This content has been recreated as an eBook for easy offline reference - part one is available now for free: bit.ly/3tpT0PS Also check out the Candy Thief Alarm project Karen created with her newfound transistors knowledge bit.ly/3jlR32f Or the conversation between Karen and James (aka thebaldengineer) about transistors bit.ly/36HoGXr
I swear to god I just spent 15 minutes reading about how transistors work but 3 minutes into this video I feel a lot more enlightened. The article never even mentioned why it’s called a transistor.
Excellent MNOMIC Andreas, if you have any more; indeed if anyone has any more, please leave us them in the comments. They are really helpful. Thanks, hats off to you and cheers.
Andreas. Thank you. This was the question raised in the mind when i was listening the lecture. How to keep in memory the arrow direction.?..you answered. Thank you
Hello, first time I find a girl who works in the field of electronics, I am happy For watching your wonderful channel, greetings to you, my dear sister Very nice 👍👍
Thanks, this is the only video that makes it super simple to understand without the presenters stroking their ego by trying to sound smart by overcomplicating things.
2:38 is this supposed to be stated as 'while a signal current flows from the base to the emitter'? as opposed to flowing from the base to the collector?
Correct me if I'm wrong but at 4:43 when describing the the pnp BJT, shouldn't it be maintained that Veb >= 0.7v ? The equation stated says Vce - Vbe >= 0.7v which is the same as Vcb >= 0.7v
Yes, something is wrong here. If I take 2SA1015 max specs it says VCE=-50V VEB=-5V, running it with emitter at 18V and collector grounded as I do, I would not be able to shut it off at all, if the formula in video is correct, since I can never bring VBE close to 18V (I'll leave sign convention out of consideration here)
There is an error here for PNP, I think, it is still VBE that should exceed 0.7 V (or, more accurately, should be less than -0.7 V, i.e larger than 0.7 by magnitude). If you think about each np junction as a diode, it is just a direction that changes in pnp but still same voltage to start moving electrons/holes across the BE junction, not that you suddenly need VBE close to VCE (determined by external conditions !)
4:20 This is incorrect for the diagram you've given. You will only loose .7v from the circuit if your collector and base junctions are supplied from the same source. In your diagram you'll only loose about 50mv (Assuming a 2n3904 and 1k load with some amount of base resistance) in the collector to emitter channel as you are supplying the base current separately from the collector.
I caught that as well. the Vce is (Vcc-Vrc)/R1 - Vled = [(Vcc-(Ic*R1))/R1] - the Vled drop from the LED not the .7v from the Vbe. Also BJTs are current controlled not voltage controlled. She is explaining the switching effect as if they are JFETs or MOSFETs.....which are voltage controlled semiconductors. Try applying 7v to the base of a BJT without a resistor to limit the current flow and watch it burnout instantly.
So then for a PNP example you give, the base-emitter needs a power supply of at least 8.3 volts or you wouldn’t be able to shut the transistor off? Does this mean that if you were using a microcontroller that is only capable of emitting 3.3 volts, and you wanted to use one of it’s output pins as a base emittor, to a transistor powered by 9 volts, you could use an npn transistor, but not a pnp transistor?
you lost me at 2:16 so why are the diode arrows different and the rest showing different positions in where the common is on the transistor? are they different or the same one? but just flipped upside down?
Great refresher. I used to dabble with semi conductors as a kid, but didn't really understand how they worked. This video brought it all back for me...thanks!
i finally felt i understood the transistor basics now. wow that took some years to grip but this video confirmed everything ive understood and by watching this i now got it, thanks
You can't tell physically, they're often supplied in identical packages. You need to look up the product code, or test it in a meter, or just try passing a base-emitter current and see which way around it needs to flow.
Why 0.7 VDC EB voltage? Because of the material the transistor is made of. Silicon transistors require 0.7 VDC EB bias voltage to turn on. Germanium semiconductor components require 0.3 VDC bias voltage.
Thank you for this video. Well explained and easy to understand. You are the personal teacher of so many people that acess youtube. You give joy, and self fullfilment to so many people. I cherish you in my mind.
I've spent the last week trying to figure out transistors, reading a lot of material and this was one of the most helpful resources in understanding them. Thank you so much for sharing!
we owe everything to these transistors. I was working as a tube tech when these devices started to hit the market. like in all things the new replaces the old. as for npn and pnp it depends on the circuit I design. thus, a super stable low frequency tunable osc requires a small load transistor in a reverse polarity configuration.
