hello, i am a student in avionics systems and have found it hard to find any good explanation but must tell you that this is by far a very good explanation, thank you very much for the video, i will certainly look for more on you're channel.
thats why everyone studies in school till 12th grade. we even use addition and other basic mathematical operations in higher studies that we learnt in 1st grade@@sambhavkumar3865
Thanks so much for making this video! I was unclear what would happen when 2 diodes are placed back to back and your explanation made total sense. All the best to you and take care!
I've been confused with this topic for weeks...read the whole chapter too, still left me confused. Professor himself was confused what he was doing. Your 11 minute video cleared that all up. Thank you!
I was studying electronic 20 years ago and I didn't like as I didn't understand. Now I try to truly understand by searching in this UA-cam, and I now understand it very easy.
My Electronics course uses the book "Microelectronic Circuits" by Sedra & Smith. I am not really a fan of that book, since I find it dry and long-winded. I tend to prefer "Fundamentals Of Microelectronics" by Razavi - it's not QUITE the same content, but it's very similar, and includes typical topics such as diodes, transistors, small-signal models, rectifier circuits, and so on. It doesn't include zener diodes though, but it has a teaching style that I definitely prefer over Sedra & Smith. And also, Razavi himself has tons of videos on several Electronics courses, and has a pedagogical style much like The Organic Chemistry Tutor.
Current flows from negative post of battery to positive post. In a Forward biased diode, current flows against the arrow. You're backward in your theory.
@@bojangorgioski6353 Yeah that makes sense, but I’m always curious to know. I started replying to “Thanks, I have an exam coming up!”-type comments a while ago, and it’s led to some cool conversations…
Schools frown upon people with understanding teaching. They prefer people who needed to go to college and memorize answers without understanding to get an expensive piece of paper known as a "college diploma". 🙄
Althouh Zener Diodes are a bit old-school, they do have some modern applications. Back in the 80's, I worked on the first Transatlantic Fiber Optic Cable (TAT-8). It had repeaters every 25 Kilometers or so. The power for all the repeaters was several thousand Volts with each repeater having a Zener of the Voltage needed to power the Repeater in series with the Power. Think of it as a High Voltage supply with a string of Zeners in series with the output, each repeater having it's own Zener with the voltage and current being taken off across each Zener. Quite a simple setup, but it worked quite well.
I always see comments like this. And I always think.. then you've seen it once before then if you mention school. If you (someone) went to college with out any knowledge of the subject beforehand of course it will seem like they didn't teach it to you. Not that there aren't bad jobs done at colleges etc, but don't discount that you have to familiarize yourself with subjects before you can try to understand them.
I wish I found you 2 years ago so that this day would be different I was not afraid of this day so that I was not scared of what is going to happen next . I wish I found you before and thank you for what you have taught me still in 6 months
thanks mate this was a great video. nice to see it in the basic series circuit and then put into AC like that. i think the order you showed things is just the right way to do it. this is going into my permanent stash of educational resources
Good video on the zener diode Given the high voltage noted in the DC 50V example, you should have spent a moment to discuss P=I*V and the importance of the power ratings of the resistors. Some novice viewers might replicate this circuit on a breadboard using an improper 1/4W (.250) resistor and be alarmed by the magic smoke.
2:37 kinda blows my mind a bit. No current through the circuit, so I = 0, but 5v through the zener diode? But ohms law says v = i * r ? I was totally tracking until this point. Please help me understand what I'm missing. This is an excellent tutorial and already I now understand how a zener works to essentially siphon off a set amount of voltage from the circuit.
@Scott * Ohm's law is not applicable in semi conductor devices. * diodes when used under reverse bias do not let the current pass through it but when the reverse bias voltage exceeds the zener breakdown voltage, the current rises abruptly due to the high value of electric field across the junction which leads to breaking of covalant bonds of the atoms present at junction and many charge carriers emerge(set free) due breakage of the covalant bonds and a high current flows through the diode. But here zener voltage is 12 volt and the reverse bias voltage is 5 volt, therefore no breakdown will occur and it won't let any current pass through it and the voltage accross it would be 5 volt due to law of conservation of energy.
