Pulse Introduces Five New Series of SMT Drum Core Power Inductors; Inductors Meet Requirements for Wide Range of DC-to-DC and Filtering Applications.

SAN DIEGO -- Pulse, a Technitrol (NYSE:TNL) Company, one of the world's largest electronic component manufacturers and a leader in passive, magnetics-based components, introduces five new series of unshielded and shielded surface mount (SMT) drum core power inductors for a total of 96 different parts. The inductors cover a large range of inductance values from sub microhenry up to hundreds of microhenries, at low ampere currents, in a variety of sizes to meet the broad range of local DC-to-DC converter and filtering applications.

The five new series of SMT drum core power inductors include:

--PF0504 unshielded inductor series: 15 values from 0.68 microhenry 20 Amps to 150 microhenries 2 Amps; size is 0.73 x 0.6 x 0.45 inch.

--PF0580 unshielded inductor series: 22 values from 1 microhenry 3.1 Amps to 65 microhenries 0.41 Amp; size is 0.185 x 0.165 x 0.137 inch.

--PF0581 unshielded power inductor series: 22 values from 10 microhenries 2.5 Amps to 560 microhenries 0.32 Amp; size is 0.406 x 0.367 x 0.174 inch.

--PF0601 shielded power inductor series: 22 values from 2.9 microhenries 2 Amps to 330 microhenries 0.19 Amp; size is 0.272 x 0.256 x 0.118 inch.

--PF0560 shielded power inductor series: 15 values from 1.5 microhenries 6.5 Amps to 330 microhenries 0.52 Amp; size is 0.409 x 0.406 x 0.157 inch.

"Drum core" is used to describe the shape of the ferrite core used in these power inductors, and it differentiates them from other types of inductors such as toroidal, flat coil, or planar. There are two types of drum core inductors, unshielded and shielded.

The unshielded drum core has a narrow center rod with a flat disc on each end. The inductor wire is wound on the rod between the discs. The inductor is an energy storage device which stores energy in an air gap in the flux path of the inductor. For the unshielded drum core inductor, this air gap is between the two end discs. The flux path is through the center rod, outwards through one disc, through the air gap around to the outside of the other disc, and inwards through the second disc. The unshielded drum core is a lower cost technology and the larger energy storage air gap allows it to support higher peak currents without saturation effects.

In the shielded drum core inductor, an additional ferrite cylinder is located around the outside of the two discs and guides the flux between the discs through the cylinder. The discrete air gap is the combination of the gaps between each end disc and the ferrite cylinder. Because the additional ferrite cylinder keeps the flux in a controlled path, shielded drum core inductors are better for applications where the stray flux of the unshielded drum core may interfere with nearby noise-sensitive electronics or where electromagnetic interference (EMI) is a concern. The shielded drum core inductor has a higher inductance for the same number of wire turns than the unshielded inductor due to the smaller air gap and higher permeability of the ferrite cylinder.

Applications that use drum core inductors include, but are not limited to:

--Catalog power modules

--Computer equipment - notebook computers, hard disk drives, video graphic cards, small printers

--Telecom equipment - modems, mobile phones, set-top-boxes

--Consumer electronics - game stations, digital cameras, PDAs, LCD displays and TVs, CD players

It is important to consider several electrical specifications when selecting a drum core inductor. First select the direct current resistance (DCR) value, then match the rest of the electrical specifications to the requirements of the application. For the DCR value, generally smaller is better because direct current resistance is unwanted as part of the input power is consumed in heat and not transferred to the application efficiency of the DC converter. The application will determine the size and height constraints, mounting method (surface mount device or through-hole) and the need for an unshielded or shielded drum core.

When the drum core is used as an output choke in a DC-to-DC converter, the purpose of this choke is to limit the current ripple on the output of the converter. The inductance, switching frequency, and output current will determine the current ripple. With the inductance requirement determined, the next step is to identify the smallest inductor that has the required inductance at the required rated current. In general, the rated current at a particular inductance will increase with inductor size.

Inductance at rated, or peak, current is a critical parameter and is determined by the application. The rated current is the minimum of heating or saturation current. Some drum core inductors, especially the unshielded drums with the large air gap, have significantly higher saturation current than heating current. These inductors are particularly suited to applications that allow a relatively large current ripple where the peak current will be higher than the root mean square (RMS) current.

When it is not possible to achieve the required inductance at the rated current from the drum-core product range, the next step is to examine alternative technologies such as larger toroidal inductors, bead, flat coil, or planar inductors. Pulse's Power Magnetics Catalog, which can be found on the Pulse website, can serve as a guide.

Thermal performance is another criterion to consider in selection. Both unshielded and shielded drum inductors in these new Pulse inductor series have been designed to work in an ambient temperature range of minus 40 degrees Celsius to 125 degrees Celsius. The electrical performances given are for an ambient temperature of 25 degrees Celsius. This operating temperature range is important because in certain applications, such as portable products with small enclosures, the temperature to which the equipment is exposed can change significantly.

All parts in these series are RoHS compliant and can support a peak reflow soldering temperature of 260 degrees Celsius. They also meet UL94 V0 standards.

The price range of Pulse's drum core power inductors in these series are between $0.10 and $0.20, depending on the part and quantity. They come in trays or tape-and-reel packaging. Lead-time is six to eight weeks. Contact Pulse directly for samples. Detailed specifications are available on datasheets PC2005_10 (http://www.pulseeng.com/pdf/PC2005_10.pdf) for the PF0504 series, PC2005_02 (http://www.pulseeng.com/pdf/PC2005_02.pdf) for the PF0580 series, PC2005_05 (http://www.pulseeng.com/pdf/PC2005_05.pdf) for the PF0581 series, PC2005_18 (http://www.pulseeng.com/pdf/PC2005_18.pdf) for the PF0601 series, and PC2005_22 (http://www.pulseeng.com/pdf/PC2005_22.pdf) for the PF0560 series located on the Pulse Web.

About Pulse

Headquartered in San Diego, California, Pulse, a Technitrol (NYSE:TNL) Company, is one of the largest magnetic component manufacturers in the world. Pulse primarily serves OEMs in the data networking, telecommunications, high-speed Internet access, power conversion, military/aerospace, and consumer electronics industries. Recognized as experts in interference (noise) reduction, miniaturization, power management, and signal conversion, Pulse offers an extensive line of custom and standard passive magnetic solutions for OEMs in commercial as well as consumer industries. An ISO 9000 registered manufacturer, Pulse is fully engaged in joint development programs with key customers to ensure they receive high-performance, high-quality, and high-reliability products at competitive prices. Pulse is a member of and actively participates in IEEE, ANSI, T1/E1, and the DSL Forum.

In North America, contact Pulse's worldwide headquarters in the United States at 858-674-8100. The Pulse European offices are located in the United Kingdom and may be reached at [phone], and its Asian offices in Singapore can be reached at [phone]. For more information, visit the Pulse Web site at www.pulseeng.com.

Copyright (C)2005 Pulse Engineering, Inc. All rights reserved. All brand names and trademarks are properties of their respective holders.

Cautionary Note: This message contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Actual results may differ materially. This release should be read in conjunction with the factors set forth in Technitrol's report on Form 10-K for the year ended December 31, 2004 in Item 1 under the caption "Factors That May Affect Our Future Results (Cautionary Statements for Purposes of the "Safe Harbor" Provisions of the Private Securities Litigation Reform Act of 1995)."

Note to Editors: DrumCore_hires.jpg photo available at www.pulseeng.com/News/media_gallery.cfm.