The diagram at 2:40, so it is okay to have the small 'Signal Current' ground tied into the same 'Main Current' ground? These two parts obviously keep to their own parts of the circuit. The Main current must not travel into the SIgnal current part of the circuit.
Hello ... I wanted to ask you .. if you know a page that has a new and modern parts datasheet, introduce it to me ... Because we are witnessing less scrutiny of parts recently .... Thank you
Will we see transistors used in a circuit in a future episode? This information is great. I haven't had much exposure to working with transistors so I'll be sure to review this video back couple of times to make sure I understand everything.
Excellent video but a bit hard to follow on its own, without looking at the "previous video" you refer to. I'd suggest providing a link to it for ease of use. Cheers!
Miss please tell me what will be the voltage ,current of base ,emmiter, collector if I connect mosfet in parallel on one side is 50 mosfet d718 and 50 on another side I want to make push and pull power amplifier please help me
Think of the base as a little push button which controls a massive flow of a river (from collector to emitter) Though it does not take much force to push the button in, the harder you push the button in, the greater the flow of the river (from collector to emitter). By connecting the output of one transistor (massive flow) to the base (push button) of another transistor, you are greatly amplifying the force with which you are pushing in the button.
@@freddykrueger6571 Oh i see, thanks alot for the explanation. I was under the impression that the current 'dripped' out of the base. So i felt that connecting a emitter to a base would yield opposing flows. Does the base have different flow directions for PNP and NPN?
so pretty to use a transistor as a switch u have to have a small current flow from the base to allow a larger current to flow from collector to emitter? and does that require two separate voltage sources?
"0.7 v is lost to heat" - No, heat is an energy loss and is equal to Vce x Ic (voltage times current).Also, Vce is nor 8.3 volts. It is 9 volts minus the voltage drop across the LED and series resistor. You have not calculated what Ic is, and therefore cannot state any of these numbers.
Yes, that was a wrong circuit analysis. When the transistor enters saturation mode, there is a Vce voltage drop provided by the manufacturer. The remaining is divided on the other elements around the circuit loop (kirchhoff's voltage law).
Tubes were much nore forgiving. I began designing tube circuits and if you make a mistake like grounding a grid, the plate glows cherry red hahh With a transistor, it just gets damaged and the circuit fails to operate leaving you with "ok why isnt this working?" Of course working with non lethal voltages has its benifits hahah Once I was working on a T.V. and had my hands inside while adjusting the time and my knuckle came to close to the horizontal output tube playe cap. That Hurt a LOT!!! I once got belted with the anode wire for a b&w crt. my jand felt like it was in a. Vise and then got smacked witha hammer! Ouch!
@@cat-lw6kq haha true. Ya gotta be careful with all.esp. now with close tolerances. Gone are point to point wiring where U can push components out if the way to get to a test point
@@rty1955 those old tube sets could take a lot of abuse. My teacher would show us what would happen if parts of a tv failed by removing tubes in a working set. The set was powered on and he would pull tubes one at a time. Try doing that with a transistor set.
@@cat-lw6kq how very true. He must of had silicon hands! I recall working in a broadcast T.V. studio where 21" Conrac monitors hung from the lighting grid. They replaced the covers with a screen mesh to allow for airflow. When i took it down for repair, I put it on the bench and powered it on. I could have baked a cake in that thing!
Great video. Really enjoying these. One small nitpick - at 2:39 I believe you really meant to say "the small signal current flows from the base to the emitter" not "from the base to the collector". The diagram however is correct.
Clearly, there are 2 main differences to understand Transistor Easily as Below : 1. We generally take positive output using a PNP Transistor. 2. We generally take Negative output using an NPN Transistor. Other Points : 1. Voltage flows from Collector to Emitter in NPN Transistor and Current flows in opposite direction. 2. Voltage flows from Emitter to Collector in PNP Transistor and Current flows in opposite direction. 1. When you would connect an LED using either a PNP or NPN transistor, take care of soldering LED's Anode and Cathode (K) Leg. It will be vice-versa. Any wrong connection would lead to no light from an LED. 2. Base to Emitter, always High Resistance. Base to Collector, always Low Resistance. Emitter to Collector Very High Resistance i.e. (Digital Meter must show ("1"). 3. In PNP Transistor, Ve > Vb by 0.7 Volt, Transistor turns on. Transistor works just like a Tubewell with a handle attached to it. You push up the handle slowly or fast, you would get that much amount of water in the bucket outside!
