By what method can a TRIAC be triggered into conduction______________?
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Answer: C. Either (a) or (b)
Explanation
A triac can be triggered into conduction by applying either a positive or a negative voltage pulse at its gate. This dual polarity gate triggering capability allows flexible control circuit design for alternating current applications. The bidirectional semiconductor structure responds to gate current regardless of whether main terminal one is positive or negative. Triacs are bidirectional alternating current switches designed to conduct current in both flow directions through the device. Gate triggering quadrants define the various combinations of main terminal and gate voltages required for reliable turn on. Bidirectional switching simplifies alternating current phase control circuits by eliminating the need for dual polarity matching.
Positive voltage at the gate terminal alone ignores the triac ability to trigger with negative gate pulses as well. Negative voltage at the gate terminal alone fails to account for successful triggering using positive polarity pulses. None of these is incorrect because option C accurately states that either positive or negative gate voltages can trigger the triac.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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