What structural layers make up a TRIAC power semiconductor device____________?
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Answer: A. Two SCR’s connected in reverse parallel
Explanation
Structurally a triode for alternating current consists of two conventional silicon controlled rectifiers connected in reverse parallel. This dual device anti parallel configuration allows bidirectional current conduction through the main semiconductor switch terminals. Connecting two thyristors back to back enables triggering in both positive and negative half cycles of alternating current. A standard silicon controlled rectifier is a unidirectional four layer semiconductor device conducting current in only one direction. Reverse parallel connection means the anode of one thyristor is connected to the cathode of the other device. Monolithic integration places these complementary structures onto a single common semiconductor silicon substrate during manufacturing.
Connecting two silicon controlled rectifiers in standard parallel would only increase unidirectional current capacity rather than enabling AC switching. Series connection of thyristors is typically used for high voltage DC transmission rather than standard bidirectional AC control. Bipolar junction transistors operate on different physical principles and do not form the structural basis of standard triacs.
- Subject
- Engineering
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- Electrical Engineering
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- medium
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