Without really knowing much of anything about electronics I could still get the idea of how this works. Fantastic....must resist temptation to binge watch entire series now....
At 2:36 you state that the base current flows from the base to the collector ....but your diagram shows the current flowing from the base to the emitter. Is this an error?
....and at 4:20 isn't the 8.3V the potential difference between the top of the LED and the collector? As current is flowing, there is a voltage drop across the LED and the resistor. So I would expect the Vce to be much less than 8.3V in the circuit as shown with the transistor turned on. Am I mistaken?
BEST EXPLANATION..., I TRULY HOPE THIS CHANNEL CAN GIVE ME A BETTER UNDERSTANDING OF ELECTRONICS AND HOW THEY ALL WORK TOGETHER THANK YOU I WILL BE SUBSCRIBING !
I did mechanical and he did electrical. I got more interested in electronics and he helped me a bit until I couldn't catch up with him especially when he started designing power amplifiers using Darlingtons . Oh yes! I manually etched a working stereo 20x20W. That was in 1981 and now I can try catch up.
Well. This video was very helpful! I thought to turn on an NPN transistor, I just needed to have .6v sitting at the base. Knowledge gap. Didn't realize it needed to flow through b to e. Its working now! Thanks
Hi Karen. I don't know much about transistors. I watched several of your videos on transistors. I do like it. I want to build a small circuit that I think it's doable by using transistors. Make it simple, I have a light in a box which I cannot see the light lit inside the box. If the light dies I don't know because it is in the box. So, I want to use a led to indicate the light is still alive. I cannot install the led in series with the main load circuit because the load could be a heavy load. So when watching your transistor illustration I think it's do able with a transistor using the same power source so if the main current is not flowing then the led turns off but I don't know how to do it. Could you please show me how to wire it. A diagram would be very helpful. Thank you so much.
Technically speaking, the arrows in the schematics refer to the direction of flow of 'positive charge carriers', which flow in the opposite direction to electron flow within the semiconductor. In all fairness, this video is an over-simplified description of how transistors function and does not cover the subject of charge carrier theory. My apologies if my overly-technical description sounds confusing 8)
@@kingsman428 A transistor is far more complex than the simple explanation . There is the so-called "leakage current between collector and base that are the result . It is a formidable concept that requires study to explain: see www.tutorialspoint.com/semiconductor_devices/semiconductor_devices_leakage_current.htm#:~:text=An%20important%20conduction%20limitation%20of%20PN%20junction%20diode%20is%20leakage%20current.&text=It%20is%20seen%20that%20in,dependent%20on%20minority%20current%20carriers.
If you discuss Darlington Pairs, it would also be useful to discuss Szicklai Pairs. I understand that the Darlington Pair discussion was a teaser. Therefore, I suggest a follow up in depth discussion of Darlington and Szicklai Pairs for a future video.
4:30 PNP transistor, ???? all we need do is turn the battery around so the (-) side goes to the base to make the PNP transistor turn on. The only difference between a PNP & NPN is that the PNP transistor needs a negative bias or B-E voltage to turn on.
I get the 0.7 Voltage Drop across Base-Emitter... however, how come there's NOT a 1.4 Voltage Drop from Collector-Emitter, since that passes thru 2 PN Junctions?
The junctions are in opposite direction, one pn, other np, so in ideal stable regime between emitter and collector you have drop of 0.7 V on one junction and rise of 0.7 volt on the other
@@dmitripogosian5084 Thanks for explaining this... now, I also sometimes see an equivalent Voltage Source of 0.2V at this same junction... can't figure-out why
Hi - The statement you are making around minutes:seconds 2:35 to 2:41 is not correct! You mean the base current is from the base to the emitter! Your diagram is correct but your explanation during these times in speech is wrong! There are two current loops B=>E and C => E. I also find that you are in a hurry. It would have been better to take it a bit slower. I have had to play and replay several times to fully understand what you are talking about! That's bearing in mind I already knew about transistors and wanted to remind myself of their operations. I wonder what a rookie (as you would call them in USA or a novice in English) would think watching this video! It would also be good to point out that this direction of current is called conventional current which again is really not the correct direction. The electron current is the correct direction and the reverse of the conventional current.
I would like to know is it a case that once 0.7v is at the base the the current which then flows between the emitter and collector a fixed rate or is it proportional to the voltage at the base; example if 2 volts was applied to the base would this increase the current flow to the emitter and collector or would it still be the same amount of gain as if 0.7V was at the base. I believe the term Iam thinking about is called voltage saturation, any ideas?
why my transistor keeps blowing when I am replace my light switch with it and turn on with a 0.7 volt battery, it splinters into many pieces and fly in all directions with a big spark? The light bulb is 240V 100 watt bulb. Oh and it smokes as well. Do I need a heat sink may be.
