OverviewAll product unitsProduct unitPassive ComponentsProduct groupSignal & CommunicationsProduct familyRF InductorsProduct seriesWE-RFI Ferrite SMT Inductor

WE-RFI Ferrite SMT Inductor EXTENDED

WE-RFI Ferrite SMT Inductor
 Size Dimen­sionsL
(mm)
W
(mm)
H
(mm)
Mount
NEW 0402 1 0.55 0.55 SMT
NEW 0603 1.65 1.1 0.9 SMT
0805 2 1.25 1.2 SMT
1008 2.5 2 1.6 SMT

Characteristics

  • High inductances
  • Recommended soldering: Reflow
  • Custom designs on request
  • AEC-Q200 Grade 3 (−40°C to +85°C)
  • Operating temperature: –40 °C to +85 °C

Applications

  • Especially developed for RF-applications
  • RFID
  • Low frequency radio applications (keyless)

Products

All
0402
0603
0805
1008
Order Code Data­sheet Simu­lation DownloadsL
(nH)
Tol. LTest Condition LQmin.
(%)
QRDC max.
(mΩ)
IR
(mA)
fres
(MHz)
Design Kit Samples
NEW7447650120SPEC
8 files 20 ±5% 7.9 MHz 11 11 25 1080 7720
NEW7447650130SPEC
8 files 30 ±5% 7.9 MHz 11 11 35 900 3800
NEW7447650133SPEC
8 files 33 ±5% 7.9 MHz 11 11 35 900 3875
NEW7447650136SPEC
8 files 36 ±5% 7.9 MHz 11 11 40 850 3875
NEW7447610139SPEC
8 files 39 ±5% 7.9 MHz 12 12 42 1170 2320
NEW7447610168SPEC
8 files 68 ±5% 7.9 MHz 13 13 50 1050 1925
NEW7447650177SPEC
8 files 77 ±5% 7.9 MHz 11 11 90 640 2980
NEW7447650210SPEC
8 files 100 ±5% 7.9 MHz 12 12 130 550 2955
NEW7447610211SPEC
8 files 110 ±5% 7.9 MHz 13 13 78 750 1925
NEW7447650212SPEC
8 files 120 ±5% 7.9 MHz 12 12 110 575 2955
NEW7447610215SPEC
8 files 150 ±5% 7.9 MHz 13 13 90 720 1885
NEW7447650215SPEC
8 files 150 ±5% 7.9 MHz 12 12 130 545 2590
NEW7447650218SPEC
8 files 180 ±5% 7.9 MHz 12 12 160 470 2955
NEW7447610220SPEC
8 files 200 ±5% 7.9 MHz 13 13 105 700 1730
NEW7447650222SPEC
8 files 220 ±5% 7.9 MHz 12 12 220 390 2170
NEW7447610224SPEC
8 files 240 ±5% 7.9 MHz 13 13 180 490 1345
NEW7447610227SPEC
8 files 270 ±5% 7.9 MHz 13 13 165 480 1540
NEW7447650227SPEC
8 files 270 ±5% 7.9 MHz 12 12 260 370 2015
NEW7447610236SPEC
8 files 360 ±5% 7.9 MHz 13 13 185 470 1040
NEW7447650236SPEC
8 files 360 ±5% 7.9 MHz 12 12 375 320 1565
NEW7447610242SPEC
8 files 420 ±5% 7.9 MHz 13 13 255 425 1110
NEW7447650242SPEC
8 files 420 ±5% 7.9 MHz 12 12 460 270 1810
744760247ASPEC
9 files 470 ±5% 25.2 MHz 45 500 500 375744762ARFI
NEW7447650247SPEC
8 files 470 ±5% 7.9 MHz 12 12 510 260 1600
NEW7447650253SPEC
8 files 530 ±5% 7.9 MHz 12 12 615 230 1600
744760256ASPEC
9 files 560 ±5% 25.2 MHz 45 550 450 340744762ARFI
NEW7447610256SPEC
8 files 560 ±5% 7.9 MHz 13 13 270 390 915
NEW7447650259SPEC
8 files 590 ±5% 7.9 MHz 12 12 670 220 1370
NEW7447610260SPEC
8 files 600 ±5% 7.9 MHz 13 13 380 330 1000
744760268ASPEC
9 files 680 ±5% 25.2 MHz 35 850 400 188744762ARFI
NEW7447650270SPEC
8 files 700 ±5% 7.9 MHz 11 11 1125 160 1565
NEW7447650277SPEC
8 files 770 ±5% 7.9 MHz 12 12 1250 155 1240
744760282ASPEC
9 files 820 ±5% 25.2 MHz 35 1050 300 215744762ARFI
NEW7447610282SPEC
8 files 820 ±5% 7.9 MHz 13 13 450 300 830
744760310ASPEC
9 files 1000 ±5% 25.2 MHz 35 1050 180 200744762ARFI
NEW7447610310SPEC
8 files 1000 ±5% 7.9 MHz 13 13 700 230 680
744760312ASPEC
9 files 1200 ±5% 7.96 MHz 15 1200 150 200744762ARFI
744762312ASPEC
9 files 1200 ±5% 7.96 MHz 20 1300 230 280744762ARFI
744760315ASPEC
9 files 1500 ±5% 7.96 MHz 15 1450 130 200744762ARFI
744762315ASPEC
9 files 1500 ±5% 7.96 MHz 20 1650 220 250744762ARFI
NEW7447610315SPEC
8 files 1500 ±5% 7.9 MHz 13 13 1070 200 605
744760318ASPEC
9 files 1800 ±5% 7.96 MHz 15 2000 120 120744762ARFI
744762318ASPEC
9 files 1800 ±5% 7.96 MHz 20 2200 210 200744762ARFI
