RF W
IREWOUND
C
HIP
I
NDUCTORS
These high frequency High-Q chip inductors feature a
monolithic body made of low loss ceramic wound with wire to
achieve optimal high frequency performance.
These RF chip inductors are compact in size and are provided on
tape and reel packaging which makes them ideal for high volume RF
applications. They feature a nickel barrier with a top plating of gold
for the ceramic core types (all 0402, all 0603, and most 0805 types),
and with a top plating of 100% tin for the ferrite core types (0805
size, 470 nH and higher). Most inductance values between those
listed are available on request.
a
ppliCaTionS
• CELL/PCS Modules
• Broadband Components
• RF Tranceivers
• Cable Modem
• Bluetooth
• Wireless LAN
• RFID
• Cordless Phone
• Computer Peripherals
• ASDL
p
RoDuCT
R
ange
S
ummaRy
EIA SIZE (mm)
0402 (1005)
0603 (1608)
0805 (2012)
SIZE CODE
L-07
L-14
L-15
L RANGE
1.0 - 120 nH
2.0 - 470 nH
2.2 - 10,000 nH
Q FACTOR (Typ.)
55 (900 MHz)
60 (900 MHz)
60 (500 MHz)
SRF (Typ.)
>11 GHz (1.0 nH)
>13 GHz (2.0 nH)
>11 GHz (2.2 nH)
TEMPERATURE
-40°C to + 125°C
-40°C to + 125°C
-40°C to + 125°C*
*-40 deg. C to +85 deg. C for ferrite core types
M
ECHANICAL
C
HARACTERISTICS
W
S
T
0402 (1005)
Inches
mm
0603 (1608)
Inches
mm
0805 (2012)
Inches
mm
L
Length
Width
Thickness
End Band
.039 ±.004” (1.00 ±.10)
.022 ±.004” (0.55 ±.10)
.020 ±.004” (0.50 ±.10)
.008 ±.004” (0.20 ±.10)
.063 ±.008”
.041 ±.008”
.041 ±.008”
.014 ±.004”
(1.60 ±.20)
(1.05 ±.20)
(1.05 ±.20)
(0.35 ±.10)
.079 ±.008”
.049 ±.008”
.047 ±.008”
.016 ±.004”
(2.00 ±.20)
(1.25 ±.20)
(1.20 ±.20)
(0.40 ±.10)
H
OW TO
O
RDER
L-
DEVICE
Inductor
07
SIZE
07 = 0402
14 = 0603
15 = 0805
W
TYPE
W = Wirewound on
Ceramic Core
F = Wirewound on
Ferrite Core
4N3
VALUE
See Table
C
S
G
J
K
=
=
=
=
=
S
TOLERANCE*
± 0.2 nH
± 0.3 nH
± 2%
± 5%
± 10%
V
TERMINATION
V =
Ni / Au for “W”types,
4
MARKING
4 = No Marking
Tape and Reel
T
PACKAGING
Size Code Tape
Reel
Qty
0402
T
Paper
7” 10,000
0603
E Embossed 7”
3,000
0805
E Embossed 7”
2,000
Bulk (Loose Pcs.)
Size
All
Code
S
and V = Ni / 100% Sn for
“F” types
Example Part Number:
L-07W4N3SV4T
is: 0402 Wirewound, 4.3 nanohenry, +/- 0.3 nH tolerance, Ni / Au termination,
No Marking, Paper tape on a 7” reel.
