Products for Just About All Occasions

The proliferation of consumer electronic gadgets crammed into ever-smaller packages operating at frequencies well into the gigahertz range has been a boon for new product development in the EMC industry. Manufacturers are introducing a host of products specifically targeted at taming unwanted EMI, especially at high frequencies.

One tried and true shielding solution that has been around for years is gaskets. Available in a variety of sizes, shapes, and materials, gaskets are found in just about every electronic product in the stores today.

One new flexible ferrite material from API Delevan suppresses EMI in the 80-MHz to 3-GHz range and can be provided with an adhesive backing for ease of installation. Tiny EMI GaskettesTM from JEIMC Shielding Technology are used in many hand-held electronics such as cell phones and PDAs. These layered nickel-over-silver conductive gaskets also come with an adhesive backing. Populated with raised dimples to improve conductivity between mating surfaces, the DiamondBack Gasket from Tech-Etch has up to 20-dB attenuation above 2.45 GHz.

Not to be overlooked are the test instruments needed to meet the high-frequency testing requirements of the new EMC standards. “In my view,” noted Thomas Mullineaux, director of sales and marketing at OPHIRRF, “the technological trend driving the EMC industry today is the need to do RF immunity testing to 2.5 GHz from the previous limit of 1 GHz.” There are simulators for immunity testing, horn antennas, enclosures, transient testers, amplifiers, and receivers—the list of instruments specifically targeted at EMC testing applications continues to grow.

Test-equipment manufactures are not providing just instruments, but also complete test solutions. One example is the CWS500D EM Test Simulator from Amplifier Research. This immunity tester includes a signal generator, a directional coupler, a power amplifier, a controller, and software. It performs tests to the specifications of a number of standards.

To keep you informed on products on the market to help you deal with your EMC control and testing problems, EE presents a number of them, including pertinent specifications, in this showcase.

EMC Products

Power EMC/RFI Filters

The BN Series of 480-VAC three-phase filters comprises eight models with current ratings from 7 A to 130 A that offer high attenuation from 150 kHz to 30 MHz and leakage current <3 mA. Based on a book-style design, the filters are narrow and have a small footprint that simplifies panel layout. Features include vented aluminum enclosures, strip or safety terminal blocks, a -25°C to +100°C temperature range, an IP20 protection rating, and compliance with UL 1283, CSA 22.2 No. 8-1986, and EN 133200.

Arcotronics,
www.rsleads.com/303ee-224

Magnetic Active Compensation System

The Magnetic Active Compensation System (MACS), originally designed to shield MRI systems from environmental AC/DC magnetic interferences, now helps achieve image quality in other high field magnetic applications. It protects actively shielded systems from fluctuations in environmental magnetic fields caused by moving vehicles, trains, elevators, and electrical transformers. The MACS surrounds a room with a system of Helmholtz coils monitored by a sensing magnetometer. Reductions of 60 mg to <1 mg are typical.

ETS-Lindgren™, an ESCO Technologies Co., www.rsleads.com/303ee-235

Multicavity Shield

snapSHOTTM EMI Shield is a custom-designed, multicavity EMI shielding product that attaches to a PCB using the company’s snap-attachment system. It is made from metallized, high-temperature plastic and can be provided in bulk, trays, or tape-and-reel. The shield attaches to the PCB by snapping it into place on special BGA spheres that have been reflowed on the board. The shield removes easily from the spheres by hand without special tools.

W. L. Gore & Associates,
www.rsleads.com/303ee-245

EMC Simulator

The EM Test Model CWS500D Simulator for RF conducted immunity testing comprises a signal generator; a directional coupler; a 100-W, 10-kHz to 400-MHz power amplifier; a controller; and software. It currently performs testing to many automotive and telecom standards including ISO 11452-3, -4, -5; SAE J1113-4; and GM3097/3100. Output power is 75 W minimum, and harmonic distortion is <15 dBc at maximum power. The CWS500D features an IEEE 488.2 interface that accommodates an external dual-channel power meter for measuring forward power and monitoring injected RF current.

Amplifier Research,
www.rsleads.com/303ee-222

Ferrite Material

Series FFAM, an RF absorbent flexible ferrite material, provides EMI suppression in the 80-MHz to 3-GHz frequency range with electrical resistance from 106 to 108 W. The material is available in sheet form in four sizes from 100 × 100 mm to 400 × 400 mm and six thicknesses from 0.25 mm to 2.5 mm. It can be die cut into gaskets and produced with nonconductive adhesive backing.

API Delevan,
www.rsleads.com/303ee-223

Transient Voltage Suppressors

The USB Series of miniature surface-mount transient voltage suppressors provides bidirectional ESD protection and EMI attenuation for computer I/O, USB, and infrared ports and RF links. The suppressors are available in three sizes: 0603 standard, 0405 two-capacitor array, and 0612 four-capacitor array. The series has a typical capacitance of 22 pf at 1 MHz, an operating temperature range from -55°C to +125°C, and an energy rating of 0.015 J.

