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  • Published on Apr 4, 2014
  • The most often requested video! In this tutorial Dave explains what Operational Amplifiers (OpAmps) are and how they work. The concepts of negative feedback, open loop gain, virtual grounds and opamp action. The comparator, the buffer, the inverting and non-inverting amplifiers, the differential amplifier, and the integrator circuit configurations are also explained.
    Then a practical breadboard circuit to demonstrate a virtual ground and the effect of voltage rail limitations.
    All EEVblog Opamp related videos are here:
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Comments • 2 081

  • Regal_7
    Regal_7 2 years ago +499

    I know this will probably get lost in the comments but I have to say it. I absolutely have a high respect for people like you who share knowledge so freely and willingly. People like you are a godsend. Thank you sincerely.

  • Mark Jay
    Mark Jay 4 years ago +622

    "The gain is almost infinite"
    spoken like a true engineer!

    • SOME CAN'T
      SOME CAN'T 24 days ago

      @TheXvid Google he's showing crossover distortion.

    •  Illustratio Spectrum Studio Light (ISSL)
      Illustratio Spectrum Studio Light (ISSL) 2 months ago

      This guy is DATA from Startrek ];-D.

    • Neil Albaugh
      Neil Albaugh 3 months ago

      @Robert Kokal Stay away from your keyboard if you've been drinking.

    • protektwar
      protektwar 3 months ago

      Almost infinite is infinite + something which is infinite :)

    • Neil Albaugh
      Neil Albaugh 3 months ago

      @TheXvid Google An op amp delivers current into a load connected to its output but also into its feedback resistor. With no load, the only current from its output pin is into the feedback resistor. Changing from a 100k feedback resistor to a 10K draws more current from the output. With the + input at ground, the - input also looks like ground, so the current through the FB resistor is Vout / Rfb.

  • Mikael Mørup
    Mikael Mørup 2 years ago +194

    Six years later, this is still the best and most understandable intro to Op Amps ever.

    • bosborn1
      bosborn1 Month ago

      Had to watch this video to make sense of my class lecture on op amps. Funny that I have to watch a free video to make sense of a paid class

    •  Illustratio Spectrum Studio Light (ISSL)
      Illustratio Spectrum Studio Light (ISSL) 2 months ago

      This guy is DATA from Startrek ];-D.

    • Goran Vuletic
      Goran Vuletic 4 months ago +1

      One reason that I have never excelled in school is because most of my teachers were the oposite of this guy, their lectures were dull and incomplete.

    • Kimo Troph
      Kimo Troph 4 months ago +1

      That's for sure. I wish I had professor like him.

    • The One True Anthony Long
      The One True Anthony Long 7 months ago +3

      This is the first instance where a lecturer explains that op amps should'nt be treated as the same amplifiers theyre made of and that broke the wall id been stuck behind. Catching up on homework as I watch. Wish me luck.

  • tim oliver
    tim oliver 5 years ago +66

    Hi dave I've been watching your channel a lot for the last couple years now and it's fantastic! I'm currently doing my honors in electronics engineering and my University here in hamilton New Zealand has instructed my class to watch this video on the current section we are covering on op-amps. You have finally made it to university level teaching my friend!

    • Youtube Google
      Youtube Google Year ago

      48:40
      Can anybody please tell me the reason of this ?

  • Neil Albaugh
    Neil Albaugh Year ago +42

    As a retired Senior Applications Engineer at Burr-Brown and Texas Instruments, I must compliment you on this presentation! It is very similar to the "factory" technical presentations that we used to give to audiences around the globe. The technical level is just right, not to basic and not too advanced. Good job! To be a good teacher it takes far more than just knowledge of the subject. A teacher's job is to impart knowledge to his student; if the student doesn't understand, the teacher is not doing his job. Some PhDs can teach, others can't- Richard Feynman was an example of a fellow who not only thoroughly understood his subject but who could teach it as well.... and do it in an interesting and entertaining manner.

    • Neil Albaugh
      Neil Albaugh 3 months ago

      @Naveen Gupta The best way is to send in a copy of your resume. Good luck- the world needs more analog engineers.

    • Naveen Gupta
      Naveen Gupta 3 months ago

      How i can get a job in TI ?😅😅😅i mean its awkward to ask this way but yeah
      Sorry beforehand 😅😅

  • Mike Lamay
    Mike Lamay Year ago +15

    The fact we can learn this and not have to go into debt... your a gift to engineering Dave!

  • soupisgdfood
    soupisgdfood 3 years ago +6

    Dave, this is amazing. Thank you for these mini classes, honestly it’s worth more than any electronics class I ever paid for.
    Negative feedback op-amps just clicked into place for me about 10 minutes in. I had been struggling with this concept for days. Thank you so much.