Try to think about it like this: imagine the current being very small instead of zero, let's say in nanoAmps. Imagine the zener diode as a resistance with a very high value, let's say in MegaOhms. And give the resistor a value of 1Kohm. Use ohm's law as usual, and it works fine.
Thank you very much from France, I had on one of my schematics at te output of one op amp 2 Zeners back to back as you show at the end of your video and I was wondering wat they were for, and now I understand Thank you so much keep going the same way.
my university should be giving you my tuition. professors are garbage. thank you so much. my lecture on this after never seeing a diode, was literally... "ok well, theres a voltage and a current, and its really quite simple lets move on" no examples, no explanation of anything. without your help i dont know what i would do.
I made my own 2 amp regulator using a zener , saved buying a to3 cased lm 780x device, just have to stick to a fixed input and output voltage so not to over current the zener.
What I didnt understand on minute 10:09 D2 is in reverse mode so opposite with the arrow of the current so negative voltage but why D1 is still negative? Shouldnt it be positive since the arrow of D1 is in the same direction with the current one and it is in the forward mode?
I am reluctant to subscribe since it seems all online pay subscription offerings make it very difficult to unsubscribe. But great videos, great channel!
Very well explained. One question though, the clipped wave in the end will peak at 12v, or Vs - 12v? And would the graph be 2 curves, peaking at Vs - 12v, separated by a gap?
Help please: at one point he says as the R (L) goes up the current through the load increases. I know this is a correct statement but I am having problems understanding why current would increase with higher resistance. This opposite of normal intuition and how things normally go. Also why would current go through the load at all when it can just go through the zener diode. It is like if you replaced the load and the zener with two parallel resistors, the lowest resistance will have the most current flow. Here it seems flipped.
You are Electronics god! Hoping you can help resolve my predicament. I have been desperately looking for an answer to WHY the voltage is constant across the diode? I have read and viewed every info possible including going deep into the science of Zener diodes but no one has explained the WHY. One of the reasons mentioned is that the diode regulates its internal resistance to maintain the voltage. How and Why does that occur? Can you please explain?
He means the voltage drop across the resistor will be 0V. The voltage drop across a resistor is V = IR, where I is the current through the resistor and R is the resistance. Since 0 A flows through the circuit, the voltage drop across the resistor is 0 V. However, the voltage of the top of the resistor relative to ground is 5V, which may be what's confusing you.
Additionally, it troubling to say something like "the voltage on the zener diode." When discussing voltage in regards to circuits, it typically means the voltage difference between two points. For instance, the voltage drop across a resistor means the voltage of one end of the resistor (relative to ground) minus the other end of the resistor (relative to ground). In this case, the voltage relative to ground on both ends of the resistor is 5V, the the voltage drop (5V - 5V) is equal to 0V. The zener diode - on the other hand - has one end connected directly to ground, so we know that end of the diode is at 0V (relative to ground since its grounded). Since the 5V hasn't dropped anywhere else in this series circuit, the entire 5V drop must be across the zener diode.
Good, if the out put is connected to a transistor base pin with proper connection then it will become a voltage regulator transistor, and also zener diodes were used for starting of electronic devices by feather touch switches.,pre determined settings for any comparator's also zener diodes were used, and zener diodes were regulating the complete globe in smps power supply put.
When looking at these problems, are we looking at hole flow, or are we looking at electron flow? Basically, will the current flow through the resistor first, or will it flow through the diet first?
I have a dumb question, if we have a circuit with two zener diodes and one resistor connected in series, both zener diodes are placed as reverse bias, if power source has voltage greater than one of the diode but smaller than the other diode, will there be no current flow in this circuit?
Thank you for a great video. You provided the explanation and formula for how one would calculate the current in the entire series circuit but how would you calculate the current in the diode versus the resistor?
First time watching one of your videos and really liked how simple your explanations are. I do have one question, what software do you use to make these?
Can you imagine the confusion that a young student would have after devouring and totally understanding your excellent tutorials on electrolytic and battery cells where it shows the current flowing INTO the cathode of the Battery (positive terminal), and then studying the electronic videos where it shows current flowing OUT OF the battery's positive terminal. We would explain it to the student as "oh, that's just conventional current". Conventional current he says ? What is that? What is flowing out of the positive terminal?" nothing is flowing out of the positive terminal son. " What do you mean nothing is flowing, why is it called a current if nothing is flowing
In theory current does flow from neg to pos. But since we didn't know that in the beginning engineers assumed it flowed from pos to neg and that's what practical electronics is based on. Confusing?? Yes...but so is the metric system and try studying transistor hole flow theory sometime. Some things just defy logic and theories quite often get disproved over time.
