RF Inductors

DIRECT RF (Radio Frequency) Inductors of Surface Mount Device (SMD) includes following types:
air core RF inductors flat and non-flat top, multilayer RF inductors beads and chip type, and RF wirewound inductors molded-type and chip open-type. Commonly apply on notebook computer, disc drive unit(CD/DVD), inkjet printer, hard disk drive, copying machine, display monitor, gaming machine, color TV, video tape recorder, DVD player, video camera, digital still camera, car electronics, and lowest EMI, etc..

RF INDUCTORS - Download Entire RF Inductor Catalogue.

Wirewound Inductors

Thumbnail Description
(TREC) RF Chip Wire Wound Inductors
Molded Type Wirewound Chip Inductors feature high resistance to heat, humidity, mechanical shocks and presser. Accurate dimensions for automatically surface mounted. Direct TREC Series is primarily designed for chip narrow pad, high current, molded type, wire wound inductors and offers improved performance in the same compact case size. Product conforms to the RoHS directive and Lead-free. The TREC series chip inductor can be customed designs for tighter tolerances on request.
(TREC) Series - PDF
(TREM) RF High SRFs Inductors
(TREM) RF High SRFs series high reliable wire would chip inductors for communication, equipment, instrument, video & audio have been developed in response to the trend toward higher density mounting of parts in electric circuits. Direct TREM Series is primarily designed for chip narrow pad, high SRFs, molded type, wire wound inductors and offers improved performance in the same compact case size.
(TREM) Series - PDF
(TRAD) Surface Mount Air Core Inductors
Direct's ultra-miniature single layer coil has two advantages. Firstly, like all air core coils, it is free from iron losses and the non-linearity. Secondly, single layer coils have the additional advantage of low self-capacitance and thus high self-resonant frequency. Air Coils is known as "Spring Coils". Direct manufactures all types of air coils inductors.
(TRAD) Series - PDF
(TRAM) Surface Mount Spring Inductors
The latest range of air core surface mount spring coils from Direct is fully compliant with RoHS legislation and available immediately in full production volumes. The TRAM series provides a cost effective and miniaturised alternative to the earlier version. The wire-wound construction with a miniature core is ideal for high frequency applications. These new SMD coils measure 1.8 x 2.0 mm with a low 2.0 mm profile, which combined with a mould-sealed surface, makes them particularly suitable for high-density mounting.
(TRAM) Series - PDF
(TRWL) Wire Wound Ceramic Chip Inductors
Direct TRWL series is a wire wound and ceramic technology that offers the highest usable frequency range, highest current carrying capability, and the best Q factor of the three technologies. The combination of these three advantages ensure that design engineers will have the right product for many more high frequency applications than most competitors. High frequency inductors are specifically used for their frequency dependent properties. Depending on the technology, size and inductance value, the inductor will pass a certain desired range of frequencies, but will block or attenuate frequencies above the desired range. This eliminates high frequency noise or interference from communications signals.
(TRWL) Series - PDF
(TRCM) Wire Wound SMD Inductors
Molded-Type Chip RF Wirewound Inductors feature high resistance to heat, humidity, mechanical shocks and pressures. Miniaturisation of today's electrical and electronic devices requires component manufacturers to increase the performance of components without increasing footprint. Direct TRCM series utilities wirewound technology that offers wide Pad inductor with the highest SRF carrying capability, highest usable frequency range, and the best Q factor of the narrow pad TREM and TREC series.
(TRCM) Series - PDF
(TR4308I) RFID Coils Series
Direct TR4308I transponder coil series is specified for RFID applications for the best performing designed at 125 kHz. The TR4308I covers a wide range of electrical performances and offers better sensitivity, greater read distance and higher SRF than other coils its size. Radio Frequency Identification (RFID) is the system of using radio signals to send information identifying a particular situation or item. Direct TR4308I is suited for wireless data transmission in low frequency RFID products, such as immobilizers, TPMS, keyless entry. Other industrial applications include access control and tracking devices.
(TR4308I) Series - PDF

