Document 117-1
Surface Mount Wideband RF Transformers
Available in a variety of impedance versions, Coilcraft’s
WBT Series chip transformers provide wide band pass
performance in a small surface mount package.
The transformers are built on an 1812 size ferrite body
with a ceramic base. They feature 50 V isolation and a
1/4 Watt RF input power rating. The top is a high
temperature material that creates a flat surface for auto
insertion. The parts are packaged in tape and reel for
easy dispensing.
Applications include impedance matching, voltage or
current transformation, DC isolation, balanced/unbal-
anced mixing, matching, power splitting, coupling and
signal inversion.
To request free evaluation samples, contact Coilcraft or
visit www.coilcraft.com.
1:1 Transformers
Part
Inductance2 Testfrequency Imp. ratio DCRmax
IDC
(mA)
Isolation
(Vrms)
Insertion Bandwidth Color
number1
(µH)
(MHz)
pri:sec
(Ohms)
loss (dB)
(MHz)
dot
1812WBT-1L_
1812WBT-2L_
1812WBT-3L_
1812WBT-4L_
1812WBT-5L_
14
10
10
50
50
50
1 : 1
1 : 1
1 : 1
1 : 1
1 : 1
4.8
1.8
0.7
0.3
0.15
200
400
500
700
700
50
50
50
50
50
<1
0.340
0.800
–
22
60
Yellow
Green
White
Orange
Red
5.3
<1
–
1.25
0.220
0.090
<1
<1
<1.5
4–200
11
–
480
48
–
645
1.5:1 Transformers
Inductance(µH)2
DCR max (⏲)
Part
Test freq. Imp. ratio
IDC
Isolation Insertion Bandwidth Color
number1
pri
sec
(MHz)
pri:sec
pri
sec
(mA)
(Vrms) loss (dB)
(MHz)
1.3 100
2.75
7.2
38
dot
1812WBT1.5-1L_
1812WBT1.5-2L_
1812WBT1.5-3L_
1812WBT1.5-4L_
5.0
3.3
10
10
10
10
1.5 :1
1.5 :1
1.5 :1
1.5 :1
1.05
0.74
0.43
0.18
0.87
0.58
0.34
0.14
400
500
500
700
50
50
50
50
0.5
–
Red
2.5
1.6
0.5
–
135 Orange
1.0
0.144
0.6
0.75
2.25
–200
Yellow
Green
0.090
–535
2:1 Transformers
Inductance(µH)2
DCR max (⏲)
Part
Test freq. Imp. ratio
IDC
(mA)
Isolation Insertion Bandwidth Color
(Vrms) loss (dB) (MHz) dot
number1
pri
sec
(MHz)
pri:sec
pri
sec
1812WBT2-1L_
1812WBT2-2L_
1812WBT2-3L_
1812WBT2-4L_
13.80
5.850
2.60
6.90
10
10
10
50
2 :1
2 :1
2 :1
2 :1
4.6
3.2
200
400
600
700
50
50
50
50
<1.5
<1.5
<1.5
<1.5
0.800
2.2 65
105
200
–
23 Brown
2.925
1.30
1.25
0.52
0.27
0.95
0.42
0.23
–
Red
4
–
Orange
Yellow
0.910
0.455
11
–
1. When ordering, please specify termination and packaging codes:
1812WBT-1.5-4LC
Termination: L = RoHS compliant gold over nickel over moly-manganese
Special order: T = RoHS tin-silver-copper (95.5/4/0.5) or S = non-RoHS tin-lead (63/37).
C = 7″ machine-ready reel. EIA-481 embossed plastic tape (600 parts per full reel).
Packaging:
B = Less than full reel. In tape, but not machine ready. To have a leader and trailer added ($25 charge), use code letter C instead.
D = 13″ machine-ready reel. EIA-481 embossed plastic tape. Factory order only, not stocked (2200 parts per full reel).
2. Inductance is per winding
3. Operating temperature range -40°C to +85°C.
4. Electrical specifications at 25°C.
Specifications subject to change without notice.
Please check our website for latest information.
Document117-1 Revised03/23/06
© Coilcraft, Inc. 2006