What is an operational amplifier?

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The "operational amplifier" has two differential inputs and very high gain. Willy describes the symbol and properties of an op-amp. Op-amps are the backbone of analog circuit design.

[@EngineeringNibbles]

Even though you don't get many views, the people you do help are the motivated ones. Thank you

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This is true :)

[@willymcallister5852]

Thank you for your kind words. I'm continuing to work on this at spinningnumbers.org.

[@jrM5492]

4.2M subscriber is a lot of views.

[@cameronburton241]

@@jrM5492 they had a lot less 2 years ago when the comment was posted

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@@jrM5492 subscribers do not define view... im sure the total view is quite clear right there

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Those courses are literally saving my life every day in university

[@blingblingsam1490]

Wish I had that in my time in college lol

[@Yiannis2112]

Trendy bs. Nothing better than a good book. But you need to put the effort and time...you know...actually study...

[@wasneeplus]

Will they murder you if you don't pass your exams?

[@anirudhsreeram4015]

@@Yiannis2112 In what way is this video _not_ actual studies? 'Actual' isn't defined as 'the kind I like', you know.

[@Yiannis2112]

@@anirudhsreeram4015 So you believe you studied opamps by watching a 12 min video. Right?

[@Martin-dn9gr]

This is the most clear tutorial on op-amp I've ever seen

[@VERGIS92]

basically Op Amps were invented in WW2, because there was a big necessity to electronically direct anti anti-aircraft guns towards german planes, very fast, by the use of radar. The output of an op amp will always change, so as to make the two inputs equal, one input being the radar target, and the gun ends up locking on the target. the difference between the gun's position and the target's position was some kind of input voltage, and as one input tries to match the other, the gun moves and the target is locked, and the two inputs are equal again. it was a very tricky and clever invention that actually has some kind of basic artificial intelligence. After that they were used in navigation system analog computers and so much more, the whole purpose is to perform calculations, all kinds of mathematical calculations. the op amp improved anti airraft firing accuracy to 90%, and it was used in electroncially controlled machine guns, onboard heavy bombers in WW2

[@danieldewindt3919]

Thank you for the background knowledge! It is always nice to know why things where invented, to better understand the use.

[@Lunamana]

Thanks a lot, your explanation alone pretty much made me understand what an op-amp is :P

[@AM_JOSE]

If two inputs r equal then there wont b any gain..common mode...then how???

[@mikeboisvert5344]

@@Shubham-hk6yf lol, there's always gotta be the guy that discredits someone with no facts....

[@sujantkumarkv7277]

Thanks really for sharing.

[@DrHWO]

From dark art to Ah Haaaa. Excellent presentation from someone who clearly knows what he is talking about and how to put it across in simple terms. Thank you.

[@Flemagrimm]

This is nice. I've been waiting on some khan-style higher-level electronics stuff for a while. Thanks

[@clarenskybenoit5293]

Richard Grimm You ain't never lie, man.

[@ragnarlothbrok4827]

so what ive been struggling on in my lectures for a coupleweeks now is sorted by a couplevids lool extremely grateful for this

[@joeporsche1767]

I had watch many video about op-amp but non of them make me understand until I found your video. Your explanation is really clear. Thank a lot.

[@charleswest6372]

Ditto

[@jimisnotunique]

Great video, thanks! I plan to watch the rest of the series. I'm watching for remedial learning, for a graduate electronics course

[@1973jdmc]

you are BRILLIANT - trying to find a video that explains everything from the the beginning is soo hard. You do just that-

[@MrRadbadger]

Best basic Op Amp tute around. Do you want to understand what op amps do? Watch this video.

[@PhuckHue2]

opamp is a black triangle with legs

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PhuckHue2 are u Illuminati follower?? pyramid🌀🌀🌀(666)

[@eskindertsegaye3466]

sonic boom what about u ???

[@minhajshovon9789]

yeah why not

[@abcddd580]

beautifully explained. Khan Academy keeps all their videos to a high standard of quality, and clarity.