At 2:39 you say the signal current flows from base to collector, but then the diagram and your next statement says it flows from base to emitter? That confused me.
Hi, how are you. I am really flattered. You explained very nicely and impressively. I am 60 years old man with 42 yeas experience in technical work and I have many Invented designs and many mega projects but I am living in the environment Where is no support from the government for the real visionary people. Each day I am thinking that life is not to waste and each breath is to find out the Real good way to facilitate the whole mankind, but the people who has Power but they don't have a good visionary mind. If I were sponsored by the hogher level authority, I am 100% sure that My only One development program can bring wealth to the whole world but, I am helpless to show because there is no support and sponsor for the true visionary mind people. I am very much impressed from your ability to explain and the real Seekers. Love you so very much, ❤ may God bless you.❤❤❤
A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit
if both the emitter and collector are the same N or P, how do they differ? what makes one an emitter and one a collector? could your make your own transistor using 2 diodes or is there something fundamental that i am missing.
You cannot make your own transistor using two diodes because they need to share the same junctions with the common region. Also, the emitter and collector may have the same circuit diagram and you can actually wire them up backwards and they will still likely function (perhaps poorly), but they are usually not the same. Transistor manufacturers will often dope them differently so that you get the best performance using them the way that they are labeled. Also, you aren't guaranteed that your discrete "transistor" isn't actually made up of more than one transistor to improve performance (ex: darlington). So it is best to use it as labeled.
This content has been recreated as an eBook for easy offline reference - part one is available now for free: bit.ly/3tpT0PS
Also check out the Candy Thief Alarm project Karen created with her newfound transistors knowledge bit.ly/3jlR32f
Or the conversation between Karen and James (aka thebaldengineer) about transistors bit.ly/36HoGXr
Hey, your ebook link doesn't appear to be working :/
element14 presents, go to hell.
You literally taught me in 7 minutes what my instructor failed to do in an hour.
You too fast
I swear to god I just spent 15 minutes reading about how transistors work but 3 minutes into this video I feel a lot more enlightened. The article never even mentioned why it’s called a transistor.
Maybe check the first thing she says at the :25 mark
@@bradzimmerman306 how does it feel to be stupid?
@@entidade1000 I don’t know. Tell me how you feel.
PNP = Points iN Permanently
NPN = Never Points iN
this may help with reading schematics.
i remember this in class.
wow.. really helpful
Excellent MNOMIC Andreas, if you have any more; indeed if anyone has any more, please leave us them in the comments. They are really helpful. Thanks, hats off to you and cheers.
Thanks Stevens
Andreas. Thank you. This was the question raised in the mind when i was listening the lecture. How to keep in memory the arrow direction.?..you answered. Thank you
Hello, first time I find a girl who works in the field of electronics, I am happy For watching your wonderful channel, greetings to you, my dear sister Very nice 👍👍
Just a small correction.
It is called bipolar because it depends on both electrons and holes! not because it has 2 pn junctions.
Thanks, this is the only video that makes it super simple to understand without the presenters stroking their ego by trying to sound smart by overcomplicating things.
2:38 is this supposed to be stated as 'while a signal current flows from the base to the emitter'? as opposed to flowing from the base to the collector?
Correct me if I'm wrong but at 4:43 when describing the the pnp BJT, shouldn't it be maintained that Veb >= 0.7v ? The equation stated says Vce - Vbe >= 0.7v which is the same as Vcb >= 0.7v
Rascul It should state that Vbe
Yes, something is wrong here. If I take 2SA1015 max specs it says VCE=-50V VEB=-5V, running it with emitter at 18V and collector grounded as I do, I would not be able to shut it off at all, if the formula in video is correct, since I can never bring VBE close to 18V (I'll leave sign convention out of consideration here)
5:22 so for PNP: does it means if there's only VCE closed circuit connected to PNP without VBE circuit - will VCE works? (Since 9V - 0V > 0.7V)
There is an error here for PNP, I think, it is still VBE that should exceed 0.7 V (or, more accurately, should be less than -0.7 V, i.e larger than 0.7 by magnitude). If you think about each np junction as a diode, it is just a direction that changes in pnp but still same voltage to start moving electrons/holes across the BE junction, not that you suddenly need VBE close to VCE (determined by external conditions !)