AVX,
www.rsleads.com/303ee-225

Active Horn Antenna

Designed for EMC emissions testing in the 1- to 18-GHz range, the linearly polarized Model AHA-118 Horn Antenna has a built-in preamplifier with an average gain of 20 dB. The integrated preamplifier helps reduce low-level signal losses associated with typical emissions test setups. The AHA-118, is powered by an external DC adapter and constructed of lightweight aluminum with a corrosion-resistant conductive coating.

Com-Power,
www.rsleads.com/303ee-228

Spectrum Analyzer

The Model 401B Personal Spectrum Analyzer has a frequency range of 1 MHz to 1.024 GHz, 3-dB resolution bandwidths of 120 kHz and 1 MHz, and an amplitude measurement range of -25 dBm to -95 dBm. The 1.2-lb 401B can make precompliance measurements with displayed limit lines to FCC Part 15 A/B, CISPR 11 A/B, and CISPR 22 A/B. All measurement functions are programmable through an RS-232 interface. Accessories include calibrated E-Field and H-Field probes, a broadband active antenna, and a preamplifier.

Bantam Instruments,
www.rsleads.com/303ee-226

Small, Thin Gaskets

Ultra-thin and narrow EMI GaskettesTM provide shielding to very narrow spaces and openings typically found in notebook computers, cellular phones, PDAs, and other hand-held or small electronic devices. The flexible gaskets are X-Y-Z conductive and made of layers of nickel-over-silver-coated materials with a peel-and-stick adhesive backing. They come in a wide variety of sizes and shapes including custom configurations.

JEMIC Shielding Technology,
www.rsleads.com/303ee-234

Multilayer Chip Inductors

A line of multilayer surface-mount (SM) chip inductors features a full monolithic structure with silk-screened windings on either a ferrite or ceramic body. The ferrite body inductors form a closed magnetic circuit and are self-shielding, which allows for dense spacing on circuit boards. They can be used at frequencies into the hundreds of megahertz depending on the inductance value. The ceramic body inductors also are self-shielding and can be used in a frequency band from hundreds of megahertz into the gigahertz region.

Fair-Rite Products,
www.rsleads.com/303ee-231

Modular Shielded Boxes

A modular system consisting of conductive strips shields parts on PCBs. One strip can be configured into a range of boxes with dimensions changing in ¼” increments. The strips come in widths of 4, 8, 12, 16, and 20 mm and thicknesses of 0.12 mm to 0.5 mm. Custom sizes also are available. The system mounts on a PCB via pressure-sensitive self-adhesive or solder pins.

Holland Shielding Systems BV,
www.rsleads.com/303ee-236

Immunity Test System

The CIT-10 Automated Test System from Franconia performs testing of immunity to conducted disturbances per EN 61000-4-6/IEC 1000-4-6. An integrated function generator outputs 0% to 100% amplitude-modulated signals or pulse-modulated signals with duty cycles of 10% to 90% over the frequency range of 1 Hz to 100 kHz. Calibration of all coupling/decoupling devices is performed automatically.

Credence Technologies,
www.rsleads.com/303ee-229

High-Shielding Enclosures

Heavy-duty enclosures continue to provide 80 dB of attenuation from 200 MHz to 1 GHz and 60 dB from 1 GHz to 10 GHz after completing NEBS Zone 4 earthquake simulation. The enclosures, featuring high EMI/RFI resistance, include I/O areas for cable and power, fans, and EMI air filtering.

Equipto Electronics,
www.rsleads.com/303ee-230

Empirical Test Fixture

The Empirical RFI Suppression Test Fixture, a ferrite core encased in a heavy-duty hinged nylon plastic enclosure, determines if a ferrite suppressor is feasible in a given situation. When this insertion-loss material is applied to a circuit, a rough estimate of the attenuation effect can be previewed. Developed for R&D and test, the 2” OD/1” ID fixture clamps over any data cable. Three standard material formulas are available: #28 for frequencies from 10 MHz to 1 GHz, #33 for 1 MHz to 30 MHZ, and #25 for peak suppression of interference occurring at 500 MHz to 700 MHz.

FerriShield,
www.rsleads.com/303ee-232

Transient Tester

The TRA2000IN6 covers the transient immunity test needs of the world market, such as IEC/EN 61000-4-X Series and ANSI/IEEE C62.41/C62.45. It features EFT, ESD, surge, ring wave, dips, interruption, V-variation, telecommunications surge, AC, and impulse magnetic field test. Current and voltage peak measurements are part of the standard tester, which allows automatic test and automatic reporting of the test results. Remote control is via an RS-232 optical link. Special power-line coupling for the United States and Canada is included.