[@catherinedavis2431]

cathe,!!nn!!!!aar

[@mobyflyer7763]

Hey guy, you've made a very good video, because I'm german and the most videos I've shown, I don't understand it, by you're video I understand all! (thumb up :))

[@tsadarsh2403]

Thank you so much for putting the information is a easily understandable way. Khan Academy is always good in this.

[@Eduardo_Espinoza]

I can't believe I thought electrics were so easy in electronics intro; now my ADHD is getting the best of me. Yet, thank you so much Khan academy for teaching me how these buggers works!!!!!!!! :DDDDDDD

[@user-be4yc2vr5c]

Dude. Awesome Explanin'. Thank you for your service to the public comrade.

[@haziehigh3694]

Thank you sooo much this video helps a lot and ur literally saving my Al exams ..thanku thanku thanku

[@anujadassanayake5732]

Physics exam is tomorrow and I'm watching this today! It helps!

[@lensvision9762]

if someone is thinking this video is not complete, visit the Khan Academy website and search for this topic and you will get a series of videos

[@OlumideAyeni]

I have watched a couple of videos on this topic, and I wish I saw yours earlier. Thank you!

[@CH-tv1cy]

Best tutorials on KZbin.

[@min2MAXdances]

This tutorial is so helpful

[@kabandajamilu9036]

So nice and clear what great teacher from said kabanda

[@thearabianwolf3996]

Perfect explanation from perfect channel I advise every electrical engineers to subscribe this channel Easier than studying in high schools with sort of boring teachers I hope you always put a link if someone wanna download the videos Thank you sir

[@serpent035]

Loved the video, great explanation. With good and clear use of language. But in the end you say something about a trick and how to look at a symbol but you don't really say what the difference is between the symbols.

[@ruzainiahmedh3521]

when the diffrential input is increased negatively,it acts like and inverting input nah? So saturation value should be a positive value (since it gets inverted) but why graph is not as i said?

[@muneebtahir9822]

7:40 shouldn't the inverting input be connected with postive source and non inverting with the negative?

[@paulfrischknecht3999]

Correct me if I am wrong: There is no such thing as a "single ended input" or "non-differential" input, at least when we talk about voltage (difference) inputs. A voltage can only ever be measured in relation to another voltage. Therefore all voltage inputs (e.g. digital inputs) of electronic components are differential inputs. It it just by convention and to reduce pin count that we usually measure all voltages against a common "ground" voltage, so that chips with n digital inputs don't need 2n inputs...

[@willymcallister5852]

Yes, all voltage measurements require you to probe two points in the circuit. The term "differential" usually means the signal of interest is carried on two wires, a + version and a - version. If one wire goes up, the other goes down. This has the nice effect of doubling the voltage change. (If v+ goes from 0 to 1, and v- goes from 0 to -1, the total difference is 2V.) If you have a differential amplifier and you connect one input to ground you have defeated one of the advantages of the differential design. You would say you are using a "double-ended" amplifier in a "single-ended" application. ([e-mail])

[@ahoorapersia4698]

God bless you sir. Tnx a lot.

[@atrogpx]

Well-explained. Thank you.

[@minartistree]

In class I was thinking "Where is the extra energy to increase the voltage coming from!?" - finally answered.

[@GryffieTube]

Great video thank you very much indeed EXCEPT I am very sorry, unless I am mistaken, there is NO separate ground pin on an actual op amp chip. My understanding is that there are typically eight pins on the chip as follows: 1. Offset Null 2. Inverting input (v+) 3. Non-inverting input (v-) 4. Power -V 5. Offset Null 6. Output 7. Power +V 8. NC Please explain which one of these is the "ground pin" you refer to at 6:54? Thanks.

[@peatmoss4415]

#4 obviously

[@dylanwillms1275]

you are explaining it so good im a 13 years old and i can understand it liked the vid and subscribed

[@MysteryofScience]

Dylan Willms now u r 14

[@jomango1929]

Continue your journey !

