Protections and EMI filters

Integrated circuits are exposed to several possible sources of stress coming from power and or data lines which can result in malfunctions or even lead to dramatic failures. To ensure that these circuits are remain reliable and operate correctly, it is important to include protection mechanisms.
ST's Protection and EMI filter portfolio offers a unique and comprehensive choice of high-performance components to ensure safe electronic system operation and immunity from electromagnetic interference (EMI).


Produced with ST's technologies, they ensure the best protection and filtering performance for demanding systems.

Our solutions are housed in industry standard packages in addition to cost-effective alternatives such as high-power-density packages for transient voltage suppressor (TVS) diodes, ultra-small and multi-line WLCSP devices for ESD and EMI filters.

From 5000 W SMC packages to 01005 and smaller, we help engineers with design simplification, space savings and cost optimization.

Our ASIP technology enables the horizontal integration of passive components into high-reliability silicon circuits and is compatible with the latest vertical integration trends such as SIP (System In Package) systems thanks to ultra-thin packages down to 80 µm.

Automotive-grade qualification for smart mobility applications

Automotive grade qualification (AEC Q101) and Automotive surge compatibility is available for our Automotive line-up that is rapidly expanding to meet the latest EV and Autonomous driving challenges.

All ST production sites adhere to the internationally recognized quality management standards ISO 9001 and IATF (international Automotive Task Force) 16949.

Product types:

EMI Filter logo with waves that flatten
An EMI filter helps electronic circuits work better by blocking unwanted signals from other circuits nearby and preventing them from causing problems. It also stops the circuits from making noise that could disturb other components.
ESD Protection logo
ESD protection is required for EMC Immunity. It ensures that equipment can work properly in its environment by reducing the amount of electromagnetic energy that could cause physical damage.
Thyristor surge suppressor logo
When a TVS is not strong enough to ensure compliance with required standards, a TSS is added to prevent overvoltages or power surges from damaging power supplies.
Transient voltage suppressors with the TVS logo
A TVS is a special type of diode designed to protect circuits against power surges. ST's Transil™ protection devices can handle high current surges for a short time.

FREE WEBINAR EMC - system immunity against electrostatic discharges webinar

During this one-hour webinar, you will learn how to make your electronic system more robust against destructive Electrostatic Discharges (ESD) by using ST ESD Protection components.

During this webinar you will learn about:

  • ESD major root causes and EMC standards
  • ST ESD Protections, which can help to protect your application against ESD
  • Many real application examples demonstrating where protections play an important role
  • How to select the best protection for your use cases

Maximizing MCU performance with advanced protection and EMI filtering

ST's ESD protection and EMI filter devices offer high protection efficiency with low clamping voltage (VCL), low leakage current (IRM) for protection transparency, and ultralow capacitance and ultrawide bandwidth for signal integrity.

Protection and Filter Devices

FREE WEBINAR 10.7 GHz bandwidth common-mode filters for new USB4 and HDMI 2.1 standards

During this one hour webinar, you will learn how to optimize antenna RF sensitivity in noisy conditions in compliance with EMC standards for industrial and personal electronics applications. This webinar will help hardware engineers concerned with antenna de-sense or EMC standards compliance, as well as embedded systems engineers looking for ways to design more compact high-speed USB and HDMI connectors. There is a dedicated session with various RSSI, spectrum analyses, and transmission speed test results for Wi-Fi and 10 Gbps data transmission.

  • Why ECMF is required:
    • Noise suppression and common mode filtering
    • Antenna de-sense and immunity concerns for compliance with EMC standards
  • ST application lab session with:
    • SSI test results, spectrum analysis, and transmission speed test results of 10 Gbps USB transmission
    • Overview of latest USB4 and HDMI 2.1 standards
    • ST ECMF application and product overview

Get the right protection from the very beginning with ST's smart selection tool and electrothermal models

Are you spending countless hours selecting the right protection components for your design? This one-hour webinar shows how you can easily leverage ST’s smart selection tool and electrothermal SPICE models and choose the most appropriate protection, right from the beginning. The best part? Our tools are easy to use and compatible with ST’s latest generation of TVS. These high-performance transient voltage suppressors, with a power rating of up to 5 kW, come in a compact SMC package. They protect hardware components from voltage surges, spikes, and much more.

    Why you should watch
  • Our experts will guide you through real-life lab demos to help you evaluate the benefits of this new generation of TVS devices and our latest tools
  • You’ll learn how to select and simulate the right TVS in record time
  • Discover ST’s latest TVS products for a wide range of applications and markets
  • Learn how to use ST’s design tools and SPICE electrothermal models
  • Explore real-life lab evaluation results
  • Compare our solution with the competition


eDesignSuite is a comprehensive set of easy-to-use design-aid utilities ready to help you streamline the system development process with a wide range of ST products.

Power Management Design Center

Thermal-electrical Simulators for Components

Signal Conditioning Design Tool

NFC/RFID Calculators

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Power Supply Design Tool

SMPS design, by topology, by type and by product
PFC design with analog and digitial control
Supports various PCB configurations
Choose type:
Solar Battery Charger

LED Lighting Design Tool

Handles AC-DC and DC-DC design in common topologies
Displays interactive and annotated schematic
Provides current/voltage graphs, Bode plots, efficiency curves and power-loss data
Choose type:

Digital Power Workbench

Provides a step-by-step optimized design of power section and control loop
Generates the STM32Cube embedded software package for custom applications and allows firmware project generation, compatible with multiple STM32 IDEs

Power Tree Designer

Specify input/output power for each node in the tree
Check for consistency
Design each individual node
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AC Switches Simulator

Select ratings and application waveforms
Get junction temperature and blocking voltage graphs
Search and sort suitable devices

Rectifier Diodes Simulator

Select ratings and application waveforms
Estimate power losses
Search and sort suitable devices


Supports long mission profiles
Provides power loss and temperature graphs
Helps define heatsink thermal properties

Twister Sim

Help select the right ViPOWER Automotive power device
Supports load-compatibility, wiring harness optimization, fault condition impact and diagnostic analysis
Supports various PCB configurations

TVS Simulator

Specify system ratings and surge waveform
Search and sort suitable devices


Build simple schematics and firmware inputs in minutes
Quickly generate reliable estimates of battery life, system power consumption and bill of materials costs
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Active Filters

Handles multi-stage-designs and common topologies
Returns circuit component values
Provides gain, phase and group delay graphs
Low Pass, High Pass and Band Pass


Handles most common configurations
Returns circuit components values
Provides I/O signal waveforms
Inverting, Non Inverting, Window

Low side Current Sensing

Returns circuit component values
Provides current error graphs

High side Current Sensing

Provides current error graphs.
Help to select the right High side current sensing and shunt devices.
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NFC Inductance

Input geometry and substrate properties
Get antenna impedance

UHF Link Budget

Enter forward and reverse link characteristics
The tool returns link budget estimate

NFC Tuning Circuit

Enter antenna parameter and matching target
Select the topology of the matching network
The tool returns component values for the desired design targets