www.johansontechnology.com
22
RF w
iRewounD
C
Hip
i
nDuCToR
S
eleCTion
C
HaRT
EIA Size
Inductor
Value
0402
(L-07)
C, S
C, S
C, S
C, S
C, S
C, S
C, S
C, S
C, S
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
1360 mA
1300 mA
1040 mA
1040 mA
1040 mA
960 mA
790 mA
640 mA
640 mA
840 mA
840 mA
840 mA
700 mA
640 mA
800 mA
760 mA
760 mA
680 mA
680 mA
680 mA
480 mA
680 mA
680 mA
480 mA
640 mA
640 mA
560 mA
560 mA
560 mA
420 mA
480 mA
420 mA
400 mA
400 mA
400 mA
400 mA
400 mA
400 mA
320 mA
320 mA
320 mA
100 mA
100 mA
100 mA
100 mA
100 mA
0603
(L-14)
0805
(L-15)
Core
Type
EIA Size
Inductor
Value
0402
(L-07)
0603
(L-14)
J, K
J, K
J, K
0805
(L-15)
Core
Type
Inductance
nH Code
1.0
1N0
1.2
1N2
1.6
1N6
1.8
1N8
1.9
1N9
2.0
2N0
2.2
2N2
2.4
2N4
2.6
2N6
2.7
2N7
3.3
3N3
3.6
3N6
3.9
3N9
4.3
4N3
4.7
4N7
5.1
5N1
5.6
5N6
6.2
6N2
6.8
6N8
7.5
7N5
8.2
8N2
8.7
8N7
9.0
9N0
9.5
9N5
10
10N
11
11N
12
12N
13
13N
15
15N
16
16N
18
18N
19
19N
20
20N
22
22N
23
23N
24
24N
27
27N
30
30N
33
33N
36
36N
39
39N
40
40N
43
43N
47
47N
51
51N
56
56N
68
68N
72
72N
82
82N
100
R10
110
R11
120
R12
150
R15
180
R18
220
R22
270
R27
Toler- Rated Toler- Rated Toler- Rated
ance Current ance Current ance Current
C, S
C, S
C, S
700 mA
700 mA
700 mA
C, S
C, S
700 mA C, S
700 mA
700 mA C, S
700 mA
700 mA C, S
700 mA
700 mA C, J, K
700 mA
700 mA
700 mA
700 mA
C, G J, K
800 mA
800 mA
800 mA
600 mA
600 mA
600 mA
600 mA
600 mA
600 mA
C, S
C, S
C, S
C, S
C, S
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
C, J, K
G, J, K
G, J, K
G, J, K
Inductance
nH Code
330
R33
390
R39
470
R47
560
R56
680
R68
820
R82
1000 1R0
1200 1R2
1500 1R5
1800 1R8
2200 2R2
2700 2R7
3300 3R3
3900 3R9
4700 4R7
5600 5R6
6800 6R8
8200 8R2
10000 10R
Toler- Rated Toler- Rated Toler- Rated
ance Current ance Current ance Current
150 mA G, J, K
100 mA G, J, K
100 mA J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
J, K
300 mA
Ceramic
210 mA
500 mA
450 mA
400 mA
300 mA
180 mA
150 mA
130 mA
120 mA
110 mA
100 mA
210 mA
200 mA
180 mA
160 mA
130 mA
120 mA
80 mA
J, K
C, G, J, K
Consult factory for Non-Standard values.
700 mA
700 mA G, J, K
700 mA
700 mA G, J, K
J, K
G, J, K 700 mA G, J, K
G, J, K 700 mA G, J, K
G, J, K 700 mA G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
700 mA
700 mA
700 mA
700 mA
600 mA
700 mA
600 mA
600 mA
600 mA
600 mA
600 mA
600 mA
600 mA
G, J, K 600 mA
G, J, K 600 mA
J, K 600 mA
G, J, K 600 mA
G, J, K 500 mA
J, K 600 mA
G, J, K 600 mA G, J, K 500 mA
700 mA
600 mA
600 mA
