Triacs

A triac is a three-terminal electronic component that functions as a switch or a gate in an AC (alternating current) circuit. It can be used to control the flow of current in a circuit by turning it on or off in response to a control signal.

A triac consists of two thyristors connected in inverse parallel, with the gate of each thyristor connected to the other thyristor’s cathode. When the control signal is applied to the gate of one of the thyristors, it begins to conduct, allowing current to flow through it. This causes the other thyristor to also begin conducting, forming a conduction path between the two main terminals (anode and cathode). The triac can be turned off by removing the control signal or by applying a reverse voltage across the main terminals.

Triacs are often used in AC switching applications, such as dimming light bulbs or controlling the speed of motors. They have the advantage of being able to control AC power without the need for a transformer, which makes them smaller and more efficient than other types of switches.