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Johanson Technology Launches New EF Series Multi-Function EMI Filters

Oct. 21, 2026

Multi function EMI filters. One Filter. Multiple EMI problems solved.

One Filter. Multiple EMI Problems Solved.

Common-mode noise. Differential-mode noise. One compact filter solution.

Johanson Technology is launching the new EF Series Multi-Function EMI Filters, giving design engineers a more integrated way to suppress unwanted electromagnetic energy while reducing the complexity of traditional discrete filter networks.

EMI problems can quickly turn into extra components, lost PCB space, additional routing, board re-spins, and more time spent troubleshooting compliance.

The EF Series is designed to address both common-mode and differential-mode EMI without breaking the DC or signal path, allowing a single component platform to support power, signal, and balanced-pair applications.

Instead of selecting a filter based only on nominal capacitance, engineers can use frequency-characterized attenuation data to evaluate EF Series candidates against the actual frequencies creating problems in their design.

Designed to Simplify EMI Mitigation

  • Common-mode and differential-mode suppression
  • Ultra-low ESL for effective high-frequency filtering
  • Straight-through signal or DC path with no series-winding voltage drop
  • No series-winding current-rating constraint
  • EIA case sizes from 0402 through 1812
  • Frequency-characterized responses for targeted filter selection
  • Potential to reduce discrete component count, PCB area, routing complexity, and vias

Built for Noise-Sensitive Electronic Systems

The EF Series can support EMI mitigation in:

  • Power supplies and DC-DC converters
  • Industrial automation
  • Automotive and EV electronics
  • High-speed digital and RF systems
  • Aerospace and defense electronics
  • Medical electronics
  • Wireless charging
  • Motors and motor-control systems
  • Other noise-sensitive designs

More Than a Component Supplier

EMI behavior depends on the complete system—including PCB layout, grounding, cables, operating modes, and coupling paths.

Johanson Technology’s engineering team can help with:

  • Filter selection
  • Schematic review
  • PCB layout recommendations
  • EMI troubleshooting
  • Compliance optimization

Our goal is simple: Help engineers spend less time fighting noise and more time finishing the design.

Simplify the Filter. Save the Space. Solve the EMI.

Use the EF Series to suppress common- and differential-mode noise with one compact, ultra-low-ESL solution—reducing filter complexity while preserving valuable PCB space.

Request EF Series samples and evaluate the solution in your board, or contact Johanson Engineers for technical support.

To learn more, visit Multi-Function EMI Filters for Common & Differential Mode Noise Suppression | Johanson Technology

Planning your PCB Layout?

See how proactive filter placement and layout decisions can help improve EMI performance before compliance testing.

Check out the technical white paper at Proactive EMI Filter PCB Layout and EMC Workflow