Integrated Choke incorporates CM ad DM chokes into one unit.

Press Release Summary:

Within 31 x 24.9 mm footprint, PA4040 integrates common mode (CM) and differential mode (DM) choke into same component. This design, by reducing resistance, also reduces power losses across EMI filter portion of power supply. Along with 1,500 Vrms hi-pot and 3.0 mm creepage and clearance safety distance, choke features direct current resistance from 32–245 mΩ. Applications include any AC/DC or DC/AC power supply that uses DM and CM filter and where currents through filter are <3.5 Arms.

Original Press Release:

Pulse Electronics Integrates Common and Differential Mode Chokes into One Component

Reduces footprint by 40% and increases efficiency 30%

San Diego, Calif. -- Pulse Electronics Corporation (NYSE: PULS), a leading provider of electronic components, announces its new series of chokes which integrate a common mode (CM) and differential mode (DM) choke into the same component. Combining two separate magnetic components into a single integrated component reduces power losses across the EMI filter portion of the power supply because it reduces the resistance. It also allows for a reduction in the overall space needed for the choke.

Pulse Electronics' new PA4040 integrated choke has a small 31x24.9mm footprint, making this single CMDM component over 40% smaller than the combined footprint of equivalent CM and DM components. The low direct current resistance, between 32 and 245 mOhms, increases efficiency by 30%. Placing one component, instead of two, saves manufacturing time, costs, and increases throughput.

The PA4040 integrated choke has 1500Vrms hi-pot and 3.0mm of creepage and clearance safety distance so it suits a wide range of safety agency (UL/CSA/VDE) requirements. It can be used in any AC/DC or DC/AC power supply that uses both a DM and CM filter and where the currents through the filter are less than 3.5Arms. Applications include LED lighting drives, solar micro-inverters, motor drives and controls, datacom, and computing. It's an extremely cost efficient option as the cost is approximately 20% lower than that of two separate CM and DM components.

"Integrated chokes have been available before, but mainly for custom applications," explained Geoff Wildman, product line manager (Power), Pulse Electronics. "This catalog release allows for a wider range of customers to enjoy the benefits of integrating the CM and DM chokes."

Common Mode Chokes are used to block or divert unwanted common mode noise in a power supply. Common mode is noise that is common to both the line and neutral in a power supply and essentially circulates through line/neutral and then returns through earth ground by way of parasitic elements in the power supply. Differential Mode Chokes block or divert unwanted differential mode noise in a power supply. Differential mode is noise that circulates through the line and returns through the neutral. Pulse Electronics' component combines these two functions into a single integrated CMDM choke.

"For power supply EMI filter designers looking to increase power density, improve efficiency, and reduce overall cost, the PA4040 series of integrated common mode and differential mode chokes is an exciting development," said John Gallagher, staff field applications engineer, Power Division, Pulse Electronics.

More information can be found on the data sheet located at, the Pulse Electronics website at, or contact us at

About Pulse Electronics:

Pulse Electronics is the electronic components partner that helps customers build the next great product by providing the needed technical solutions. Pulse Electronics has a long operating history of innovation in magnetics, antennas, and connectors, as well as the ability to ramp quickly into high-quality, high-volume production. The Company serves the wireless and wireline communications, power management, military/aerospace, and automotive industries. Pulse Electronics is a participating member of the IEEE, SFF, OIF, HDBaseT Alliance, CommNexus, NFC Forum, MoCA, and IWPC. Visit the Pulse Electronics website at

Copyright ©2014 Pulse Electronics Corporation. All rights reserved. All brand names and trademarks are properties of their respective holders.

Pulse Electronics

Geoff Wildman

Product Line Manager (Power)

Phone: +1 858-674-8356

A R Marketing Inc. (agency)

Andrea Roberts

Tel: +1 858-204-9584 mobile


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