600 mA
600 mA
400 mA
400 mA
400 mA
300 mA
280 mA
240 mA
200 mA
170 mA
J, K
G, J, K
J, K
G, J, K
G, J, K
600 mA
500 mA
600 mA
500 mA
500 mA
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
100 mA G, J, K
100 mA G, J, K
100 mA
100 mA G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K 500 mA
G, J, K 500 mA
G, J, K
G, J, K
G, J, K
G, J, K
G, J, K
500 mA
400 mA
400 mA
400 mA
350 mA
See web page for WireWound Inductor Product Detail
Summary by part number
23
www.johansontechnology.com
CERAMIC CORE (“VV” Type)
FERRITE CORE (“F” Type)
RF C
HaRaCTeRiSTiCS
C
HaRaCTeRiSTiCS
(T
ypiCal
)
Q vs Frequency for 0402 Size
2.2 nH
5.6 nH
15 nH
3.3 nH
8.2 nH
36 nH
Inductance (nH)
180
160
140
120
Q
100
80
60
40
20
0
100
60
50
40
30
20
10
0
100
L vs Frequency for 0402 Size
2.2 nH
5.6 nH
15 nH
3.3 nH
8.2 nH
36 nH
1000
Frequency (MHz)
10000
1000
Frequency (MHz)
10000
120
100
80
60
40
20
0
100
Q
Q vs Frequency for 0603 Size
2.0 nH
22 nH
180 nH
10 nH
100 nH
400
350
300
Inductance (nH)
250
200
150
100
50
0
L vs Frequency for 0603 Size
2.0nH
10 nH
22 nH
100 nH
180 nH
1000
Frequency (MHz)
10000
100
1000
Frequency (MHz)
10000
90
80
70
60
Q
50
40
30
20
10
0
100
Q vs Frequency for 0805 Size
2.7nH
100nH
470nH
27.0nH
270nH
Inductance (nH)
1400
1200
1000
800
600
400
200
L vs Frequency for 0805 Size
2.7nH
100nH
470nH
27.0nH
270nH
680nH
680nH
1000
Frequency (MHz)
10000
0
100
1000
Frequency (MHz)
10000
www.johansontechnology.com
24
0402 I
NDUCTANCE
R
ANGE
/ E
LECTRICAL
C
HARACTERISTICS
Part Number
(Standard Tol.)
Inductance
@ 250MHz
Availiable Tolerances
@ 250MHz
Q (min.)
@ 250MHz
Q (Typ.)
@ 900MHz
Q (Typ.)
@ 1.8GHz
SRF
(min.)
DC Resistance Rated Current
(max.)
(max.)
L-07W1N0SV4T
L-07W1N2SV4T
L-07W1N8SV4T
L-07W1N9SV4T
L-07W2N0SV4T
L-07W2N2SV4T
L-07W2N4SV4T
L-07W2N7SV4T
L-07W3N3JV4T
L-07W3N6JV4T
L-07W3N9JV4T
L-07W4N3JV4T
L-07W4N7JV4T
L-07W5N1JV4T
L-07W5N6JV4T
L-07W6N2JV4T
L-07W6N8JV4T
L-07W7N5JV4T
L-07W8N2JV4T
L-07W8N7JV4T
L-07W9N0JV4T
L-07W9N5JV4T
L-07W10NJV4T
L-07W11NJV4T
L-07W12NJV4T
L-07W13NJV4T
L-07W15NJV4T
L-07W16NJV4T
L-07W18NJV4T
L-07W19NJV4T
L-07W20NJV4T
L-07W22NJV4T
L-07W23NJV4T
L-07W24NJV4T
L-07W27NJV4T
L-07W30NJV4T
L-07W33NJV4T
L-07W36NJV4T
L-07W39NJV4T
L-07W40NJV4T
L-07W43NJV4T
L-07W47NJV4T
L-07W51NJV4T
L-07W56NJV4T
L-07W68NJV4T
1.0 nH
1.2 nH
1.8 nH
1.9 nH
2.0 nH
2.2 nH
2.4 nH
2.7 nH
3.3 nH
3.6 nH
3.9 nH
4.3 nH
4.7 nH
5.1 nH
5.6 nH
6.2 nH
6.8 nH
7.5 nH
8.2 nH
8.7 nH
9.0 nH
9.5 nH
10.0 nH
11.0 nH
12.0 nH
13.0 nH
15.0 nH
16.0 nH
18.0 nH