HV Technologies,
www.rsleads.com/303ee-233

Power Supplies

The MX Series of programmable power supplies provides single-phase or three-phase AC outputs, line to neutral, of 0 to 150 VAC, 0 to 300 VAC, and 0 to 400 VAC, or one to three DC outputs. Output power in the series is 45 kVA for one unit with the capability of combining up to three units for a maximum output power of 135 kVA. The programmable output frequency ranges from 16 Hz to 800 Hz. The supplies can be operated via a front-panel keyboard with a menu-driven interface or remotely over an RS-232 or IEEE 488 interface.

California Instruments,
www.rsleads.com/303ee-227

Power Amplifier Module

The Model 5143 is a 50-W microwave amplifier that functions over the 0.7 to 3.0 GHz frequency range and sports a minimum small-signal gain of +48 dB. Powered by nominal line voltages, the unit operates up to 120°F. IEEE 488 and RS-232 interfaces are optional. It is suitable for testing to the emerging RF immunity standards.

OPHIRRF,
www.rsleads.com/303ee-240

Microwave Amplifier

The Series 2000 Linear Broadband Microwave Amplifiers deliver up to 700 W over the 0.8- to 2.2-GHz frequency band. The series includes 1-, 7-, 27-, 55-, 100-, 150-, and 200-W amplifiers in 3U-size modules, a 360-W unit in a 6U format, and a 700-W unit in a 15U format. Gain variation with frequency is ±2 dB, and harmonics and spurious are -20 dBc and -70 dBc, respectively. Color LED bar graphs on the front panel provide an indication of incident and reflected power.

Milmega,
www.rsleads.com/303ee-239

Shielding Assortment

The EMI Shielding Kit contains rolls of laminate materials, die-cut sample parts, and product literature in a carrying case. The laminates include EM2710: 0.002” copper on 0.010” Lexan FR700 with a UL 94-VO rating; EM1410: 0.002” aluminum on 0.010” PVC with a UL 94-V1 rating; 0.002” aluminum on 0.005” Mylar EL; and 0.002” aluminum with conductive adhesive.

Orion Industries,
www.rsleads.com/303ee-241

Instrument Control Software

EMC Total Integrated Laboratory Environment (TILE) Version 3.1 Software is a general instrument control system with links to word processing, database, and spreadsheet software. The main program provides a graphical, flowchart-oriented method of designing and executing EMC tests. Unique routines control the various instruments used to perform each test. TILE supports a number of instruments, and Version 3.1 now accommodates all EMC receivers currently on the market. Also new are extensive failure-analysis subroutines providing efficient evaluation of the unit under test.

Quantum Change,
www.rsleads.com/303ee-242

EMI Receiver

The SMR4518 EMI Receiver has a frequency range of 8 kHz to 18 GHz and a measurement accuracy of <1.5 dB for 9 kHz to 1.005 GHz, <2.0 dB for 1.005+ to 2.75 GHZ , and <2.5 dB for 2.75+ to 18 GHz. It provides resolution of 100 Hz, a frequency accuracy of 10-6 , and an operating temperature range of -20°C to 60°C. Various functions can be stored in the unit including device presetting, measured data, frequency spectrum, limit lines, and transducer correction factors. The SMR4518 measures signals from -26 to 137 dBµV.

Schaffner EMC,
www.rsleads.com/303ee-243

High-Frequency Shielding

DiamondBack EMI/RFI Shielding features a textured contact surface that increases attenuation at 2.45 GHz and above. Hundreds of raised dimples in the contact area enhance the conductivity between the gasket and the mating surface. Nonabrasive DiamondBack texturing can be applied to most standard profiles to achieve up to a 20-dB attenuation improvement at high frequencies without raising the compression force. The gasketing is available with several mounting and finish options, has no compression set, and offers longevity over plated fabrics.

Tech-Etch,
www.rsleads.com/303ee-244

Conductive Epoxy

EP51N is a nickel-filled, two-component epoxy that sets up in 5 to 10 min and adheres to a variety of substrates. It fully cures in 8 to 12 h at room temperature or in 30 min at 200°F. The service temperature range of EP51N is -60°F to +250°F.

Master Bond,
www.rsleads.com/303ee-238

Shielded Cans

Designed to provide shielding for board-level components, Drawn Cans feature seamless corners for near- and far-field attenuation at high frequencies. Customer-specified configurations include ventilation holes and formed partitions for multicompartment shielding requirements. The cans come in plated cold-rolled steel, brass, stainless steel, and nickel silver in heights up to 0.25” and lengths and widths from 0.30” to 2.0”. The EZ Peel scored lids are removable and resealable.

Laird Technologies,
www.rsleads.com/303ee-246

Clock Oscillator

The EMC530 Clock Oscillator is a spectrum spread modulator that reduces electromagnetic emissions and associated harmonics of the clock frequency by as much as 20 dB when compared to standard oscillators. It is a direct replacement for crystal oscillators and compatible with standard 14-pin DIPs. Selectable clock frequencies are 11 MHz to 120 MHz.

MEDCONX,
www.rsleads.com/303ee-237

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Published by EE-Evaluation Engineering
All contents © 2003 Nelson Publishing Inc.
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without the express written consent of the publisher.

March 2003