Hence his use of the phrase " *conventional* current", which does go from positive to negative, despite electrons moving the other way. You think current flow is electrons, but electrons have _negative_ charge. If I give you negative money , flow of money is from you to me. That's maths and physics. So I'll tell you what, _you_ convince the _scientists_ to rewrite Physics with the charge on the electron being positive, and _then_ the engineers will follow suit. Deal?
Even when I think I know I always learn something. I see in schematics around the resistor placed after the zener diode, I believe this does not affect the behaviour of the diode, does it?
is there also a diode liks this which regulates the voltage without dropping it by the regulated amount, for example if i have a 24v battery that goes to a zener diode and then to a solenoidvalve that needs 24v volts, is there some sort of diode that can only let the current through at 24v without taking 24 volts
Final Exams and Video Playlists: www.video-tutor.net/
So i spent 5yrs at the University and no lecturer could do what you just did in few minutes. Bravo to you.
You are a great teacher. You explain things concisely, clearly and in the right order to make it easy to understand.
hello, i am a student in avionics systems and have found it hard to find any good explanation but must tell you that this is by far a very good explanation, thank you very much for the video, i will certainly look for more on you're channel.
O_O i am a student of class 12th in india ( amazing that 12th study is used in engineering )
thats why everyone studies in school till 12th grade. we even use addition and other basic mathematical operations in higher studies that we learnt in 1st grade@@sambhavkumar3865
Test in 4 hours and this is a savior. Thank you!
Hope you're test went well..
@@Aspiringactor02 are you sure xD xD
How’d the test go!
how was the test?
Thanks for helping us to rectify our misunderstandings! All of your videos are wonderful, and thank you so much for making and sharing all of them.
such a calming, informative and easy to understand video about Zener diodes. Step by Step guiding us with a relief
Thanks so much for making this video! I was unclear what would happen when 2 diodes are placed back to back and your explanation made total sense. All the best to you and take care!
I've been confused with this topic for weeks...read the whole chapter too, still left me confused. Professor himself was confused what he was doing. Your 11 minute video cleared that all up. Thank you!
I was studying electronic 20 years ago and I didn't like as I didn't understand. Now I try to truly understand by searching in this UA-cam, and I now understand it very easy.
My Electronics course uses the book "Microelectronic Circuits" by Sedra & Smith.
I am not really a fan of that book, since I find it dry and long-winded.
I tend to prefer "Fundamentals Of Microelectronics" by Razavi - it's not QUITE the same content, but it's very similar, and includes typical topics such as diodes, transistors, small-signal models, rectifier circuits, and so on.
It doesn't include zener diodes though, but it has a teaching style that I definitely prefer over Sedra & Smith.
And also, Razavi himself has tons of videos on several Electronics courses, and has a pedagogical style much like The Organic Chemistry Tutor.
Really cleared up the mystery surrounding zener diodes for me. Really appreciate the vid!
Current flows from negative post of battery to positive post. In a Forward biased diode, current flows against the arrow. You're backward in your theory.
@@lawrencebaxter9448 this uses conventional flow, + to -
Your methods of explanations in basically all your videos have carried me in my courses of electrical / electronics theory. Thank you!
i have an exam in 2 days, this cleared up alot of things, thank you
How did your exam go?
@@bojangorgioski6353 Yeah that makes sense, but I’m always curious to know. I started replying to “Thanks, I have an exam coming up!”-type comments a while ago, and it’s led to some cool conversations…
1 hour for me
Dear Sir, you are a genious bcause despite being a organic chemistry tutor you know everything about Electronics which is totally different discipline
I’ve already noticed that people who have this kind of voice, the way the explain stuff is outstanding. I think about Brad Traversy.
Who is this guy,i have seen mulitple subjects and all of my problems are solved just by one guy,how much knowledge does he have haha
For the first time in my life realized about the zener diode🙏🙏🙏❤️❤️❤️
Same here 😀
If you are NOT in some school teaching, someone is not doing their job correctly.
