July Tech Focus: EMI Suppression

Electromagnetic interference (EMI) is a notorious enemy of electronic device design, defined as the electrical or magnetic interference that degrades or damages the integrity of a signal or the components and functionality of electronic equipment. Suppressing EMI is key in electronics design, as many products are built with an EMI filter or other component that combats such interference. Here are some new innovations in this space.

EMI filter for AC voltages up to 277 V

SCHURTER has extended its family of EMI filters for 1-phase systems with its new FMAB HV series. The new filter is suitable for applications requiring AC voltages up to 277 V, such as 1-phase of the 3-phase 480/277 VAC wye system, typically used for lighting applications in North America. It is also rated for 400 VDC. Due to its high symmetrical attenuation, the filter series is particularly suited for devices using semiconductors, which regulate high outputs. Furthermore, the compact, fully enclosed housing provides optimized shielding through a very stable, flush mounting. The FMAB HV offers a current range from 1 A to 20 A at 277 VAC / 277 VDC according to IEC standard, and 277 VAC and 400 VDC according to UL/CSA standard. It has ENEC and cURus approval. Temperature range is from -40 °C to 100 °C. SCHURTER

Built for space, DC-DC converters have integrated EMI filters

VPT, Inc., a HEICO company, released its SGRB Series of space-qualified DC-DC converters at the Satellite 2019 Show. Using advanced GaN technology, the SGRB is capable of very high efficiency—up to 95%— as well as radiation tolerance. A fixed-frequency, reduced voltage switching topology results in very low input and output noise, making it suitable for use in telecommunication systems. Specifically designed for applications facing the harsh radiation environments of space, the SGRB series has been characterized to total ionizing dose of 100 krad(Si), including enhanced low dose rate sensitivity, and single event affects performance to 85 MeV/mg/cm2. The SGRB Series features an integrated EMI filter, 100 V input and 28 V, 400 W output, and is rated for full-power operation from -35°C to 85°C. VPT

EMI pre-compliance analysis option for spectrum analyzers

RIGOL Technologies recently announced a significant addition to its UltraReal family of real-time spectrum analyzers with the release of a new integrated EMI Application Mode for EMI pre-compliance measurements. RIGOL’s EMI Measurement Application provides a complete EMI pre-compliance solution allowing engineers to measure, compare, analyze, and report on EMI issues throughout their design process. The EMI Application Mode allows for easy measurement setup. Features like integrated CISPR bandwidths and detectors, simple limit line construction, automated multisegment scan, and up to three simultaneous detectors make it simple to get initial scans and measurements. Advanced capabilities like real-time detector measurements, automated peak/limit searches, and simple correction table integration make configuring more complex test environments and analyzing results easier. In addition, comprehensive setup, storage, and report-generation capabilities make it easy to document, share, and repeat your tests. RIGOL Technologies

High-current toroidal inductor design kit

Signal Transformer recently announced their new High Current Toroidal Inductor (HCTI) Design Kit. This kit provides a varied selection of toroidal inductors to design engineers who are looking for solutions to support EMI/RFI filtering and energy storage in industrial and consumer goods applications. The HCTI Design Kit features toroidal inductors that have an inductance range of 10-1000uH, a DC resistance range of 0.005 Ω to 0.3 Ω, and a DC-rated current ranging from 2.4A to 20A. Signal Transformer products utilize custom design coil construction and ferrite material to have high efficiency through reduced core loss, low magnetic radiation from self-shielding, and high energy storage with distributed air gaps. Signal Transformer