744760322ASPEC
9 files 2200 ±5% 7.96 MHz 15 1750 110 110744762ARFI
744762322ASPEC
9 files 2200 ±5% 7.96 MHz 20 2350 200 160744762ARFI
NEW7447610322SPEC
8 files 2200 ±5% 7.9 MHz 13 13 400 350 110
744760327ASPEC
9 files 2700 ±5% 7.96 MHz 15 1750 100 100744762ARFI
744762327ASPEC
9 files 2700 ±5% 7.96 MHz 20 2600 195 130744762ARFI
744760333ASPEC
9 files 3300 ±5% 7.96 MHz 15 2000 210 70744762ARFI
744762333ASPEC
9 files 3300 ±5% 7.96 MHz 20 2850 185 80744762ARFI
NEW7447610333SPEC
8 files 3300 ±5% 7.9 MHz 14 14 950 220 110
744760339ASPEC
9 files 3900 ±5% 7.96 MHz 15 2150 200 60744762ARFI
744762339ASPEC
9 files 3900 ±5% 7.96 MHz 20 4000 180 50744762ARFI
744760347ASPEC
9 files 4700 ±5% 7.96 MHz 15 1900 180 50
744762347ASPEC
9 files 4700 ±5% 7.96 MHz 20 4300 175 45744762ARFI
NEW7447610347SPEC
8 files 4700 ±5% 7.9 MHz 14 14 1125 200 67
744760356ASPEC
9 files 5600 ±5% 7.96 MHz 15 2200 160 45744762ARFI
744762356ASPEC
9 files 5600 ±5% 7.96 MHz 20 2600 170 42
NEW7447610356SPEC
8 files 5600 ±5% 7.9 MHz 14 14 1055 195 62
744762368ASPEC
9 files 6800 ±5% 7.96 MHz 20 2800 165 39
NEW7447610368SPEC
8 files 6800 ±5% 7.9 MHz 14 14 1380 170 52
744760382ASPEC
9 files 8200 ±5% 7.96 MHz 15 2400 120 40744762ARFI
744762382ASPEC
9 files 8200 ±5% 7.96 MHz 20 3050 160 36
NEW7447610382SPEC
8 files 8200 ±5% 7.9 MHz 14 14 1550 150 46
744760410ASPEC
9 files 10000 ±5% 2.52 MHz 15 3600 80 40744762ARFI
744762410ASPEC
9 files 10000 ±5% 2.52 MHz 15 3500 150 33
NEW7447610410SPEC
8 files 10000 ±5% 2.5 MHz 14 14 1700 160 40
744762415ASPEC
9 files 15000 ±5% 2.52 MHz 15 4000 130 26744762ARFI
NEW7447610415SPEC
8 files 15000 ±5% 2.5 MHz 13 13 3900 90 30
744762418ASPEC
9 files 18000 ±5% 2.52 MHz 15 4500 120 24744762ARFI
744762422ASPEC
9 files 22000 ±5% 2.52 MHz 15 5000 110 22744762ARFI
744762427ASPEC
9 files 27000 ±5% 2.52 MHz 15 6000 95 21744762ARFI
744762433ASPEC
9 files 33000 ±5% 2.52 MHz 15 6500 85 20744762ARFI
744762439ASPEC
9 files 39000 ±5% 2.52 MHz 15 8500 60 18744762ARFI
744762447ASPEC
9 files 47000 ±5% 2.52 MHz 15 14000 45 17744762ARFI
Order Code Data­sheet Simu­lation
NEW7447650120SPEC
NEW7447650130SPEC
NEW7447650133SPEC
NEW7447650136SPEC
NEW7447610139SPEC
NEW7447610168SPEC
NEW7447650177SPEC
NEW7447650210SPEC
NEW7447610211SPEC
NEW7447650212SPEC
NEW7447610215SPEC
NEW7447650215SPEC
NEW7447650218SPEC
NEW7447610220SPEC
NEW7447650222SPEC
NEW7447610224SPEC
NEW7447610227SPEC
NEW7447650227SPEC
NEW7447610236SPEC
NEW7447650236SPEC
NEW7447610242SPEC
NEW7447650242SPEC
744760247ASPEC
NEW7447650247SPEC
NEW7447650253SPEC
744760256ASPEC
NEW7447610256SPEC
NEW7447650259SPEC
NEW7447610260SPEC
744760268ASPEC
NEW7447650270SPEC
NEW7447650277SPEC
744760282ASPEC
NEW7447610282SPEC
744760310ASPEC
NEW7447610310SPEC
744760312ASPEC
744762312ASPEC
744760315ASPEC
744762315ASPEC
NEW7447610315SPEC
744760318ASPEC
744762318ASPEC
744760322ASPEC
744762322ASPEC
NEW7447610322SPEC
744760327ASPEC
744762327ASPEC
744760333ASPEC
744762333ASPEC
NEW7447610333SPEC
744760339ASPEC
744762339ASPEC
744760347ASPEC
744762347ASPEC
NEW7447610347SPEC
744760356ASPEC
744762356ASPEC
NEW7447610356SPEC
744762368ASPEC
NEW7447610368SPEC
744760382ASPEC
744762382ASPEC
NEW7447610382SPEC
744760410ASPEC
744762410ASPEC
NEW7447610410SPEC
744762415ASPEC
NEW7447610415SPEC
744762418ASPEC
744762422ASPEC
744762427ASPEC
744762433ASPEC
744762439ASPEC
744762447ASPEC
Samples
Order Code Data­sheet Simu­lation DownloadsL
(nH)
Tol. LTest Condition LQmin.
(%)
QRDC max.
(mΩ)
IR
(mA)
fres
(MHz)
Design Kit Samples