UA-cam is a school, and he is certainly teaching.
Schools frown upon people with understanding teaching.
They prefer people who needed to go to college and memorize answers without understanding to get an expensive piece of paper known as a "college diploma". 🙄
I'm sure my teacher didn't teach me but you teach me . you are good teacher . God bless you.
Althouh Zener Diodes are a bit old-school, they do have some modern applications. Back in the 80's, I worked on the first Transatlantic Fiber Optic Cable (TAT-8). It had repeaters every 25 Kilometers or so. The power for all the repeaters was several thousand Volts with each repeater having a Zener of the Voltage needed to power the Repeater in series with the Power. Think of it as a High Voltage supply with a string of Zeners in series with the output, each repeater having it's own Zener with the voltage and current being taken off across each Zener. Quite a simple setup, but it worked quite well.
How come college professors in engineering can't explain this clearly? I know, it's just a rhetorical question.
They take special courses in making clear subjects unintelligible.....
Мне казалось, что такое бывает только в России. Я ошибался :)
To be able to easily explain something, you must first fully understand it yourself.
@@rozwell69 Einstein said, if you can not explain clearly, you don't understand it very clear.
I always see comments like this. And I always think.. then you've seen it once before then if you mention school. If you (someone) went to college with out any knowledge of the subject beforehand of course it will seem like they didn't teach it to you. Not that there aren't bad jobs done at colleges etc, but don't discount that you have to familiarize yourself with subjects before you can try to understand them.
Perfect !!!
No other video can explain zener in such a simple n perfect manner
Simplicity rocks 🎉
Its the best chanel on youtube for clearing concepts . Hats off😍😍
A very good lesson, even for someone with a weak English like me...
Thanks for the videos. Very easy to understand. Just started getting into electrics and this is very helpful.
youre content is life saving, THANK YOU!
Fantastic explain .. my first teacher in IT engineering collage❤
I wish I found you 2 years ago so that this day would be different I was not afraid of this day so that I was not scared of what is going to happen next . I wish I found you before and thank you for what you have taught me still in 6 months
thanks mate this was a great video. nice to see it in the basic series circuit and then put into AC like that. i think the order you showed things is just the right way to do it. this is going into my permanent stash of educational resources
Good video on the zener diode Given the high voltage noted in the DC 50V example, you should have spent a moment to discuss P=I*V and the importance of the power ratings of the resistors. Some novice viewers might replicate this circuit on a breadboard using an improper 1/4W (.250) resistor and be alarmed by the magic smoke.
I wish you were my professor. Your videos help me a lot.
Thank you very much. That last circuit explanation helped me a lot!
2:37 kinda blows my mind a bit. No current through the circuit, so I = 0, but 5v through the zener diode? But ohms law says v = i * r ? I was totally tracking until this point. Please help me understand what I'm missing. This is an excellent tutorial and already I now understand how a zener works to essentially siphon off a set amount of voltage from the circuit.
same scott
@Scott
* Ohm's law is not applicable in semi conductor devices.
* diodes when used under reverse bias do not let the current pass through it but when the reverse bias voltage exceeds the zener breakdown voltage, the current rises abruptly due to the high value of electric field across the junction which leads to breaking of covalant bonds of the atoms present at junction and many charge carriers emerge(set free) due breakage of the covalant bonds and a high current flows through the diode.
But here zener voltage is 12 volt and the reverse bias voltage is 5 volt, therefore no breakdown will occur and it won't let any current pass through it and the voltage accross it would be 5 volt due to law of conservation of energy.
Try to think about it like this: imagine the current being very small instead of zero, let's say in nanoAmps. Imagine the zener diode as a resistance with a very high value, let's say in MegaOhms. And give the resistor a value of 1Kohm. Use ohm's law as usual, and it works fine.
Thank you very much from France, I had on one of my schematics at te output of one op amp 2 Zeners back to back as you show at the end of your video and I was wondering wat they were for, and now I understand Thank you so much keep going the same way.
Hello
I assume the source of AC signal should be 40v pp to get this output. Otherwise the outcome would be 12.6v pp.
my university should be giving you my tuition. professors are garbage. thank you so much. my lecture on this after never seeing a diode, was literally...
