RF Inductors

The inductance of Würth Elektronik RF inductors can be characterized over a wide frequency range. The characterization of performance is necessary for application like RF filters, VCO’s, phase shifters and delay networks. Furthermore, RF inductors can be implemented to reduce RF signals in certain circuit paths. There are many characteristics that you have to pay attention to when selecting components for RF applications because there are no ideal components and RF inductors are no exception. Because of these parasitic effects, the characteristics of the inductor are influenced by losses and frequency dependency. The self-resonance frequency (SRF) is one parameter which determines the bandwidth and therefore the frequency behavior. The SRF is defined by various construction technology and the frequency dependency of parasitic capacitance of the land pattern. Above the SRF the inductor cannot be implemented as an inductor because of the predominance of the parasitic capacitive characteristics.

Würth Elektronik offers RF products in two types: ceramic and ferrite. Their ceramic inductors include wire wound, thinfilm and multilayer. Their ferrite inductors have high current standards, which are for high frequency. The different characteristics and applications are based on the several various construction technology of the inductors. The following inductors below are available from Würth Elektronik:

• Wire Wound: Based on the wire wound technology, the inductors distinguish a high quality factor and a high current carrying capacity. A benefit to these is low DC resistance.
  • WE-KI ceramic core inductors: Offer excellent Q factor and the highest possible self-resonant frequencies up to 12.5 GHz. They are available in sizes 0402A, 0603A, 0603C, 0805A, 0805C, and 1008A.
  • WE-RFI and WE-RFH ferrite core inductors: Similar products with the exception that the WE-RFH has a higher current handling capability and is available in only one size (1008), while the WE-RFI series are available in two sizes (0805A and 1008A).
• Multilayer: The WE-MK series meet the demand for the proceeding miniaturization and, therefore, are available in small package sizes of 0201, 0402, 0402A, 0603, and 0603A. They are thermally stable and do not show any variation in inductance over a large temperature range.
• Thin Film: The WE-TCI series can be characterized with extreme accuracy, which results in a very tight tolerance product. Tolerances of about 2% and 1% are available upon request so it is possible to recognized precise application behavior. They are available in 0201 and 0402 sizes.
• Air Coil: The WE-CAIR series are characterized by very high quality factors, low frequency range (Q > 100), and high termperature stability with a very high resonance frequency and a guaranteed greater rated current compared to other RF inductors. They are available in sizes 1322, 3136, 1340, 4248, and 3168.