4:20 This is incorrect for the diagram you've given. You will only loose .7v from the circuit if your collector and base junctions are supplied from the same source. In your diagram you'll only loose about 50mv (Assuming a 2n3904 and 1k load with some amount of base resistance) in the collector to emitter channel as you are supplying the base current separately from the collector.
I caught that as well. the Vce is (Vcc-Vrc)/R1 - Vled = [(Vcc-(Ic*R1))/R1] - the Vled drop from the LED not the .7v from the Vbe. Also BJTs are current controlled not voltage controlled. She is explaining the switching effect as if they are JFETs or MOSFETs.....which are voltage controlled semiconductors. Try applying 7v to the base of a BJT without a resistor to limit the current flow and watch it burnout instantly.
I think this is the first time I've ever been able to wrap my head around this.
This is an AWESOME lesson. You pulled back the veil that has shrouded this in mystery to me for years.
I am a new learner and found this video very useful and informative. The pace was perfect for me.
what is your progress at the moment??
you are heaven sent.... Got D's and E's in physics bt now that i need PCB skills in real life you make it much much easier... thanks
So then for a PNP example you give, the base-emitter needs a power supply of at least 8.3 volts or you wouldn’t be able to shut the transistor off? Does this mean that if you were using a microcontroller that is only capable of emitting 3.3 volts, and you wanted to use one of it’s output pins as a base emittor, to a transistor powered by 9 volts, you could use an npn transistor, but not a pnp transistor?
In just 7 min you cleared every thing. Teaching is an art and that's true.
In the circuit diagramm i haven't got the battery 0.7, and the resistance after the diode to limit current in the led? Or in the transistor?
Excellent video.
Easy to understand. Logically ordered.
Very professional.
Like listening to a talented engineering expert.
This is one of the top electronics channels out there
you lost me at 2:16 so why are the diode arrows different and the rest showing different positions in where the common is on the transistor? are they different or the same one? but just flipped upside down?
Great refresher. I used to dabble with semi conductors as a kid, but didn't really understand how they worked. This video brought it all back for me...thanks!
can i ask why does the s8550 transistor leak 5v from emitter to collector when u apply 12v on emitter with no load
i finally felt i understood the transistor basics now. wow that took some years to grip but this video confirmed everything ive understood and by watching this i now got it, thanks
4:25 shouldn't you account for the voltage dropped by R1 too?
At 2:40 you say that the signal current flows from the base to the collector but I think you mean from the base to the emitter.
Can you please mention how can we physically distinguish between a PNP and NPN transistors
You can't tell physically, they're often supplied in identical packages. You need to look up the product code, or test it in a meter, or just try passing a base-emitter current and see which way around it needs to flow.
i did not quite get how the signal current flows,is it from base to collector OR from base to emitter
Why 0.7 VDC EB voltage? Because of the material the transistor is made of. Silicon transistors require 0.7 VDC EB bias voltage to turn on. Germanium semiconductor components require 0.3 VDC bias voltage.
But now a days, Gallium Arsenide is used as strata, then what is Vbe?
Thank you for this video. Well explained and easy to understand.
You are the personal teacher of so many people that acess youtube.
You give joy, and self fullfilment to so many people. I cherish you in my mind.
I've spent the last week trying to figure out transistors, reading a lot of material and this was one of the most helpful resources in understanding them. Thank you so much for sharing!
Me too
Expecially for the PNP
we owe everything to these transistors. I was working as a tube tech when these devices started to hit the market. like in all things the new replaces the old. as for npn and pnp it depends on the circuit I design. thus, a super stable low frequency tunable osc requires a small load transistor in a reverse polarity configuration.
The diagram at 2:40, so it is okay to have the small 'Signal Current' ground tied into the same 'Main Current' ground? These two parts obviously keep to their own parts of the circuit. The Main current must not travel into the SIgnal current part of the circuit.
Hello ... I wanted to ask you .. if you know a page that has a new and modern parts datasheet, introduce it to me ... Because we are witnessing less scrutiny of parts recently .... Thank you
Will we see transistors used in a circuit in a future episode? This information is great. I haven't had much exposure to working with transistors so I'll be sure to review this video back couple of times to make sure I understand everything.
Yup! Coming up next Wednesday! I usually do episodes in pairs, first a lesson video, followed by a project using what was talked about in the lesson.
Thanks sister. U explained every thing in a very understandable manner.pl extend your lesson further for novice and other interested.