"ok well, theres a voltage and a current, and its really quite simple lets move on"
no examples, no explanation of anything. without your help i dont know what i would do.
Excellent tutorial. The zener is underestimated in the age of the parasitical 78XX and it's siblings
Very clear explanation of zener diodes. Thank you.
The zener diode serves as a voltage regulat.
If the input voltage is less than the Zener volatge.No current will flow ❤
why would the forward biased diode have -0.6v in the example at 9:46?
So, in summary, can we say that a Zener diode acts as a voltage regulator?
Yes
Yeah it's called voltage regulator or breakdown diode
Yeah on breakdown it behave as a voltage source
great video. you are a good teacher.
This video is made for dummies like me. Thank you n happy Thanksgiving ☺️
Awwww..... don't call yourself that🥺🥺
I made my own 2 amp regulator using a zener , saved buying a to3 cased lm 780x device, just have to stick to a fixed input and output voltage so not to over current the zener.
And the channel's name is literally Organic Chemistry Tutor...
Thanks!
A great introduction to Zener diodes. Thanks a lot!
I wish you were my lecturer 47 years ago!
What I didnt understand on minute 10:09 D2 is in reverse mode so opposite with the arrow of the current so negative voltage but why D1 is still negative? Shouldnt it be positive since the arrow of D1 is in the same direction with the current one and it is in the forward mode?
Pal, I have the same question. Anyone to enlighten us?
yoo you literally got every topic i wanted to learn. thanks
I am reluctant to subscribe since it seems all online pay subscription offerings make it very difficult to unsubscribe. But great videos, great channel!
Crazy awesome tutorials. Good job man ✌
Resistance Voltages
The voltages in the circuit have to add up to the voltages of the battery
So in Example 3..It will be 50V-12V=38 V
Well done 👏✔ Tnx a lot. You are the best teacher. 👌
Min 9:45 where do you get -12V and-0.6 V from?
Thanks sir I really enjoy your lecture
Yes, I have learned a thing or two from your video!
Thank you 😊 excellent and simple teaching 👏
Very well explained.
One question though, the clipped wave in the end will peak at 12v, or Vs - 12v? And would the graph be 2 curves, peaking at Vs - 12v, separated by a gap?
this guy might actually save my end sems
Thanks a lot for showing me alone a difference
My favorite tutor
Help please: at one point he says as the R (L) goes up the current through the load increases.
I know this is a correct statement but I am having problems understanding why current would increase with higher resistance. This opposite of normal intuition and how things normally go.
Also why would current go through the load at all when it can just go through the zener diode.
It is like if you replaced the load and the zener with two parallel resistors, the lowest resistance will have the most current flow. Here it seems flipped.
Thanks!
Very good explanations,not very often seen on You tube..Thanks.
Thanks for your video it helps my channel grow.
Very comprehensive and easy to understand.
You are Electronics god! Hoping you can help resolve my predicament. I have been desperately looking for an answer to WHY the voltage is constant across the diode? I have read and viewed every info possible including going deep into the science of Zener diodes but no one has explained the WHY. One of the reasons mentioned is that the diode regulates its internal resistance to maintain the voltage. How and Why does that occur? Can you please explain?
2:24 why is resistor 0V? I learnt that even there is no current there will still be voltage right? Why is all the voltage on the zener diode?
exactly my question.
He means the voltage drop across the resistor will be 0V. The voltage drop across a resistor is V = IR, where I is the current through the resistor and R is the resistance. Since 0 A flows through the circuit, the voltage drop across the resistor is 0 V. However, the voltage of the top of the resistor relative to ground is 5V, which may be what's confusing you.
Additionally, it troubling to say something like "the voltage on the zener diode." When discussing voltage in regards to circuits, it typically means the voltage difference between two points. For instance, the voltage drop across a resistor means the voltage of one end of the resistor (relative to ground) minus the other end of the resistor (relative to ground). In this case, the voltage relative to ground on both ends of the resistor is 5V, the the voltage drop (5V - 5V) is equal to 0V. The zener diode - on the other hand - has one end connected directly to ground, so we know that end of the diode is at 0V (relative to ground since its grounded). Since the 5V hasn't dropped anywhere else in this series circuit, the entire 5V drop must be across the zener diode.
great video...
thank you....
