154
154
154
224
224
224
684
684
684
125
125
125
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
203
563
124
274
564
105
275
124
124
124
274
274
274
564
564
564
105
105
105
275
275
275
Capacitance Code (E12)
2.0kV
3.0kV
4.0kV
152
222
822
183
393
473
184
822
822
822
183
183
183
393
393
393
473
473
473
184
184
184
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
182
682
153
333
823
154
334
153
153
153
333
333
333
823
823
823
154
154
154
334
334
334
821
821
472
123
223
473
823
472
472
472
123
123
123
223
223
223
473
473
473
823
823
823
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
102
392
103
183
393
683
184
103
103
103
183
183
183
393
393
393
683
683
683
184
184
184
5.0kV
HOW TO ORDER
Parts should be ordered using the ESCC variant
number as follows:
182
562
103
183
473
182
182
182
562
562
562
103
103
103
183
183
183
473
473
473
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
222
822
153
393
124
222
222
222
822
822
822
153
153
153
393
393
393
124
124
124
332
682
123
223
-
-
-
-
392
103
183
563
332
332
332
682
682
682
123
123
123
223
223
223
-
-
-
-
-
-
-
-
-
-
-
-
392
392
392
103
103
103
183
183
183
563
563
563
3001034
Detail Spec
Number
XX
Type Variant
(per table above)
B
Test Level
C = Standard test level
B = Level C plus serialized
and capacitance recorded
before and after 100%
burn-in.
XXX
Capacitance
Code
The first two digits represent
significant figures and the third
digit specifies the number of
zeros to follow; i.e.
102 = 1000pF
103 = 10000pF
K
Capacitance
Tolerance
K = 10%
M = 20%
X
Voltage
M = 1kV
P = 2kV
R = 3kV
S = 4kV
Z = 5kV
Eg 300103412C274KM
56
ESCC Qualified SMPS Capacitors
High Capacitance
HIGH CAPACITANCE LEADED CAPACITORS
Capacitors, Fixed, Ceramic Dielectric, Type II, High
Capacitance, Based on Case Styles BR, CV and CH for use
in ESCC space programs, according to ESCC Generic
Specification 3001 and associated Detail Specification
3001/030 as recommended by the Space Components
Coordination Group. (see ranges in table below)
Case
Size Variant Figure
BR40
BR50
BR66
BR72
BR84
CV41
CH41
CH41
CH42
CH42
CH43
CH43
CH44
CH44
CV51
CH51
CH51
CH52
CH52
CH53
CH53
CH54
CH54
CV61
CH61
CH61
CH62
CH62
CH63
CH63
CH64
CH64
CV71
CH71
CH71
CH72
CH72
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
˜31
32
33
34
35
36
37
a
a
a
a
a
b
c
d
c
d
c
d
c
d
b
c
d
c
d
c
d
c
d
b
c
d
c
d
c
d
c
d
b
c
d
c
d
Note 1: Lead Types
a - Leaded Radial (epoxy coated)
b - Leaded Radial (Polyurethane Varnish)
c - Straight Dual in Line
d - L Dual in Line
Note 2: Tolerances of ±10% and ±20% are available
Capacitance Code (E12)
50V
185 - 335
395 - 565
685 - 106
126 - 186
126 - 186
185 - 335
185 - 335
185 - 335
395 - 685
395 - 685
825 - 106
825 - 106
126
126
395 - 565
395 - 565
395 - 565
685 - 106
685 - 106
126 - 156
126 - 156
186 - 226
186 - 226
685 - 106
685 - 106
685 - 106
126 - 226
126 - 226
276 - 336
276 - 336
396
396
126 - 186
126 - 186
126 - 186
226 - 396
226 - 396
100V
125 - 275
225 - 395
475 - 825
825 - 156
825 - 156
125 - 275
125 - 275
125 - 275
335 - 565
335 - 565
685 - 825
685 - 825
106
106
225 - 395
225 - 395
225 - 395
475 - 825
475 - 825
106 - 126
106 - 126
156
156
475 - 825
475 - 825
475 - 825
106 - 156
106 - 156
186 - 226
186 - 226
276 - 336
276 - 336
825 - 156
825 - 156
825 - 156