Excellent video but a bit hard to follow on its own, without looking at the "previous video" you refer to. I'd suggest providing a link to it for ease of use. Cheers!
Miss please tell me what will be the voltage ,current of base ,emmiter, collector if I connect mosfet in parallel on one side is 50 mosfet d718 and 50 on another side I want to make push and pull power amplifier please help me
In a darlington pair why would you connect the emmiter of the first one to the base of the second one instead of the collector of the second one?
Think of the base as a little push button which controls a massive flow of a river (from collector to emitter)
Though it does not take much force to push the button in, the harder you push the button in, the greater the flow of the river (from collector to emitter).
By connecting the output of one transistor (massive flow) to the base (push button) of another transistor, you are greatly amplifying the force with which you are pushing in the button.
@@freddykrueger6571 Oh i see, thanks alot for the explanation. I was under the impression that the current 'dripped' out of the base. So i felt that connecting a emitter to a base would yield opposing flows. Does the base have different flow directions for PNP and NPN?
so pretty to use a transistor as a switch u have to have a small current flow from the base to allow a larger current to flow from collector to emitter?
and does that require two separate voltage sources?
How do you know how much voltage or current a transister can take?
Please also explains about voltage amplification & modulation by using PNP & NPN Transistors
"0.7 v is lost to heat" - No, heat is an energy loss and is equal to Vce x Ic (voltage times current).Also, Vce is nor 8.3 volts. It is 9 volts minus the voltage drop across the LED and series resistor. You have not calculated what Ic is, and therefore cannot state any of these numbers.
Yes, that was a wrong circuit analysis. When the transistor enters saturation mode, there is a Vce voltage drop provided by the manufacturer. The remaining is divided on the other elements around the circuit loop (kirchhoff's voltage law).
@@habotssar8429 so basically if the transistor is on it acts like a resistor which drops a fixed voltage between collector and emitter?
Stated with confidence too 😂😂
@1:31 of this video, kindly check the drawing you have presented. The symbol is meant for NPN whereas it shows PNP. Please correct me if wrong
it is a great Explanation. when somebody explainsa this way Electronic circuits become easier to understand. I'm a beginner. Thank you very much.
You have the most perfect explanation about transistor using precise circuits
at 1:31 it's wrong. The diode allows current follow form p-type region to n-type region
I learned vacuum tubes first and some of the older books compare a tube to a transistor. So that made it easy for me to learn transistors.
Tubes were much nore forgiving. I began designing tube circuits and if you make a mistake like grounding a grid, the plate glows cherry red hahh
With a transistor, it just gets damaged and the circuit fails to operate leaving you with "ok why isnt this working?"
Of course working with non lethal voltages has its benifits hahah
Once I was working on a T.V. and had my hands inside while adjusting the time and my knuckle came to close to the horizontal output tube playe cap. That Hurt a LOT!!! I once got belted with the anode wire for a b&w crt. my jand felt like it was in a. Vise and then got smacked witha hammer! Ouch!
@@rty1955 I've worked on both. Transistor sets you slip with you probe and short something and you blow out half the set.
@@cat-lw6kq haha true. Ya gotta be careful with all.esp. now with close tolerances. Gone are point to point wiring where U can push components out if the way to get to a test point
@@rty1955 those old tube sets could take a lot of abuse. My teacher would show us what would happen if parts of a tv failed by removing tubes in a working set. The set was powered on and he would pull tubes one at a time. Try doing that with a transistor set.
@@cat-lw6kq how very true. He must of had silicon hands! I recall working in a broadcast T.V. studio where 21" Conrac monitors hung from the lighting grid. They replaced the covers with a screen mesh to allow for airflow. When i took it down for repair, I put it on the bench and powered it on. I could have baked a cake in that thing!
Great video. Really enjoying these. One small nitpick - at 2:39 I believe you really meant to say "the small signal current flows from the base to the emitter" not "from the base to the collector". The diagram however is correct.
Great
I just noticed that. I was like, "Am I misunderstanding??" Guess she just misspoke.
Clearly, there are 2 main differences to understand Transistor Easily as Below :
1. We generally take positive output using a PNP Transistor.
2. We generally take Negative output using an NPN Transistor.
Other Points :
1. Voltage flows from Collector to Emitter in NPN Transistor and Current flows in opposite direction.
2. Voltage flows from Emitter to Collector in PNP Transistor and Current flows in opposite direction.
1. When you would connect an LED using either a PNP or NPN transistor, take care of soldering LED's Anode and Cathode (K) Leg. It will be vice-versa. Any wrong connection would lead to no light from an LED.