[@markmanon5543]

Dylan Willms now you’re 15

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now you are 15+(2/12)

[@ClaudiaSt56]

Somebody happens to know which amplification I get by using rosenstark method? Open or closed loop? That would be really nice :)

[@SteveGergetz]

That was really a fabulous explanation that helped me understand op amps better than most of my previous instruction. Thank you! Although I have to point out that you made it more convoluted than necessary when talking about the inverted input signals. It was already self-explanatory saying that the output is proportional to the differential between the two inputs. If the lower input goes up, then naturally there is a smaller difference between the inputs and there will be a smaller output. Also I don't understand why you mentioned the flipped symbol we might see on a drawing. I mean so what is the significance if we do see that symbol? What are we supposed to ascertain from that? Does it have a specific meaning when its flipped? Thanks!

[@eugenenault4935]

The best explanation. Thanks

[@arpitaroy3119]

Sir please make videoes on r to r ladder and dual slope integrator

[@wikelightchika9441]

Pls how do I get a playlist on basic electronic in your channel. Because I can't find it I saw thousand of list

[@danstark462]

you are very clear to understand.

[@jimadams2473]

Excellent video on OP Amps!!! Thanks

[@zamp7927]

what is inside that triangular shape is important ! but no one shows the internal design of it

[@willymcallister5852]

The design of opamps is one of the most advanced and sophisticated analog designs there is. Companies go out of their way to not reveal the innards of their chips, going so far as to add fake structures to fool their competitors. You can find "representational" schematics of early opamps like the uA741.

[@benjaminn412]

Hi, why are we learning about op-amp in electronic engineering? whats its purpose?

[@swansoony]

Nice well done right from the beginning I subscribed Thank you

[@md.imranhossain8449]

why input current is zero for ideal op-amp? why input resistance is infinity?

[@willymcallister5852]

Zero input current is a goal when you design an opamp. You will why this is a very useful property when you view the videos on inverting and non-inverting opamp circuits. In real life, it is not possible to achieve 0 input current, but they come remarkably close to the ideal.

[@MahiAbrarAmer]

7:40 what if we didn't ground the circuit? what would have happened? No +12V on top and no -12V on the bottom?

[@whoisdanielsong]

This video was so insightful! Incredible!

[@ibtihajmujahid8206]

Hy.Sir, I wanna ask that is the positive power supply always connecred to the non-inverting terminal or it can be the opposite.Just wanna know the power supplying in a little more detail

[@lukagolob4755]

i have one correction the current that goes into the op-amp isnt 0 cause if u multiply that by resistivity of the op-amp u get zero. The op-amps resistivty is very high u can say 1 000 000 ohms so the current is close to zero at 1 micro amper or even less ifu say that the resistivity is for example one million--> thats why there almost 0 current there...

[@agstechnicalsupport]

A perfect introduction into Opamps. Thank you.

[@yoosn911]

very clear explanation

[@zeproo]

A+++ explanation.

[@enewhuis]

Nice intro. How do real op amps differ from this ideal linear relationship? And does the frequency of the input signal alter non-linear effects? Are these unpleasantries amplified (pun intended) at saturation?

[@nedko]

Guys, where is the next part?

[@alterator]

The best explaination

[@kaus05]

I didn't quite got what specifically up/down is ? Their voltage?

[@ptyxs]

Enlightening. Thank you so much.

[@radostar7139]

power 12 dcV is shown. Why higher /lower input signal ?and output not shown?

[@AiKhampang]

thank you

[@umarmukhtar731]

Finally I understand. Great video, thank you

[@SayanGHD]

Thank you Sal ! You're the best !

[@SuperSaltyFries]

that's actually not Sal, I can't remember his name but another guy teaches these lessons.

[@user-li6pn1jb7f]

thanks for d crystal clear explanation breeew

[@MrBurninCross]

It verges on the physically impossible??? (Something has to be lost in lieu of gain, i.e., losses?)

[@DepthlessArtist]

Why is Bill Murray talking about op-amps?

[@fardellp]

Might be a smaller signal out! (i.e. a negative out with positive input)

[@robstorms]

there is in general no ground connection or node(as stated in the video) on an op amp. i am surprised at this rather fundamental error

[@rajsekharsharma8199]

what can be the inputs(inverting or non-inverting) and what does +ve and -ve input suggest?