186 - 276
186 - 276
200V
334 - 564
684 - 105
105 - 225
225 - 335
225 - 335
334 - 564
334 - 564
334 - 564
684 - 125
684 - 125
155 - 185
155 - 185
225
225
684 - 105
684 - 105
684 - 105
125 - 225
125 - 225
275 - 335
275 - 335
395
395
105 - 225
105 - 225
105 - 225
275 - 475
275 - 475
565 - 685
565 - 685
825 - 106
825 - 106
225 - 335
225 - 335
225 - 335
395 - 685
395 - 685
500V
124 - 224
274 - 394
474 - 105
824 - 155
824 - 155
124 - 224
124 - 224
124 - 224
274 - 474
274 - 474
564 - 684
564 - 684
824 - 105
824 - 105
274 - 394
274 - 394
274 - 394
474 - 824
474 - 824
105 - 125
105 - 125
155
155
474 - 105
474 - 105
474 - 105
105 - 185
105 - 185
225 - 275
225 - 275
335
335
824 - 155
824 - 155
824 - 155
185 - 335
185 - 335
Case
Size Variant Figure
CH73
CH73
CH74
CH74
CV76
CH76
CH76
CH77
CH77
CH78
CH78
CH79
CH79
CH81
CH81
CH82
CH82
CH83
CH83
CH84
CH84
CH86
CH86
CH87
CH87
CH88
CH88
CH89
CH89
CH91
CH91
CH92
CH92
CH93
CH93
CH94
CH94
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
c
d
c
d
b
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
c
d
Capacitance Code (E12)
50V
476 - 566
476 - 566
686
686
126 - 186
126 - 186
126 - 186
226 - 396
226 - 396
476 - 566
476 - 566
686
686
156 - 226
156 - 226
276 - 476
276 - 476
566 - 686
566 - 686
826
826
226 - 336
226 - 336
396 - 686
396 - 686
826 - 107
826 - 107
127
127
396 - 476
396 - 476
566 - 107
566 - 107
127 - 157
127 - 157
187
187
100V
336 - 396
336 - 396
476
476
825 - 156
825 - 156
825 - 156
186 - 276
186 - 276
336 - 396
336 - 396
476
476
126 - 186
126 - 186
226 - 396
226 - 396
476 - 566
476 - 566
686
686
156 - 276
156 - 276
336 - 566
336 - 566
686 - 826
686 - 826
107
107
336 - 396
336 - 396
476 - 826
476 - 826
107 - 127
107 - 127
157
157
200V
825 - 106
825 - 106
126
126
225 - 335
225 - 335
225 - 335
395 - 685
395 - 685
825 - 106
825 - 106
126
126
225 - 395
225 - 395
475 - 825
475 - 825
106 - 126
106 - 126
156
156
395 - 685
395 - 685
825 - 156
825 - 156
186 - 226
186 - 226
276
276
825 - 106
825 - 106
126 - 226
126 - 226
276 - 336
276 - 336
396
396
500V
395 - 475
395 - 475
565
565
824 - 155
824 - 155
824 - 155
185 - 335
185 - 335
395 - 475
395 - 475
565
565
824 - 155
824 - 155
155 - 225
155 - 225
HOW TO ORDER
Parts should be ordered using the ESCC variant number as follows:
3001030
Detail Spec
Number
XX
Type Variant
(per table above)
B
Test Level
C = Standard test level
B = Level C plus serialized and
capacitance recorded before
and after 100% burn-in.
XXX
Capacitance
Code
The first two digits represent
significant figures and the third
digit specifies the number of
zeros to follow; i.e.
102 = 1000pF
103 = 10000pF
K
Capacitance
Tolerance
K = 10%
M = 20%
X
Voltage
C = 50V
E = 100V
G = 200V
L = 500V
EG 300103018C106KC
Lot Acceptance Testing is available for all our ESCC qualified ranges.
LAT 1
LAT 2
LAT 3
42 samples
→
12 mechanical + 20 life test + 6 for TC + 4 for solder
30 samples
→
20 life test + 6 for TC + 4 for solder
10 samples
→
6 for TC + 4 for solder
57
SMPS Capacitors
ESCC DETAIL SPECIFICATION NO. 3009/034
PHYSICAL DIMENSIONS
Millimeters (Inches)
L
I
L
l
Symbol
Variants 01 to 06
Min.
4.20
(0.165)
2.80
(0.110)
–
0.25
(0.010)
Variants 07 to 12
Min.
4.20
(0.165)
5.67
(0.223)
–
0.25
(0.010)
Max.
5.00
(0.197)
3.60
(0.142)
3.00
(0.118)
0.75
(0.030)
Max.