2. Base to Emitter, always High Resistance.
Base to Collector, always Low Resistance.
Emitter to Collector Very High Resistance i.e. (Digital Meter must show ("1").
3. In PNP Transistor, Ve > Vb by 0.7 Volt, Transistor turns on.
Transistor works just like a Tubewell with a handle attached to it. You push up the handle slowly or fast, you would get that much amount of water in the bucket outside!
Fast explanation for this novice, but upped my transistor knowledge by 80%.
Without really knowing much of anything about electronics I could still get the idea of how this works. Fantastic....must resist temptation to binge watch entire series now....
This lady is really cool, Im binge watching her tutorials. Excellent teacher !
At 2:36 you state that the base current flows from the base to the collector ....but your diagram shows the current flowing from the base to the emitter. Is this an error?
....and at 4:20 isn't the 8.3V the potential difference between the top of the LED and the collector? As current is flowing, there is a voltage drop across the LED and the resistor. So I would expect the Vce to be much less than 8.3V in the circuit as shown with the transistor turned on. Am I mistaken?
BEST EXPLANATION..., I TRULY HOPE THIS CHANNEL CAN GIVE ME A BETTER UNDERSTANDING OF ELECTRONICS AND HOW THEY ALL WORK TOGETHER THANK YOU I WILL BE SUBSCRIBING !
I've put a transistor circuit amp together but it would not turn on please tell me what's happened ?
I did mechanical and he did electrical. I got more interested in electronics and he helped me a bit until I couldn't catch up with him especially when he started designing power amplifiers using Darlingtons . Oh yes! I manually etched a working stereo 20x20W. That was in 1981 and now I can try catch up.
This is the most amazing explanation of transistors that I have ever run across! Thank you!
Well. This video was very helpful! I thought to turn on an NPN transistor, I just needed to have .6v sitting at the base. Knowledge gap. Didn't realize it needed to flow through b to e. Its working now! Thanks
Hi Karen. I don't know much about transistors. I watched several of your videos on transistors. I do like it. I want to build a small circuit that I think it's doable by using transistors. Make it simple, I have a light in a box which I cannot see the light lit inside the box. If the light dies I don't know because it is in the box. So, I want to use a led to indicate the light is still alive. I cannot install the led in series with the main load circuit because the load could be a heavy load. So when watching your transistor illustration I think it's do able with a transistor using the same power source so if the main current is not flowing then the led turns off but I don't know how to do it. Could you please show me how to wire it. A diagram would be very helpful. Thank you so much.
I wish you were my university professor, because you just explained something better in 7 minutes than they did in 7 hours' worth of lectures.
2:37 Your voice over doesn't match your schematic -- You incorrectly say that "current flows from the base to the collector"
Well, technically speaking, current *never* flows under any conditions.
Yeah, that has to be a mistake. Should have been base to emitter.
Technically speaking, the arrows in the schematics refer to the direction of flow of 'positive charge carriers', which flow in the opposite direction to electron flow within the semiconductor. In all fairness, this video is an over-simplified description of how transistors function and does not cover the subject of charge carrier theory. My apologies if my overly-technical description sounds confusing 8)
@@kingsman428 A transistor is far more complex than the simple explanation . There is the so-called "leakage current between collector and base that are the result . It is a formidable concept that requires study to explain: see
www.tutorialspoint.com/semiconductor_devices/semiconductor_devices_leakage_current.htm#:~:text=An%20important%20conduction%20limitation%20of%20PN%20junction%20diode%20is%20leakage%20current.&text=It%20is%20seen%20that%20in,dependent%20on%20minority%20current%20carriers.
Joseph Rutha Unless specifically stated, current refers to Conventional Current, not charge carriers. That’s the whole point of having a convention.
The way in which you are teaching is lajavab
If you discuss Darlington Pairs, it would also be useful to discuss Szicklai Pairs. I understand that the Darlington Pair discussion was a teaser. Therefore, I suggest a follow up in depth discussion of Darlington and Szicklai Pairs for a future video.
4:30 PNP transistor, ???? all we need do is turn the battery around so the (-) side goes to the base to make the PNP transistor turn on. The only difference between a PNP & NPN is that the PNP transistor needs a negative bias or B-E voltage to turn on.
...and the fact that due to tecnology issues it's easier to produce fast and highpower NPN than PNP with same characteristics
I also read that design engineers often used NPN's so it became more popular.
