Subelement C: Components— Topic 23: SCRs, Triacs
Question 3-23C5
Element 3 (GROL)What are the three terminals of a TRIAC?
Explanation
A TRIAC is a three-terminal semiconductor device that functions as a bidirectional AC switch. Its three terminals are the Gate, Anode 1 (A1 or Main Terminal 1, MT1), and Anode 2 (A2 or Main Terminal 2, MT2).
The Gate terminal controls when the TRIAC turns on, typically by applying a small current pulse. Once triggered, current can flow in either direction between Anode 1 and Anode 2, allowing the TRIAC to switch AC power.
Options A (Emitter, base 1, and base 2) describes a Unijunction Transistor (UJT). Option B (Base, emitter, and collector) describes a Bipolar Junction Transistor (BJT). Option C (Gate, source, and sink) is incorrect; while "gate" and "source" are FET terminals, "sink" is not a standard terminal name (it should be "drain").
Related Questions
3-23C3 Which of the following devices acts as two SCRs connected back to back, but facing in opposite directions and sharing a common gate?3-23C4 What is the transistor called that is fabricated as two complementary SCRs in parallel with a common gate terminal?3-23C6 What circuit might contain a SCR?3-24C1 What is one common use for PIN diodes?3-24C2 What is a common use of a hot-carrier diode?