5.00
(0.197)
6.67
(0.263)
3.30
(0.130)
0.75
(0.030)
e
e
M
=
=
M
M
ESCC DETAIL SPECIFICATION NO. 3001/034
PHYSICAL DIMENSIONS – VR STYLE
Millimeters (Inches)
B
F
Variant
01
Case
Size
VR30S
VR30
VR40
VR50
VR66
VR84
VR90
B
Max.
7.62
(0.300)
7.62
(0.300)
10.16
(0.400)
12.7
(0.500)
17.5
(0.689)
23.62
(0.930)
23.5
(0.925)
Ød
Min.
Max.
0.46
(0.018)
0.46
(0.018)
0.46
(0.018)
0.59
(0.023)
0.86
(0.034)
0.86
(0.034)
0.86
(0.034)
0.56
(0.022)
0.56
(0.022)
0.56
(0.022)
0.69
(0.027)
0.96
(0.038)
0.96
(0.038)
0.96
(0.038)
E
Min.
4.58
(0.180)
4.58
(0.180)
4.58
(0.180)
9.66
(0.380)
14.2
(0.559)
20.4
(0.803)
20.4
(0.803)
Max.
5.58
(0.220)
5.58
(0.220)
5.58
(0.220)
10.66
(0.420)
15.2
(0.598)
22.0
(0.866)
22.0
(0.866)
F
Max.
5.00
(0.197)
5.00
(0.197)
5.00
(0.197)
5.10
(0.201)
6.40
(0.252)
6.40
(0.252)
6.40
(0.252)
H
Max.
4.60
(0.181)
9.62
(0.379)
11.7
(0.461)
14.2
(0.559)
16.5
(0.650)
19.78
(0.779)
42.0
(1.654)
J
Max.
1.50
(0.059)
1.50
(0.059)
1.50
(0.059)
1.50
(0.059)
1.50
(0.059)
1.50
(0.059)
1.50
(0.059)
L
Min.
31.7
(1.248)
31.7
(1.248)
31.7
(1.248)
31.7
(1.248)
31.7
(1.248)
31.7
(1.248)
31.7
(1.248)
H
J
02
03
L
04
05
06
E
Ød
07
ESCC DETAIL SPECIFICATION NO. 3001/034
PHYSICAL DIMENSIONS – CV STYLE
Millimeters (Inches)
F
Variant
08
Case
Size
CV41
CV51
CV61
CV76
CV91
B
Max.
10.6
(0.417)
11.9
(0.469)
16.5
(0.650)
22.7
(0.894)
22.7
(0.894)
Ød
Min.
Max.
0.65
(0.026)
0.85
(0.033)
0.85
(0.033)
0.85
(0.033)
1.15
(0.045)
0.75
(0.030)
0.95
(0.037)
0.95
(0.037)
0.95
(0.037)
1.25
(0.049)
E
Min.
7.70
(0.303)
9.66
(0.380)
14.74
(0.580)
20.4
(0.803)
20.4
(0.803)
Max.
8.70
(0.343)
10.66
(0.420)
15.74
(0.620)
22.0
(0.866)
22.0
(0.866)
F
Max.
3.80
(0.150)
3.80
(0.150)
3.80
(0.150)
3.80
(0.150)
3.80
(0.150)
H
Max.
8.70
(0.343)
10.7
(0.421)
13.6
(0.535)
16.6
(0.654)
40.6
(1.598)
L
Min.
22.0
(0.866)
22.0
(0.866)
22.0
(0.866)
22.0
(0.866)
22.0
(0.866)
Max.
28.0
(1.102)
28.0
(1.102)
28.0
(1.102)
28.0
(1.102)
28.0
(1.102)
B
H
Ød
11
14
17
20
L
L
E
58
SMPS Capacitors
ESCC DETAIL SPECIFICATION NO. 3001/034
PHYSICAL DIMENSIONS – CH STYLE, D.I.L.
a1
A
L
b
D
e
b1
E
Variant
07
09
11
13
16
18
20
22
25
27
29
31
34
36
38
40
43
45
47
49
51
53
55
57
59
61
63
65
67
69
71
73
Case
Size
CH41
CH42
CH43
CH44
CH51
CH52
CH53
CH54
CH61
CH62
CH63
CH64
CH71
CH72
CH73
CH74
CH76
CH77
CH78
CH79
CH81
CH82
CH83
CH84
CH86
CH87
CH88
CH89
CH91
CH92
CH93
CH94
Millimeters (Inches)
A
Max.