Usually, not always, NPN is used to switch a circuit on the ground side. PNP is used to switch the circuit on the supply side.
npn transistor charge carriers are more mobile, so they are 'faster'.
cat 11 Yeah, this whole PNP section is complete wrong from start to finish.
Can I use two separate batteries or power sources. Onefor base signal and separate battery for collector emitters?
Excellent description & thanks
4:25 isn't the 0.7v VBE provided by the second power source to control the gate, why would it cause voltage drop for the 9v source?
Very nice information and presentation.
Best explanation i found thus far
I like your style of teaching...
so do we need 2 different energy sources for transistor biasing to work?
Amazing teacher!! Please keep up the good work 😊
excellent teaching Karen...Thank you!!
Excellent explanation
good one...simple & effective
02:38 you said SGNAL current from BASE to COLLECTOR??
I get the 0.7 Voltage Drop across Base-Emitter... however, how come there's NOT a 1.4 Voltage Drop from Collector-Emitter, since that passes thru 2 PN Junctions?
The junctions are in opposite direction, one pn, other np, so in ideal stable regime between emitter and collector you have drop of 0.7 V on one junction and rise of 0.7 volt on the other
@@dmitripogosian5084 Thanks for explaining this... now, I also sometimes see an equivalent Voltage Source of 0.2V at this same junction... can't figure-out why
Very nice 👌 thanks for educating the world 🙏
Is it possible to connect more than two transistors form a Darlington pair using npn transistors
naice Video , power goes to base , then to emiter, turn on transistor right , then power out on collector is that right
Hi - The statement you are making around minutes:seconds 2:35 to 2:41 is not correct! You mean the base current is from the base to the emitter! Your diagram is correct but your explanation during these times in speech is wrong! There are two current loops B=>E and C => E. I also find that you are in a hurry. It would have been better to take it a bit slower. I have had to play and replay several times to fully understand what you are talking about! That's bearing in mind I already knew about transistors and wanted to remind myself of their operations. I wonder what a rookie (as you would call them in USA or a novice in English) would think watching this video! It would also be good to point out that this direction of current is called conventional current which again is really not the correct direction. The electron current is the correct direction and the reverse of the conventional current.
With a non-science backgorund was struggling to get a minimum jibor-jabor explanation. Thank you so much
I would like to know is it a case that once 0.7v is at the base the the current which then flows between the emitter and collector a fixed rate or is it proportional to the voltage at the base; example if 2 volts was applied to the base would this increase the current flow to the emitter and collector or would it still be the same amount of gain as if 0.7V was at the base. I believe the term Iam thinking about is called voltage saturation, any ideas?
Super learning circuit man
Mam namaste
If possible please make videos on IGBT working principle 🙏
Can we use transistors for slow down of electronic energy meter
Best explanation I've heard so far, thanks.
what differetn btween 2SC2120 and C2120 transistor?
at 2:39 "the signal current flows from the base to the collector" should be "the signal [really, input] current flows from the base to the EMITTER"
Hi, I'm Tareq from Bangladesh. Thanks for your nice concept.
why my transistor keeps blowing when I am replace my light switch with it and turn on with a 0.7 volt battery, it splinters into many pieces and fly in all directions with a big spark? The light bulb is 240V 100 watt bulb. Oh and it smokes as well. Do I need a heat sink may be.
amazing, none of RUclipsr can explained except YOU, thanks
At 2:39 you say the signal current flows from base to collector, but then the diagram and your next statement says it flows from base to emitter? That confused me.
Hi, how are you.
I am really flattered. You explained very nicely and impressively.
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A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit
never seen such a well explained topic
Boa explicação prof mas como a prof explica um circuito sem o valor da resistência inserida no circuito ?
if both the emitter and collector are the same N or P, how do they differ? what makes one an emitter and one a collector? could your make your own transistor using 2 diodes or is there something fundamental that i am missing.
You cannot make your own transistor using two diodes because they need to share the same junctions with the common region. Also, the emitter and collector may have the same circuit diagram and you can actually wire them up backwards and they will still likely function (perhaps poorly), but they are usually not the same. Transistor manufacturers will often dope them differently so that you get the best performance using them the way that they are labeled. Also, you aren't guaranteed that your discrete "transistor" isn't actually made up of more than one transistor to improve performance (ex: darlington). So it is best to use it as labeled.
Why there is Voltage drop of 0.7v in Vbe and Vce is therefore 9-0.7 =8.3v ?.
OMG, thank you Karen.....a lot easier to understand than some of the stuff I've read!