EMI/EMC Filters

With decades of experience in the design and manufacture of Power Supplies, Astrodyne TDI has been researching, refining, developing, and providing EMI/EMC filters for Commercial, Industrial, Medical, and Military applications for more than 60 years. In that time, we’ve earned our reputation as an industry leader that helps companies succeed and operate within applicable electronic and energy standards.


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High-Quality EMI Filter Solutions

For 60 years, Astrodyne TDI has been providing the highest quality EMI filters. To learn more or request a quote now please contact us.  We’re in business to help your equipment — and your brand — be recognized for its power and reliability.

EMI/EMC Filters

EMI/EMC Filter Applications

Medical Applications for EMI Filters

Medical Grade EMI Filters

Our complete line of off-the-shelf filters is available in a medical-grade version. All filters are approved with a variable line to ground capacitances to meet leakage current requirements of all applications and environments. Applications include patient medical devices, diagnostic equipment, surgical beds, MRI and X-ray machines, and more.

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Consumer Applications EMI Filters

Consumer Appliance Filters

Astrodyne manufactures standard and customized custom filters for applications as diverse as portable power tools, vacuum cleaners, appliances and other power supplies …

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Military Applciations EMI Filters

Military EMI Filters - COTS

Most MIL-COTS EMI filters’ ambient rating -40°C to +70°C (-40°F to +158°F) and operate in this range without any de-rating.

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Telecommunications EMI Filters

Telecom EMI Filters

Our extensive offering of telecom filters includes AC and DC EMI power line filters, and custom telecom EMI filters for …

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Custom Military EMI Filter

Custom Military Filters

Astrodyne will address virtually any requirement for a custom EMI Filter. Our years of experience in providing EMI and RFI …

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Custom Commercial EMI Filter

Custom Commercial Filters

Astrodyne designs cost-effective EMI filters and RFI filter solutions for project-specific applications for military, aerospace, commercial …

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Harmonic Filters - PFC Coils - Line Reactors (2)

Harmonic Filters - PFC Coils - Line Reactors

Harmonic/EMI power line filters. PFC Coils and Line Reactors address Power Line Harmonics and Power Quality issues associated with the high-frequency switching designs.

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Why Use an EMI/RFI Filter?

In the broadest terms, EMI and RFI amount to interferences of an electrical or magnetic nature that can degrade how well a piece of electronic equipment performs or the quality of the signal it receives — which is responsible for its nickname “noise.”

From narrowband man-made EMI, such as the hum often heard from power lines, to natural broadband interference like solar flares and lightning strikes, our world is filled with electromagnetic interferences that can range from random and sporadic to continuous and constant.

In addition to external forms of EMI, there are a number of ways electronic devices can produce their own EMI through activities such as generating impedance, or an opposition to the current flowing through a given device. Besides the electronic noise present on signal and power lines, a good deal of high-frequency noise is produced by devices such as electronic appliances, controls, motors, inverters, power supplies and microprocessors.

Sensitive devices, such as computers, medical equipment and military equipment, need to function free of interference for purposes that are often of a mission-critical nature.

Off-the-Shelf Versus Custom EMI Filters

Depending on your product and business sector, you might need a cost-effective off-the-shelf EMI Filter for an application you manufacture. In regards to advanced Aerospace, Military and Medical devices, there might not be a substitute for the performance and ruggedness of a custom EMI filter.

Fortunately, at Astrodyne TDI, our wide selection of quality off-the-shelf EMI filters plus our in-house engineering and design expertise mean that we can always supply you with an EMI solution that seamlessly fits your equipment’s requirements as well as the industry standards. Our EMI Filter solutions range from a collection of small Single Phase components up to Industrial Grade 2,500A/690V Three-Phase Filters. Additionally, the majority of our standard inventory carries International Agency Approvals from recognized organizations such as Underwriters Laboratories (UL), Canadian Standards Association (CSA) and Conformité Européenne (CE).

Astrodyne TDI offers a broad portfolio of power supplies and EMI Filters which have a long legacy of field demonstrated reliability in a wide array of applications. These power supplies range from 5W to 16.5kW and are core technology building blocks that are utilized as the foundation of larger system solutions up to 500kW. Contact us today to learn more.