3.80
7.40
11.1
14.8
3.80
7.40
11.1
14.8
3.80
7.40
11.1
14.8
3.80
7.40
11.1
14.8
3.80
7.40
11.1
14.8
3.80
7.40
11.1
14.8
3.80
7.40
11.1
14.8
3.80
7.40
11.1
14.8
(0.150)
(0.291)
(0.437)
(0.583)
(0.150)
(0.291)
(0.437)
(0.583)
(0.150)
(0.291)
(0.437)
(0.583)
(0.150)
(0.291)
(0.437)
(0.583)
(0.150)
(0.291)
(0.437)
(0.583)
(0.150)
(0.291)
(0.437)
(0.583)
(0.150)
(0.291)
(0.437)
(0.583)
(0.150)
(0.291)
(0.437)
(0.583)
D
Max.
8.70
8.70
8.70
8.70
10.7
10.7
10.7
10.7
13.6
13.6
13.6
13.6
21.6
21.6
21.6
21.6
16.6
16.6
16.6
16.6
38.2
38.2
38.2
38.2
38.2
38.2
38.2
38.2
40.6
40.6
40.6
40.6
(0.343)
(0.343)
(0.343)
(0.343)
(0.421)
(0.421)
(0.421)
(0.421)
(0.535)
(0.535)
(0.535)
(0.535)
(0.850)
(0.850)
(0.850)
(0.850)
(0.654)
(0.654)
(0.654)
(0.654)
(1.504)
(1.504)
(1.504)
(1.504)
(1.504)
(1.504)
(1.504)
(1.504)
(1.598)
(1.598)
(1.598)
(1.598)
E
Min.
7.70
7.70
7.70
7.70
9.66
9.66
9.66
9.66
13.5
13.5
13.5
13.5
14.74
14.74
14.74
14.74
19.52
19.52
19.52
19.52
9.66
9.66
9.66
9.66
14.74
14.74
14.74
14.74
19.52
19.52
19.52
19.52
(0.303)
(0.303)
(0.303)
(0.303)
(0.380)
(0.380)
(0.380)
(0.380)
(0.531)
(0.531)
(0.531)
(0.531)
(0.580)
(0.580)
(0.580)
(0.580)
(0.769)
(0.769)
(0.769)
(0.769)
(0.380)
(0.380)
(0.380)
(0.380)
(0.580)
(0.580)
(0.580)
(0.580)
(0.769)
(0.769)
(0.769)
(0.769)
Max.
8.70
8.70
8.70
8.70
10.66
10.66
10.66
10.66
14.5
14.5
14.5
14.5
15.74
15.74
15.74
15.74
21.12
21.12
21.12
21.12
10.66
10.66
10.66
10.66
15.74
15.74
15.74
15.74
21.12
21.12
21.12
21.12
(0.343)
(0.343)
(0.343)
(0.343)
(0.420)
(0.420)
(0.420)
(0.420)
(0.571)
(0.571)
(0.571)
(0.571)
(0.620)
(0.620)
(0.620)
(0.620)
(0.831)
(0.831)
(0.831)
(0.831)
(0.420)
(0.420)
(0.420)
(0.420)
(0.620)
(0.620)
(0.620)
(0.620)
(0.831)
(0.831)
(0.831)
(0.831)
F
Max.
9.20
9.20
9.20
9.20
10.7
10.7
10.7
10.7
14.9
14.9
14.9
14.9
16.8
16.8
16.8
16.8
21.6
21.6
21.6
21.6
12.0
12.0
12.0
12.0
18.9
18.9
18.9
18.9
24.0
24.0
24.0
24.0
(0.362)
(0.362)
(0.362)
(0.362)
(0.421)
(0.421)
(0.421)
(0.421)
(0.587)
(0.587)
(0.587)
(0.587)
(0.661)
(0.661)
(0.661)
(0.661)
(0.850)
(0.850)
(0.850)
(0.850)
(0.472)
(0.472)
(0.472)
(0.472)
(0.744)
(0.744)
(0.744)
(0.744)
(0.945)
(0.945)
(0.945)
(0.945)
F
Symbol
a1
b
b1
e
L
Min.
-
0.45
(0.018)
0.204
(0.008)
2.49
(0.098)
12.0
(0.472)
Max.