  • Jaguar paw
    Jaguar paw 3 years ago +396

    this video got me my first electronic job i watched this video before my interview and they quizzed me on op amps! the luck!

    • Sahan Chinthaka
      Sahan Chinthaka 12 days ago

    • xxBrainwashedxx
      xxBrainwashedxx Month ago +1

      @TheXvid Google I'm curious of the answer as well. Care to share?

    • Tony Shark
      Tony Shark 2 months ago

      congratulationsssssssss

    • Youtube Google
      Youtube Google 11 months ago

      @Sub Critical
      I was not asking for the uses of opamp,
      I was asking the answer to the video question at 48:40
      But, I already got it.
      And thanks for your concern 😊

    • Sub Critical
      Sub Critical 11 months ago +1

      @TheXvid GoogleThey are utilized in guitar amplifiers and guitar pedals to create great tones. Think Eddie Van Halen (RIP). This just one instance of their usage. Another application is used in cruise control within vehicles. There are thousands of applications for Op Amps.

  • Keith Minchin
    Keith Minchin 8 days ago

    I find myself revisiting this tutorial as a refresher every time I need to incorporate an OpAmp into one of my projects. Thanks Dave! 👍🏻

  • Dan Charlton
    Dan Charlton Year ago +4

    7 years on and your videos are still helping new technicians. I really appreciate this, thank you.

  • Unfortunate Observer
    Unfortunate Observer 3 years ago +3

    It's so great to see fellow Australians showing up on TheXvid. Especially for something like explaining electricity. Bringing fame and reputation to our country!

  • FatElvis
    FatElvis 5 years ago +4

    You are really great at this. I'm in a 3rd semester EET student and I learned a thing or two about op-amps from you. I should be paying you tuition!

  • funkyironman69
    funkyironman69 7 years ago +220

    If anyone is interested the gain of the non-inverting config can be derived from the voltage divider equation:
    Vin = Vout*R1/(R1+Rf)
    Vin/Vout = R1/(R1+Rf)
    Vout/Vin = (R1+Rf)/R1
    Vout/Vin = 1+Rf/R1
    And the gain of the inverting config can be found from the currents:
    I(Rf) = Vout/Rf
    I(R1) = -Vin/R1
    -> Current through both resistors is equal so...
    -Vin/R1 = Vout/Rf
    Vout/Vin = -Rf/R1
    :)

    • thimaya panda
      thimaya panda Year ago +1

      Here Vin1=Vin2 due to the virtual short between the input terminals, if anyone had a doubt

    • cjay2
      cjay2 2 years ago +1

      Amazing how simple the above is when you can assume that the internal gain of the opamp is infinite. Everyone going through EE should be able to demonstrate the above in the time it takes to write it down. Well done.

    • Yo ming
      Yo ming 4 years ago +3

      great job thank you

  • speedsterh
    speedsterh 2 years ago +3

    If only I had the opportunity to watch this when I was learning about OpAmps some decades ago ! So much simpler to understand with you, Dave !

  • barry
    barry 3 years ago +1

    Even after 30 years away from electronics I got the gist of you lesson, thanks you explain it very well and in manner I just love. I worked in the dept of Navy as a trainee and we had two parts, one was a TAFE course the other was direct from Naval lecturers. The naval lecturers were like you extremely conversant and able to explain in a much more understandable manner.

  • Joe Williams
    Joe Williams 5 years ago

    You are the worlds best electronics teacher! I have watched all of the EEVblog's and I enjoy watching everyone of them!
    Thanks Dave!

  • Bill Hentig
    Bill Hentig 20 days ago

    I am in my senior year for EE and we had a whole 8 weeks in one of my circuit theory classes dedicated solely to op amps. We got to delve deep into these and do some really fun design problems and lab experiments. This video really is a great refresher and good start for anyone new to them.

  • Tarek Aglan
    Tarek Aglan 7 years ago +137

    Regarding the puzzle at the end, the low resistance effect is an increased current at the OA output. the OA at approximately Vout= -0.5V should sink 50uA which is higher than the value in the datasheet/figure13 of 30uA max. so the virtual ground voltage fluctuates and so does the output at approx. -0.5V.

    • hereiam2005
      hereiam2005 10 months ago

      @Cire Ekratz
      Not sure what you meant.
      If you check the vast majority of figures (including fig. 7-47 in the new datasheet), the op-amp were being powered by single rail as oppose to dual rails as in Dave's case.
      A dead giveaway is the fact that in fig 7-47, maximum output voltage for Vs=5V is ~ 4v, not possible if Vs is actually split into +-2.5V.
      Since it is single rail, all voltages must be between V+ and ground. The op amp can't produce any negative voltage since it is powered by a single positive rail.
      In said figures, they measured the near-rail swing capability of the op amp, and it is quite natural that the capability of the op-amp is drastically lowered when forced to swing near its power rails.
      You can also check figure 11 in the datasheet for the LM358-N, which should look very similar. There they drew the schematic for their measurement/figure, and it showed that they explicitly used single supply rail, hence the near-rail limited current characteristic, which is quite common in op-amps.
      In Dave's case however, the weird behavior happens very close to split rail ground, or ~0 when the signal is +-10V. As such the behavior is not due to the op amp's near rail characteristics.

