CATEGORIES

Thyristors (SCR) and AC switches

Designed for high immunity against glitches on mains and high load supplies, the Thyristors, also known as silicon-controlled rectifiers (SCR), triacs and logic-level gate ACS circuits are switches working on 120, 240 and 480 V AC power lines for appliances, tools, converters and drive systems. Thyristors (SCR) and AC Switches belong to our STPOWER family.

ThyristorsThe most energy efficient, simplest gate drive, Thyristors, are also the toughest 200 to 1400 V bidirectional switch for controlling alternating current mains power.

With a current range from 0.2 to 80 A, Thyristors are used in home and office appliances, as well as industrial automation. More concretely, AC switch circuits are included in compressor drives, water heater, power tools, static relays, roller shutters, motorbike regulators and more recently, circuit breakers and electrical vehicle chargers.

Smart-building connected objects powered by AC mains is the latest innovation where Thyristors are contributing to climate and energy controls.

To meet the wide variety of assembly automation requirements, ST's portfolio offers a full range of surface-mount SMD packages from the tiniest 0.8 A SMB Flat ACS to the power-carrier 80 A D3PAK SCRs. Our through-hole packages include the thermally excellent 2500 V ceramic-insulated TO-220 and the new full resin-molded TO-220 package.

Explore our large choice of packages for our thyristors (SCR), Triacs and ACS switches.

Quickly find the thyristor or AC switch that best fits your design by simply entering the main I/O and gate parameters in our AC Switch Simulator.

Triacs

TRIAC

Today’s triacs are perfected with low gate current drive, high immunity and commutation at temperature (see our T series and H series).

AC Switches

AC Switches

Our ACS™ AC switches ensure the interface between a gate and an MCU with an integrated over-voltage protection (OVP) function.

SCRs

SCRs

Silicon-controlled rectifiers (SCR) are the most immune switch to voltage spikes and their load commutation capability is very high.

ASD

Application-Specific Discretes

ASDs (Application-Specific Discretes) are a collection of gas and fuel ignitors integrating SCR building blocks.

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More from Thyristors (SCR) and AC switches portfolio

eDesignSuite

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
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Solar Battery Charger

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Displays interactive and annotated schematic
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Provides a step-by-step optimized design of power section and control loop
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AC Switches Simulator

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Rectifier Diodes Simulator

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Active Filters

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Provides current error graphs

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Provides current error graphs.
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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