triac

electronics

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July 14, 2026

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A triac is a bidirectional, three-terminal thyristor used in AC applications. It can switch current in either direction by applying a small current to its gate. Essentially, a triac is made by integrating two thyristors connected in an inverse parallel configuration.1

Thyristors, in general, are semiconductor devices that can switch between a high-resistance "off" state and a low-resistance "on" state. They are used in various applications, from controlling motor speeds in home appliances to power conversion in high-voltage transmission lines. Triacs are commonly employed in devices like light dimmers, motor-speed controls, and temperature controls.12

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semiconductor device
Thyristors
…three-terminal thyristor is called a triac. This device can switch the current in either direction by applying a small current of either polarity between the gate and one of the two main terminals. The triac is fabricated by integrating two thyristors in an inverse parallel connection. It is used in…
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…three-terminal thyristor is called a triac. This device can switch the current in either direction by applying a small current of either polarity between the gate and one of the two main terminals. The triac is fabricated by integrating two thyristors in an inverse parallel connection. It is used in…
Read More