[@shafeckbrown496]

Marvelous . Thanks very much

[@brandonornelas4393]

what does "and v out can go both positive and negative around ground" mean

[@willymcallister5852]

If the power supply pins are connected to, for example, +12V and -12V then the output of the opamp can swing (close to) those values, perhaps +11.5V to -11.5V. This is the same as saying, "v_out can swing above and below ground".

[@user-ye9kx9to2w]

Nice video

[@ebenezerkassu87]

can any one suggest me anyother good channels plsss

[@arrmeilajeyanathan7318]

What do you mean by V- goes up and Vo goes down??

[@dawsonzinza1671]

When I first heard your voice I thought you were Brian Wampler, but with a low pass filter.

[@AA-qe9hm]

How is it different from a transistor?

[@thomascassidy2724]

I've never seen an op-amp with both a negative supply pin AND a ground pin - any examples?

[@willymcallister5852]

I showed too many pins. Should have omitted the ground pin. Opamps have only two power pins, connected to either +/- V, o,r gnd and +V.

[@kishankankhara1998]

nice videos you upload man thanks a lot for the help....keep up the good work..again tysm

[@g00glian0]

If this is for beginners, it is pretty advanced. I still can't still ya what it is used for, but thanks anyway.

[@saadatshahidi]

very helpful

[@Lucho24cr]

Great video! Do anyone knows what kind of tactile board or panel is used in tutorials like this one??? I'm a teacher and i would like to teach this way.

[@willymcallister5852]

The tablet I use is an ordinary Wacom Bamboo. Any USB tablet will do. It's a good idea to buy a good USB microphone. This video was recorded with a Samson. Screen and audio are captured and edited in Camtasia. The drawing program is Autodesk Sketchbook, pro version.

[@Lucho24cr]

@@willymcallister5852 thanks!

[@englishrupe01]

@@willymcallister5852 Cool......thanks Willy! And Autodesk has just made their Autodesk Sketchbook free.....including all the pro version elements! Nice!

[@stephaneroberts7545]

THANKS MAN!

[@adwoakb8694]

Thank you!!!! this video helped so much

[@moneerkutt1228]

nice!! you're amazing thank you

[@shivamkalia2010]

Its not full.. i could not find the rest

[@diegooyon7980]

Great stuff. You never mentioned what the difference was between the op amp diagram that has the inverting symbol at the top vs the one that has it at the bottom though. I guess we will never know =/

[@milesemanuelpaavola7994]

Thank you for sharing. :-D IT helps.

[@Vaeuca]

thank u a 10^999999

[@charleswolfe6849]

This guy sounds like Norm McDonald

[@Akshay-cj3hq]

wait.. where is Sal? I like his voice :(

[@pabloescobar2089]

Akshay Sapra same bruh

[@willymcallister5852]

I like Sal's voice, too. It would be great if Sal could do every video. I know a little bit more than he does about this kind of opamp circuit, so Sal asked me to make these videos.

[@Amigaudio]

Is this Dave Weckls voice?

[@penelopeannetsiblakis9415]

AWESOME THANK YOU!!!!

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Hi, we think we have chance to work together. Our capacitor can make your amplifier work well.

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May I turn my F into an A by watching this video.

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God bless you :)

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May the Easter Bunny bring you many hard boiled eggs for your feast this equinox.

[@SarthakSR]

legends are watching this in 2021

[@ConsertandoTudo]

I want to know who is talking in this video because I know that voice.

[@charlieleetboss9513]

You sound like Norm Mcdonald

[@allencao4579]

goat

[@serdashehu]

isnt it V+ = V- therefore V+ - V- =0 ??

[@shubhamjoshi6839]

here v+ and v- are denoted to show the inputs its not positive or negative voltage

[@RoseMyLast]

Hey could you try this software? Any feedback is appreciated! Search: 'Circuit Solver' on Google Play.

[@dpyp]

John Smith yess

[@ogolster8346]

stfu Mr. Multiple accounts

[@willymcallister5852]

I also invite you to try out this circuit simulator: spinningnumbers.org/a/circuit-sandbox.html No installation required, works in any browser.

[@animeshsah5843]

*OPIAM*

[@eliebakkar5944]

fuckin amazing bro good job