Thin Film & Multilayer Inductors

Thumbnail Description
(TRAL) Thin-Film Inductors
Direct TRAL chip thin-film inductors provide reliable protection against challenging EMI problems in high frequency filtering applications. This miniature wirewound inductor features a low seated height that stands only 0.23mm above the circuit board. It protects sensitive electronic circuitry and ensures high performance operation in a wide range of compact devices that are shrinking ever smaller in physical size. TRAL series uses a thin-film technology for high reliability and precision tolerances to 1% or ±0.1nH. The TRAL thin-film inductor series is available in 0603, 0402, and 0201 sizes, in inductance values from 0.1 to 100nH, in tolerances down to 0.1nH or 1%, and with SRF (self-resonant frequency) tightly controlled.
(TRAL) Series - PDF
(TRMA) Multilayer Ferrite Beads Chip Inductors
Direct TRMA series multilayer ferrite bead inductor is one popular high current version of Direct chips products. Ceramic materials and process technologies have allowed Direct to lower the DC resistance of its chip ferrite beads, increasing rated current to create the TRMA series. With a maximum current rating of up to 6A and a wide operating temperature range of between -55°C and +125°C, the TRMA series is ideally suited to applications in harsh environments. The series comes in 0402 size packaging (1 x 0.5 x 0.5 mm), for designers seeking to reduce board space without performance degradation. Low DC resistance also helps reduce power consumption for battery-powered applications.
(TRMA) Series - PDF
(TRMB) RF Multilayer Bead Inductors
Direct Electronics has introduced the TRMB Series, a family of twelve multilayer chip bead inductors offering high impedance. The TRMB Bead series is a multilayer technology with good overall characteristics in a cost effective package. In addition, TRMB parts offer a high-performance noise-filtering capability over a wide range of high frequencies. In systems that currently use multiple narrow-band inductors to cover a wide frequency range, the TRMB can provide the same function in a single chip, reducing component count and board area. The TRMB multilayer inductor series is available in 1812, 1806, 1210, 1206, 0805, 0603, and 0402 sizes in three catalogs, standard, low profile, and High Speed Signals. This product provides a good addition of electrical performance and low cost.
(TRMB) Series - PDF
(TRMF) RF Multilayer Ceramic Inductors
Ceramic materials and process technologies have allowed Direct to add magnetics portfolio with a new series of multilayer high-frequency ceramic inductors. The Direct TRMF series inductors are aimed at signal shaping and RF filtering applications in a wide range of electronic systems. Target end products include remote controls, high-end video processing equipment, set-top boxes, cell phones, pagers, keyless entry systems, wireless and wireline networks, and cable modems. Standard inductance options for the TRMF series range from 1 nH to 100 nH. Available tolerances are ±0.3nH, ±5%, and ±10%. Maximum DC resistance (DCR) ranges from 0.1Ω to 2.5Ω depending on inductance. In a space-saving surface-mount 0402 package measures (1 x 0.5 mm) and with 2-mil (0.5 mm) height profile. 0402, 0603, and 0805 package size are available.
(TRMF) Series - PDF
(TRMI) Chip Multilayer Ferrite Inductors
The TRMI devices utilize closed magnetic circuit construction to avoid crosstalk. These are suitable for EMI reduction on DC power lines and low speed signal lines where the smaller packaging reduces board space. Conform to the RoHS directive and Lead-free. Package of multilayer Ferrite TRMI chip is suitable for automatic pick and place equipment and is mounted in a surface mount package which assures mechanical stability and excellent lead coplanarity. Direct TRMI series is a multilayer ferrite technology with good overall characteristics in a cost effective package. The TRMI multilayer inductor series is available in 0603, 0805, and 1206 sizes. Inductance values range from 10 to 33000nH, and tolerances are as tight as ±10%.
(TRMI) Series - PDF