Semiconductor Devices (part 5/6): Thyristors & TRIACs

This video is part 5/6 of the week 4 series “Semiconductor Devices” and continues directly on from the week 3 series “Introduction to Semiconductors”.
These videos are part of a full Introduction to Electronics course (PHY2006) for students at the Maastricht Science Programme, Maastricht University. This course has a co-requisite of a practical course (PRA2006) in which theory is applied to circuit building and testing in the laboratory.
These videos are merely one part of the overall educational experience and are supplemented throughout the period with tutorials, exercises, activities, lecture slides, downloads of all important information and worksheets, as well as additional support from tutors and course coordinators.
By the end of this topic, you should be able to:
• Describe how PN junctions function in equilibrium, forward bias and reverse bias by sketching band diagrams.
• Sketch the IV characteristics of diodes, thyristors and TRIACs and describe how these change under different biasing conditions.
• Identify the function of transistors in various circuits configurations, applied either as switches or for amplification.
• Explain how thyristors and TRIACS can be used in circuits as switches and for phase control.
• Sketch and calculate the output voltages or gain of opamps in controlled-gain circuits, when given information about the input voltage and resistor values (or vice versa).
If you’re interested in a degree in Maastricht, check out our official webpages:
www.maastricht... www.maastricht...

[@davidmonk7773]

Please please continue to make videos like this. you’ve explained this in a way that I've understood something that I couldn't before, i found this at school too, 1 teacher out of 15 would be able to unlock my brain, when it happens it feels fantastic 😊

[@donna.carroll]

thanks so much for your wonderful feedback, I'm so pleased you liked the explanation! I hope to start making more videos soon, thanks to motivating comments like yours!

[@democracyforall]

@@donna.carrollThanks for such a wonderful lecture and video. Just wanted to ask you one more thing. If I have a relay which is in closed normally and the it opens when the extra pin i.e the third one is powered. In the normal closed position I can pass dc current through it but if I powered the third pin which opens it will it open it if it has dc current flowing through it already in the normally closed position???

[@ELECTRONICS_LAB360]

Triac connection is totally wrong.!

[@wlondoner]

Amazing explanation. You solved the mystery of thyristor and triac in less than 12min. Thank you soo much

[@donna.carroll]

thanks for your kind feedback!

[@CZYB-vg2xi]

This has saved me hours of searching for explanations. You make it easier to understand

[@ElectrifiedStud]

You are doing a wonderful job at teaching. Keep up the good work and wish you get what you really deserve. Thanks for reteaching my partially lost knowledge that was learnt a long time back. Cheers!

[@CZYB-vg2xi]

What a teacher💯

[@valentinaslau]

The triac circuit shown around minute 10 essentially makes a short over the triac and thus renders it unusable. If the lower right line would be removed, then yes, it would work as intended.

[@Damian-om7op]

Yup, you're right.

[@PAPYRSEH]

I subscribed, because you don't read what to say on your tablet, thank you for being a human and for your scientific work 🤝

[@donna.carroll]

Thanks so much for your lovely feedback

[@Savan_Triveda]

Wow, I fall in love with TRIACS. I never thought thats possible.

[@masakari6922]

Damn i wish you were my professor back when i first started learning this stuff lol i would have had a better understanding

[@donna.carroll]

thanks so much for your lovely feedback!

[@CZYB-vg2xi]

100 percent

[@terrymaker4781]

Excellent video! Clear and concise! I hope you continue your videos!

[@donna.carroll]

thanks so much for the lovely feedback

[@alaahussin7815]

Great!

[@orveahava]

Great easy to understand video. Thanks.

[@donna.carroll]

thanks for watching and taking the time to comment

[@natanaelalfaputra_te_0559]

to set the timing of the pulse, you can use zero crossing detector. That makes the pulse will tirgger, always on the same spot of sine wave, actually at zero point. Thanks a lot for the explanation miss..

[@igorzherebiatev5751]

Hi. Liked and subscribed. I had got a question about a possibility of using the triac without the db3 attached to the gate. After about a month of searching I finally found the answer. In your video. Thank you. You also explained how my old experimental device worked.

