High-temperature Triacs

Designed for high-temperature switching control and improved performance, our T-series Triacs and 6H/8H Triacs are ideal for 4 to 50 A applications rated at 600 V or 800 V. 


  • 800 V, 150°C 8H high-temperature Triacs

    Designed for thermal-intensive heavy-duty applications, ST's 8H Triacs are high-voltage (800 V) switches with full power line capability and immunity for driving tough loads in increasingly compact modules thanks to their no-compromise rating at temperatures up to 150°C.

    From 230 V single-phase to 400 V three-phase supplies, ST's 8H Triacs are designed for use as an AC mains switch for water heaters, industrial automation, HVAC, roller shutters and building lighting control units. With snubberless™ voltage transient immunity, these triacs are well adapted to handle the EMI disturbance and unstable mains environments typical of these AC network connected applications.

    Thanks to its low and stable leakage currents and transient current switching capability twice the nominal current, the 8 to 30 A range of the 8H Triacs ensures excellent switching capabilities. Available in a ceramic-insulated TO-220AB package, D2PAK or classical TO-220AB packages, 8H Triacs also let designers reduce the size of heatsinks in their solutions thanks to the maximum 150°C junction temperature (TJ). A silicon semiconductor and solid-state solution, this series offers certain advantages over traditional relays including its sparkless and non-aging switch characteristics.

  • 600 V, 150°C 6H high-temperature Triacs

    With high inrush and transient current capability, ST's 6H high-temperature (600 V) Triacs are designed for AC power equipment including motors, high-end home appliances, heating units, coffee machines and food processors.

    The 10 to 50 mA gate current versions make it easier to drive with an MCU port, while still ensuring voltage transient immunity at a standardized 6 kV IEC61000-4-4 level.

    Able to control transient currents up to 4 times its nominal IT(RMS), designers can use smaller silicon triacs for the same job, a particularly valuable feature on inductive loads. Or you can reduce the heatsink size using the enhanced 150°C junction temperature (TJ) for higher thermal headroom for smaller, more robust appliances.

  • T-series high-temperature (800 V) Triacs

    Targeting applications with high EMI constraints, ST’s T-series high-temperature Triacs are designed for the ever-increasing number of AC loads in appliance control. These AC appliance switches meet both the immunity and high-commutation needs, offering a cost-effective solution for power control.

    For this series, both immunity (dV/dt) and commutation capability (dI/dt) are specified, as well as the low gate current. This last parameter is key, as it helps optimize the power supply and allows direct drive capability through a single resistance between the microcontroller and the triac, for all 10 mA gate current types.

    6 to 25 A 800 V T-series Triacs with 35 mA gate types and 800 V capability are now available in a D2PAK package, providing improved EMC immunity and commutation for a wider range of loads.

    The trade-off of surge current (ITSM) versus immunity and commutation capability is improved. This is one step ahead of the usual offer, and a unique range in the market.

Designers can now use our online Triac / AC switch simulator to find out more about design characteristics and select the best device for your application.

High-temperature triacs belong to our STPOWER family.


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