What is the Quality Factor Q?

The quality factor Q is an essential characteristic parameter and one of the first creterias that every RF engineer should take into account. The Q factor is given either as minimum or as typical value at a defined frequency point. In the case of Würth Elektronik, the Q factor is given as the minimum value in order to guarantee customers a reliable minimum level.

Basically, the Q factor is the ratio between the inductive reactance XL and the losses RS and is an indicator of how ideal an inductor is. For inductors with air or ceramic cores, the resistance RS is mainly due to the resistivity of the conductor in the inductor device. A higher Q factor means less losses in the component.

Self Resonant Frequency

Because the winding structure of any coil of wire will exhibit some capacitance, the inductor will serve as a parallel resonant tank circuit with an associated self-resonance frequency (SRF). As with conventional inductors, SRF indicates up to which frequency the inductor behaves as an inductor.

Exactly at the SRF the inductor with its parasitic capacitance behaves as a resonance circuit with an almost infinite high impedance, only circuit losses limit the high value of the impedance. Beyond the SRF the “inductor” behaves like a capacitor

Increasing the inductance and/or the parasitic capacitance lowers the SRF, and vice versa. This is the reason why the higher the inductance value, the lower the SRF.

In case of choke applications in which inductors are used, the best signal blocking occurs shortly below the SRF, where the impedance is very high and thus the attenuation reaches its maximum. For filter or impedance-matching applications, it is more important to have constant inductance in the relevant frequency range, which means the SRF of the inductor should be well above the operating frequency of the circuit.

Rated Current in high frequency application

The rated current is specified as the maximum DC current (A or mA) that causes a defined temperature rise (i.e. ΔT = 40 K). The temperature rise plus the ambient temperature must not exceed the maximum operating temperature. For high current applications, please select the specific air core inductors: WE-KI HC, WE-ACHC and WE-CAIR.

RF inductors and Antenna Matching

How Antenna Matching works

With the help of the Smith chart, the complex antenna feed point impedance, consisting of resistive and reactive values, can be represented graphically. In a matched antenna, the impedance at the operating frequency is close to the middle of the Smith chart and therefore close to the impedance of 50 Ω. This can be achieved by using RF inductors and RF capacitors. A pi matching network is particularly useful for this purpose, since it can be used flexibly for antenna matching from almost any other impedance. In practice, antenna matching works through iterative steps.

In addition to the WE-MCA Antennas, we offer our customers a development-accompanying antenna service. We support from the antenna selection over the antenna placement up to the antenna matching.

Website: www.we-online.com/antenna-matching

E-Mail: antenna.matching@we-online.com

We are also offering an Antenna Matching Design Kit that contains all the components needed for your antenna matching. This Design Kit with order code 748001, contains chip antennas WE-MCA, multilayer ceramic inductors WE-MK size 0402, high frequency chip capacitors WCAP-CSRF in size 0402 and RF coaxial cables WR-CXARY working up to 18 GHz

Assortments

Articles from this product series can be found in the following assortments:

Videos

Würth Elektronik Webinar: Signal interface filters - effectiveness under real conditions