EMI filters and Application-Specific Integrated Products (ASIP)

emi filter esd protection

An electromagnetic interference (EMI) filter is used in electronic circuits to improve system immunity against unwanted external electromagnetic signals from neighboring circuits and to avoid emitting radiation (“noise”) that may disturb the same nearby circuits by canceling unwanted frequencies.

EMI noise can adversely affect useful data line signals, possibly altering their functionality, either by coupling (capacitive or magnetic), conduction (common or differential mode), or electromagnetic field coupling (antenna effect).

ST’s EMI filters help electronic designers reduce their design time and achieve required performance levels.

emi filter esd protection

Main applications for EMI filters and ASIP technology

For EMI filters:

Memory card for EMI filters
memory cards
Microphones for EMI filters
Speakers for EMI filters
Parallel displays for EMI filters
parallel displays
Keypads for EMI filters

For ASIP technology:

HDMI for ASIP technology
HDMI 2.0,
HDMI 2.1,
CSI communications
Display Port 2.0 for ASIP technology
DisplayPort 2.0
USB for ASIP technology
USB 3.2,
USB 4.0
SD-Card for ASIP technology
SD-Card 4.2

EMI filter and ASIP product types

Our EMI filter and ASIP portfolio includes 4 main types of solutions designed to reduce high-frequency electromagnetic noise present on power and signal lines. These flexible and highly integrated solutions help electronic engineers meet their main design challenges, while reducing development time and costs.

EMI Filters design
For low-speed digital interfaces or analog application, ST provides EMI filters with integrated ESD protection, targeted to protect lines of memory cards, microphones, speakers, parallel displays, and keypads.
ECMF design
For high-speed data lines such as HDMI 2.0, HDMI 2.1, USB3.2, USB4.0, Display Port 2.0, SD-Card 4.2, MIPI DSI or CSI communications, ST’s Common Mode Filters with integrated ESD protection (ECMF) are tailored to reject a wide range of frequency bands (5G, LTE, 2.4 GHz Bluetooth, and 2.4 and 5 GHz Wi-Fi, to name a few.
ASIP design
For specific applications requiring more integration for space-saving and improved performance, ST has developed integrated circuits using its Application Specific Integrated Product (ASIP) technology. It combines ESD protection at system level (IEC 61000-4-2) with discretes (R, L, C) and over voltage, over current protections, and other IPs such as low-drop-out regulators, deglitch filters and signal conditioning such as multiplexers and level translators among others. ST’s ASIPs reduce system size, complexity, and cost while improving the Failures In Time (FIT) rate for increased longevity.
Automotive applications
ST’s EMI filters, ECMF and ASIPs for automotive applications are qualified as per AEC-Q101 and are compliant with IEC 61000-4-2 and ISO 10605. They are useful in SerDes applications including FPD-link, GMSL, and MIPI DSI or CSI to avoid radiation in vehicle to everything (V2X) (5.9 GHz) and global navigation satellite system (GPS, Glonass, BeiDou, Galileo, and IRNSS) frequencies.

Benefits of ST’s EMI filters and ASIP technology

ST’s EMI filters and ECMF provide a monolithic integration of the required ESD protection at system-level (according to standard IEC 61000-4-2 level 4 +8kV contact) along with a filter that reduces EMI noise on digital or analog communication lines for space-saving purposes.

Main benefits:

  • Requires less PCB space compared to equivalent discrete solutions
  • Increases application robustness against electrostatic discharges and EMI / common-mode noise.
  • Offers a wider frequency range rejection thanks to a lower parasitic inductance compared with discrete solutions.
  • Improved design flexibility as the filter’s resonant frequency is not modified when designers need to slightly change the PCB layout (unlike with discrete solutions).
  • EMI filters are available in first order (R-C) or second order (L-C)