[@erhman2004]

This is what Bob Carver used in some of his audio amplifier power supply designs.

[@andersonpinesso2812]

Thank you very much for this very clear explanation.

[@donna.carroll]

thanks, glad it's helpful!

[@towers2000]

It seens the circuit you draw from minute 8th onwards will be always turned on, regardless of the triac state.

[@jamescaperelliiii4620]

The triac circuit is technically not correct for the operation being described. Closing the switch is also completing the electrical path for the motor / load regardless of the triac state. That circuit as drawn is fraught with errors.

[@donna.carroll]

Yes indeed! In practice (in a real circuit) you wouldn't build it exactly like this for many reasons, but for this example, it's just to gain a basic understanding of how the device might function in theory. Thanks for watching and commenting, much appreciated

[@user-mr3mf8lo7y]

Great explanation.

[@donna.carroll]

thanks for watching and taking the time to comment!

[@archanatotekar671]

Nicely explained! Thanks!

[@anjanasadaruvan5306]

Tnks mis

[@donna.carroll]

you're welcome! thanks for the nice comment

[@msnextone1017]

Interesting situacion, scenario, id say..😅, very simple and straightforward explanation 💞, than you so much.

[@steveman1982]

Now i understand the parts a bit better of the lamp I'm trying to fix. Only goes on full blast, with the variable resistor in any position. Thanks!

[@DjeDrie]

have u fixed it because im having trouble with a dremel tool with on max speed ??

[@donna.carroll]

Glad I could be of help! Sounds to me like your variable resistor might be shorted which means the capacitor doesn't take any time to charge, hence the full signal is going through the triac all of the time

[@donna.carroll]

@@DjeDrie this could be the same fault - the variable resistor / potentiometer. Of course, sometimes the TRIACs themselves also fail

[@louco2]

If the capacitor where not there/open you would also have the full voltage in the gate regardless of how much resistance in the potentiometer?? Thank you for taking the time to do these videos by the way!! @@donna.carroll

[@TheAnthroheart]

Awesomeness!

[@jorgeluispereiradasilva5123]

Thank You. Good Video I believe that it will be applicable in Electric Cars. I have just observed in the video 10:51 moment that a resistor is missing maybe between Gate and Cathode of triac to be connected to the diode . Could you make more videos like this? Very good explanation thank you again.

[@DonatoGreco]

Nice and thorough explanation, but @8:00 I find an error in the schematic since the bottom right DIRECT connection of the switch with AC supply completely bypasses the Thyristor, it shouldn't exist and your analysis would be RIGHT

[@ChandrashekarCN]

💖💖💖💖

[@ishakboussalia1555]

I know that gate should be connected in A2 side not A1 . I am confusing here . The question is the gate on line side or the natural?

[@brucecorbettn9bh398]

I remember doing this at Joliet Junior College in Joliet IL around 1971 using a gas filled tube. What is that tube called?

[@donna.carroll]

probably a thyratron, right? en.wikipedia.org/wiki/Thyratron#:~:text=A%20thyratron%20is%20a%20type,phenomenon%20known%20as%20Townsend%20discharge.

[@donna.carroll]

thanks for watching!

[@lagossmartmeterhackathonte8928]

Triode vacuum tube

[@anjanasadaruvan5306]

Pilss 230v universal motor soft start tracs use circuit

[@victimovtalent6036]

mam..using SCR and sawtooth wave form for drill to reduce rotation speed and not lost torque like as TRIAC does

[@donna.carroll]

some motors use two separate windings to adjust rotation speed instead of a TRIAC, that could be a solution

[@victimovtalent6036]

@@donna.carroll mam we talking about drill 😌

[@rideikarim9540]

question, at kzbin.info/www/bejne/ZnjKiKl-Z9KMbpI , how can i replace the variable resistor, with something, ( may be transistor,) so i can control the current from other source, let say micro controller (arduino which is has analog output)

[@DawoodKhan-fg2pb]

hello

[@donna.carroll]

and hello to you! 😀