😍
I can't believe i took a week to read a book when it all can be compressed in 11 minutes (or even 7m 20s with 1,5 speed)
Great discussion of zener diodes; I wonder in a processor chip whether these zener diodes and thermistors are the major elements?
Good, if the out put is connected to a transistor base pin with proper connection then it will become a voltage regulator transistor, and also zener diodes were used for starting of electronic devices by feather touch switches.,pre determined settings for any comparator's also zener diodes were used, and zener diodes were regulating the complete globe in smps power supply put.
When looking at these problems, are we looking at hole flow, or are we looking at electron flow? Basically, will the current flow through the resistor first, or will it flow through the diet first?
I think you can look at either flow and will still get the same answer. As long as you're consistent throughout your analysis and computation
I have a dumb question, if we have a circuit with two zener diodes and one resistor connected in series, both zener diodes are placed as reverse bias, if power source has voltage greater than one of the diode but smaller than the other diode, will there be no current flow in this circuit?
Thank you for a great video. You provided the explanation and formula for how one would calculate the current in the entire series circuit but how would you calculate the current in the diode versus the resistor?
Really appreciate......the examples are very useful and valuable.
like damn ... i couldnt understand my professor ... but this, makes it look easier
Q. what is breakdown voltage for reverse bias for normal diode?
Thank you for Simplifying this for me. I Liked and Subscribed!
This is an excellent tutorial.
First time watching one of your videos and really liked how simple your explanations are. I do have one question, what software do you use to make these?
Can you imagine the confusion that a young student would have after devouring and totally understanding your excellent tutorials on electrolytic and battery cells where it shows the current flowing INTO the cathode of the Battery (positive terminal), and then studying the electronic videos where it shows current flowing OUT OF the battery's positive terminal. We would explain it to the student as "oh, that's just conventional current". Conventional current he says ? What is that? What is flowing out of the positive terminal?" nothing is flowing out of the positive terminal son. " What do you mean nothing is flowing, why is it called a current if nothing is flowing
Believe it or not, the Navy is the only entity that shows current flowing correctly in a circuit.....
@@maskedmarvyl4774 fascinating
If you were using a mouse to draw these, then I have to say, what a pro!
He's using a digital drawing board, you can hear it.
U r great.....u saved my day 😎😎😎😎
Ive learned more than one or two thank u so very much
Nice explained!
sir, what happens if the input voltage is equal to 12v.,does the current flows or not.
I have car battery booster - input for charging the battery is 5v the battery in the booster is 12.9v what size would the zener be?
You must be an engineer I have always learned current flows from negative to positive!
what
Wtf
In theory current does flow from neg to pos. But since we didn't know that in the beginning engineers assumed it flowed from pos to neg and that's what practical electronics is based on. Confusing?? Yes...but so is the metric system and try studying transistor hole flow theory sometime. Some things just defy logic and theories quite often get disproved over time.
Hence his use of the phrase " *conventional* current", which does go from positive to negative, despite electrons moving the other way.
You think current flow is electrons, but electrons have _negative_ charge.
If I give you negative money , flow of money is from you to me. That's maths and physics.
So I'll tell you what, _you_ convince the _scientists_ to rewrite Physics with the charge on the electron being positive, and _then_ the engineers will follow suit. Deal?
Thanks a lot! That was pretty easy to learn this 👍🏻
Thank you so much for this.
Even when I think I know I always learn something. I see in schematics around the resistor placed after the zener diode, I believe this does not affect the behaviour of the diode, does it?
Thank you sir.
Sir pls what if the zener diode was in forward bias
Excellent tutorial.
Thank you
Thanks, your a absolute legend!
If I don't have access to an AC power source, would a signal generator suffice to produce the sine wave for input to test this circuit?
Your videos are very useful. Thanks
This is great and very understandable
is there also a diode liks this which regulates the voltage without dropping it by the regulated amount, for example if i have a 24v battery that goes to a zener diode and then to a solenoidvalve that needs 24v volts, is there some sort of diode that can only let the current through at 24v without taking 24 volts
Great tutorial video!
For a Zener Diode to be in Zener mode, the voltage source just needs to be higher than the Zener voltage? There are no other conditions?