19.0 nH
20.0 nH
22.0 nH
23.0 nH
24.0 nH
27.0 nH
30.0 nH
33.0 nH
36.0 nH
39.0 nH
40.0 nH
43.0 nH
47.0 nH
51.0 nH
56.0 nH
68.0 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
+/-5%, +/-10%
+/-5%, +/-10%
+/-5%, +/-10%
13
13
16
16
16
18
15
16
19
19
19
18
15
20
20
20
20
22
22
18
22
18
21
24
24
24
24
24
24
24
24
24
24
24
24
24
24
24
24
24
24
22@200MHz
22@200MHz
22@200MHz
22@200MHz
49
49
50
50
51
52
52
50
53
55
60
55
55
58
61
57
58
59
60
60
60
55
56
61
58
60
61
58
58
58
54
54
55
54
55
52
52
52
51
51
50
50
49
49
42
60
60
60
60
62
65
65
65
72
72
76
82
82
83
89
80
80
90
87
83
83
76
76
86
77
77
86
77
77
77
74
73
73
74
75
64
64
64
48
48
46
46
N/A
N/A
N/A
6.0 GHz
6.0 GHz
6.0 GHz
6.0 GHz
6.0 GHz
6.0 GHz
6.0 GHz
6.0 GHz
6.0 GHz
6.0 GHz
5.8 GHz
6.0 GHz
4.8 GHz
5.8 GHz
5.8 GHz
5.8 GHz
4.8 GHz
5.8 GHz
4.4 GHz
4.1 GHz
4.2 GHz
4.0 GHz
3.9 GHz
3.7 GHz
3.6 GHz
3.5 GHz
3.3 GHz
3.1 GHz
3.1 GHz
3.0 GHz
3.0 GHz
2.7 GHz
2.7 GHz
2.7 GHz
2.5 GHz
2.3 GHz
2.3 GHz
2.3 GHz
2.1 GHz
2.3 GHz
2.0 GHz
2.1 GHz
1.7 GHz
1.7 GHz
1.6 GHz
0.045
Ω
0.060
Ω
0.070
Ω
0.070
Ω
0.070
Ω
0.070
Ω
0.068
Ω
0.120
Ω
0.066
Ω
0.066
Ω
0.066
Ω
0.091
Ω
0.130
Ω
0.083
Ω
0.083
Ω
0.083
Ω
0.083
Ω
0.104
Ω
0.104
Ω
0.200
Ω
0.104
Ω
0.200
Ω
0.195
Ω
0.120
Ω
0.120
Ω
0.210
Ω
0.172
Ω
0.220
Ω
0.230
Ω
0.202
Ω
0.250
Ω
0.300
Ω
0.214
Ω
0.300
Ω
0.298
Ω
0.300
Ω
0.350
Ω
0.403
Ω
0.550
Ω
0.438
Ω
0.810
Ω
0.830
Ω
0.820
Ω
0.970
Ω
1.120
Ω
1360 mA
1300 mA
1040 mA
1040 mA
1040 mA
960 mA
790 mA
640 mA
840 mA
840 mA
840 mA
700 mA
640 mA
800 mA
760 mA
760 mA
680 mA
680 mA
680 mA
480 mA
680 mA
680 mA
480 mA
640 mA
640 mA
560 mA
560 mA
560 mA
420 mA
480 mA
420 mA
400 mA
400 mA
400 mA
400 mA
400 mA
400 mA
320 mA
320 mA
320 mA
100 mA
100 mA
100 mA
100 mA
100 mA
www.johansontechnology.com
25
0402 I
NDUCTANCE
R
ANGE
/ E
LECTRICAL
C
HARACTERISTICS
Part Number
(Standard Tol.)
Inductance
@ 250MHz
Availiable Tolerances
@ 250MHz
Q (min.)
@ 250MHz
Q (Typ.)
@ 900MHz
Q (Typ.)
@ 1.8GHz
SRF
(min.)
DC Resistance Rated Current
(max.)
(max.)
L-07W82NJV4T
L-07WR10JV4T
L-07WR11JV4T
L-07WR12JV4T
82.0 nH
100.0 nH
110.0 nH
120.0 nH
+/-5%, +/-10%
+/-5%, +/-10%
+/-5%, +/-10%
+/-5%, +/-10%
16@150 MHz
16@150 MHz
14@150 MHz
14@150 MHz
39
36
35
35
N/A
N/A
N/A
N/A
1.5 GHz
1.3 GHz
1.2 GHz
1.1 GHz
1.250
Ω
2.520
Ω
2.660
Ω
2.660
Ω
100 mA
100 mA
100 mA
100 mA
0603 i
nDuCTanCe
R
ange
/ e
leCTRiCal
C
HaRaCTeRiSTiCS
Part Number
(Standard Tol.)
Inductance
@ L/Q Freq.
L/Q Test
Freq.
Availiable Tolerances
@ L/Q Freq.
Q (min.)
@ L/Q Freq.
SRF (min.)
