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Thyristors
25 questions By Tony R. Kuphaldt
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Question 10 of 25
Label the terminals on a TRIAC with their proper designations:
Reveal answer
Notes:Ask your students where they found this information. Was it from a textbook, a datasheet, or some other source?
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Question 11 of 25
Explain how Silicon-Controlled Rectifiers (SCRs) differ from TRIACs, in terms of their respective behavior.
Reveal answerTRIACs are bilateral versions of SCRs.
Notes:The answer I give is very minimal by design. Students need to know what “bilateral” means with reference to electronic components, but this question provides a good opportunity for them to learn in case they don’t!
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Question 12 of 25
Some SCRs and TRIACs are advertised as sensitive-gate devices. What does this mean? What is the difference between a “sensitive gate” SCR and an SCR with a “non-sensitive gate”?
Reveal answerSCRs and TRIACs with “sensitive gates” resemble the idealized devices illustrated in textbooks. SCRs and TRIACs with “non-sensitive” gates are intentionally “desensitized” by the addition of an internal loading resistor connected to the gate terminal.
Follow-up question: where would this loading resistor be connected, in the following equivalent diagram for an SCR?
Notes:Ask your students why a thyristor such as an SCR or a TRIAC would need to be “de-sensitized” by the addition of a loading resistor? What is wrong with having a “sensitive” thyristor in a circuit?
Can someone please explain why do we need C1 capacitor in question 22 ? Circuit behaves exactly the same without it and I am confused about it’s purpose.