Thyristors

Thyristors are high-power semiconductor devices used for switching and rectification in AC and DC systems. They include Silicon Controlled Rectifiers (SCRs), Triodes for Alternating Current (TRIACs) for bidirectional control, and integrated power modules designed for demanding load conditions. With their ability to handle high currents and voltages, thyristors are widely used in motor drives, power supplies, and industrial control systems.

Online Components stocks hundreds of thyristor part numbers from authorized suppliers like NTE Electronics and Sensata/Crydom. With U.S.-based inventory, low minimums, and fast global shipping, you can secure the devices you need to keep your systems powered and production running.

How to Choose the Right Thyristor

Type

SCRs provide unidirectional current control and are ideal for rectification and DC switching. TRIACs handle bidirectional current, making them common in AC switching. Thyristor modules combine multiple devices for high-power industrial systems.

Electrical Ratings

Check maximum current load, voltage blocking capability, and gate trigger current. Select parts with a safety margin above system demands to improve reliability.

Package & Mounting

Through-hole devices are commonly used in lower-power applications, while panel-mount and module packages are better suited for high-current loads and industrial enclosures.

Popular Applications for Thyristors

• Motor Control & Drives — SCRs and TRIACs regulate motor startup, speed, and braking.
• Power Supplies — Used in rectification and voltage regulation for both consumer and industrial power systems.
• Lighting & HVAC — TRIACs enable smooth dimming and load control in AC mains equipment.
• Industrial & Energy Systems — Thyristor modules protect and manage high-power distribution, renewable energy arrays, and UPS systems.
• Appliances & Consumer Electronics — Compact TRIACs provide reliable AC control in washers, dryers, and small appliances.

Why Buy Thyristors from Online Components?

• Authorized Distributor Since 1999: Genuine, traceable supply from trusted manufacturers.
• Extensive Selection: SCRs, TRIACs, and power modules in stock for immediate delivery.
• Fast Fulfillment: Same-day U.S. shipping and predictable flat-rate global options.
• Competitive Pricing: Transparent screen pricing with low MOQs for both prototypes and production runs.
• Easy Ordering: Advanced search and parametric filters make sourcing straightforward.

Thyristors: What You Should Know

What’s the difference between SCRs and TRIACs?

SCRs conduct current in one direction, making them well-suited for use in rectifiers and DC switching applications. TRIACs conduct current in both directions, which is why they are widely used in AC dimming and motor control applications.

How do I size a thyristor for my application?

Always select a device with current and voltage ratings that exceed the expected operating levels. Check gate trigger current and ensure thermal management matches system load.

When should I use a thyristor module instead of discrete devices?

Modules are ideal when high currents or voltages exceed the capabilities of discrete devices. They integrate multiple thyristors in a panel-mount form factor, simplifying installation and improving reliability.

Are thyristors suitable for high-frequency switching?

Thyristors excel in power control but are limited in very high-frequency switching. For fast switching applications, MOSFETs or IGBTs may be more suitable.

How do thyristors contribute to system reliability?

By providing stable, repeatable switching in high-load environments, thyristors reduce wear on mechanical relays and extend the lifetime of power systems.