2.00
(0.079)
0.55
(0.022)
0.304
(0.012)
2.59
(0.102)
14.0
(0.551)
Notes
1
1
1
2
1
Notes: 1 – All leads
2 – Each space
ESCC DETAIL SPECIFICATION NO. 3001/034
PHYSICAL DIMENSIONS – CH STYLE, L
A
L
b
D
e
L
E
L
Variant
10
13
16
19
22
Symbol
b
e
Millimeters (Inches)
Case
Size
CH41
CH51
CH61
CH76
CH91
A
Max.
3.80
3.80
3.80
3.80
3.80
(0.150)
(0.150)
(0.150)
(0.150)
(0.150)
D
Max.
8.70
10.7
13.6
16.6
40.6
(0.343)
(0.421)
(0.535)
(0.654)
(1.598)
E
Min.
7.70
9.66
13.5
19.52
19.52
Max.
F
Max.
(0.303) 8.70 (0.343) 9.20 (0.362)
(0.380) 10.66 (0.420) 10.7 (0.421)
(0.531) 14.5 (0.571) 14.9 (0.587)
(0.769) 21.12 (0.831) 21.6 (0.850)
(0.769) 21.12 (0.831) 24.0 (0.945)
Min.
0.45
(0.018)
2.49
(0.098)
2.04
(0.080)
Max.
0.55
(0.022)
2.59
(0.102)
3.01
(0.120)
Notes
1
2
1
F
L
Notes: 1 – All leads
2 – Each space
59
SMPS Capacitors
ESCC DETAIL SPECIFICATION NO. 3001/030
PHYSICAL DIMENSIONS – BR STYLE
Millimeters (Inches)
B
H
J
F
Variant
01
02
03
Case
Size
BR40
BR50
BR66
BR72
BR84
B
Max.
10.16
(0.400)
12.7
(0.500)
17.5
(0.689)
19.3
(0.760)
23.62
(0.930)
Ød
Min.
Max.
0.46
(0.018)
0.59
(0.023)
0.86
(0.034)
0.86
(0.034)
0.71
(0.028)
0.56
(0.022)
0.69
(0.027)
0.96
(0.038)
0.96
(0.038)
0.81
(0.032)
E
Min.
4.58
(0.180)
9.66
(0.380)
14.2
(0.559)
14.74
(0.580)
18.93
(0.745)
Max.
5.58
(0.220)
10.66
(0.420)
15.2
(0.598)
15.74
(0.620)
20.83
(0.820)
F
Max.
5.00
(0.197)
5.10
(0.201)
6.40
(0.252)
6.40
(0.252)
6.40
(0.252)
H
Max.
11.7
(0.461)
14.2
(0.559)
16.5
(0.650)
24.0
(0.945)
19.78
(0.779)
J
Max.
1.50
(0.059)
1.50
(0.059)
1.50
(0.059)
1.50
(0.059)
1.50
(0.059)
L
Min.
31.7
(1.248)
31.7
(1.248)
31.7
(1.248)
31.7
(1.248)
31.7
(1.248)
L
04
05
E
Ød
ESCC DETAIL SPECIFICATION NO. 3001/030
PHYSICAL DIMENSIONS – CV STYLE
Millimeters (Inches)
F
Variant
06
Case
Size
CV41
CV51
CV61
CV71
CV76
B
Max.
10.6
(0.417)
11.9
(0.469)
16.5
(0.650)
17.8
(0.701)
22.7
(0.894)
Ød
Min.
Max.
0.65
(0.026)
0.85
(0.033)
0.85
(0.033)
0.85
(0.033)
0.85
(0.033)
0.75
(0.030)
0.95
(0.037)
0.95
(0.037)
0.95
(0.037)
0.95
(0.037)
E
Min.
7.70
(0.303)
9.66
(0.380)
14.74
(0.580)
14.74
(0.580)
20.4
(0.803)
Max.
8.70
(0.343)
10.66
(0.420)
15.74
(0.620)
15.74
(0.620)
22.0
(0.866)
F
Max.
3.80
(0.150)
3.80
(0.150)
3.80
(0.150)
3.80
(0.150)
3.80
(0.150)
H
Max.
8.70
(0.343)
10.7
(0.421)
13.6
(0.535)
21.6
(0.850)
16.6
(0.654)
L
Min.
22.0
(0.866)
22.0
(0.866)
22.0
(0.866)
22.0
(0.866)
22.0
(0.866)
Max.
28.0
(1.102)
28.0
(1.102)
28.0
(1.102)
28.0
(1.102)
28.0
(1.102)
B
H
Ød
15
24
33
42
L
L
E
60
单片机
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