DC Resistance
(max.)
Rated Current
(max.)
L-14W1N6SV4E
L-14W1N8SV4E
L-14W2N0SV4E
L-14W3N3SV4E
L-14W3N6SV4E
L-14W3N9SV4E
L-14W4N3SV4E
L-14W4N7SV4E
L-14W5N1JV4E
L-14W5N6JV4E
L-14W6N8JV4E
L-14W7R5JV4E
L-14W8N2JV4E
L-14W8N7JV4E
L-14W10NJV4E
L-14W11NJV4E
L-14W12NJV4E
L-14W15NJV4E
L-14W18NJV4E
L-14W22NJV4E
L-14W27NJV4E
L-14W33NJV4E
L-14W39NJV4E
L-14W47NJV4E
L-14W51NJV4E
L-14W56NJV4E
L-14W68NJV4E
L-14W72NJV4E
L-14W82NJV4E
L-14WR10JV4E
L-14WR12JV4E
L-14WR15JV4E
L-14WR18JV4E
L-14WR22JV4E
L-14WR27JV4E
L-14WR33JV4E
L-14WR39JV4E
L-14WR47JV4E
26
1.6 nH
1.8 nH
2.0 nH
3.3 nH
3.6 nH
3.9 nH
4.3 nH
4.7 nH
5.1 nH
5.6 nH
6.8 nH
7.5 nH
8.2 nH
8.7 nH
10.0 nH
11.0 nH
12.0 nH
15.0 nH
18.0 nH
22.0 nH
27.0 nH
33.0 nH
39.0 nH
47.0 nH
51.0 nH
56.0 nH
68.0 nH
72.0 nH
82.0 nH
100.0 nH
120.0 nH
150.0 nH
180.0 nH
220.0 nH
270.0 nH
330.0 nH
390.0 nH
470.0 nH
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
250 MHz
200 MHz
200 MHz
200 MHz
200 MHz
150 MHz
150 MHz
150 MHz
150 MHz
150.0 nH
100 MHz
100 MHz
100 MHz
100 MHz
100 MHz
100 MHz
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±0.3 nH
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±0.2 nH, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±2%, ±5%, ±10%
±5%, ±10%
±5%, ±10%
±5%, ±10%
14
16
16
17
20
22
22
20
18
16
30
30
30
30
31
33
35
35
38
38
40
43
43
40
40
40
40
35
35
35
35
35
30
30
30
25
24
23
7.0 GHz
6.9 GHz
6.9 GHz
6.1 GHz
6.0 GHz
5.9 GHz
5.8 GHz
5.8 GHz
5.4 GHz
5.0 GHz
4.6 GHz
4.7 GHz
4.8 GHz
4.6 GHz
4.0 GHz
4.0 GHz
4.0 GHz
3.1 GHz
3.0 GHz
3.0 GHz
2.8 GHz
2.3 GHz
2.2 GHz
2.0 GHz
1.9 GHz
1.9 GHz
1.7 GHz
1.7 GHz
1.7 GHz
1.4 GHz
1.3 GHz
1.0 GHz
1.0 GHz
1.0 GHz
1.0 GHz
900 MHz
750 MHz
700 MHz
0.080
Ω
0.080
Ω
0.080
Ω
0.080
Ω
0.080
Ω
0.080
Ω
0.060
Ω
0.110
Ω
0.110
Ω
0.110
Ω
0.110
Ω
0.110
Ω
0.100
Ω
0.120
Ω
0.130
Ω
0.086
Ω
0.130
Ω
0.170
Ω
0.170
Ω
0.220
Ω
0.220
Ω
0.220
Ω
0.250
Ω
0.280
Ω
0.300
Ω
0.310
Ω
0.340
Ω
0.490
Ω
0.540
Ω
0.630
Ω
0.650
Ω
0.920
Ω
1.25
Ω
1.70
Ω
1.80
Ω
3.60
Ω
5.30
Ω
5.60
Ω
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
700 mA
600 mA
600 mA
600 mA
600 mA
600 mA
600 mA
600 mA
400 mA
400 mA
400 mA
300 mA
280 mA
240 mA
200 mA
170 mA
150 mA
100 mA
100 mA
www.johansontechnology.com
ADI 工业技术
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