    • True Forum
      True Forum Year ago

      great job Tarek! abbas

    • Youtube Google
      Youtube Google Year ago

      @Cire Ekratz .

    • Cire Ekratz
      Cire Ekratz Year ago +3

      @TheXvid Google you are right. i slipped a line in the diagram :)

    • Youtube Google
      Youtube Google Year ago +4

      @Cire Ekratz
      Yeah,
      Thanks for clarifying 😁
      You cleared all my Doubts.
      ( I have just 1 correction on your last comment, it is capable of sinking max 40 mA, and stable till approx 35 mA (not 25 mA) )

  • Tom Lyon
    Tom Lyon 4 years ago +1

    Took years to comprehend this stuff. Especially when it came to more complex circuitry and control of DC motors from controlling speed, current, volts, positioning, etc. Great video and spot on! Thanks

  • philstuf
    philstuf 4 years ago +2

    Love these. More, please. I've been using Op Amps and Comparators for decades and still learned a couple tricks watching this video!

  • Iam D
    Iam D 11 months ago +3

    Been a tech for 43 years and I have never seen it explained so concise. Thanks and I am turning the junior techs onto this video. Cheers!

  • Daniel Armstrong
    Daniel Armstrong 3 months ago +2

    Great teaching skills. Good job, very informative and easy to follow. Reminds me over 20 years ago my electronics teacher back at modesto high school in California, i did alot of VICA skills challenges it was fun and i use that information to this day

  • Mirko Mueller
    Mirko Mueller 6 years ago +222

    what makes you a gorgeous teacher is that you not only talk about what is going on but also about what the follower might think is going on but actually is not and why. i had so many frustrating experiences in the past because of teachers that did'nt care about that. i truly love your lessons.

    • Youtube Google
      Youtube Google Year ago +1

      48:40
      Can anybody please tell me the reason of this ?

    • kent huang
      kent huang 3 years ago +2

      A good teacher.

    • Rýán Túçk
      Rýán Túçk 4 years ago +2

      Mirko Mueller So are you enthralled?

    • LazyH-Online
      LazyH-Online 4 years ago +5

      Mirko Mueller it's also great to see someone enthusiastic about what he does.

  • gskempe9
    gskempe9 3 years ago +1

    When I learned how to use Op-Amps, the 741 was the state of the art at the time. Yes, had to learn them the hard way back in those days. What a great refresher course for this young man born 9-11-1946. Great job Dave and thank you. Respectfully, Steve

  • Zygfryd Homonto
    Zygfryd Homonto Year ago +1

    I spent few years in school to learn this (hundreds of years ago) but no teacher was able to present it so clearly like you did - thank you bro

  • Alexander Severniy
    Alexander Severniy 4 years ago +1

    Thanks for this video. Now I recommend it as the intro to OpAmp use in beginners electronics. Interesting to note that some students do not use transistors at all. it is easy for them to use dual OpAmp chips rather than use several transistor stages =)) They do not even know how transistors work in signal amplify mode!

  • Rasmus Øgendahl Hochreuter

    This is my new favorite TheXvid channel!!! I am a marine engineer by trade, but I started getting bored, so I signed up for an online electronic engineering programme at my local university, to put my spare time into good use.
    I have never gained much from sitting in a classroom listening to a lecturer bleating for two hours at a blackboard, so I was thrilled, when I got the opportunity to work at getting a degree, working by myself at home. These videos are an absolutely excellent supplement to all the videos available from my university.
    Thank you!!!

  • kevin jad
    kevin jad 2 years ago +232

    In my whole electronics major shit , I have never seen a person who explains virtual ground like this.
    #RESPECT

    • Name Redacted
      Name Redacted Year ago

      Try being taught by an engineer, like Dave is. When they have academics teaching you, you won't ever hear anything practical to the job.

    • Michele Galliano
      Michele Galliano Year ago +1

      i think it is better to talk about virtual short circuit

    • B. D
      B. D Year ago +1

      @Steve well, you're correct but he named it virtual ground (fake) just to make it simple to understand that it will have no voltage at that particular point, and mostly ground has 0 volts if you leave aside complicated electrochemistry.

    • Steve
      Steve Year ago

      Marc Victor I suggest you some reading on electromagnetism with a couple exercises. The book I studied the most from is H. Benson, physics 2, Electromagnetism

    • Marc Victor
      Marc Victor Year ago

      @Steve Nvm I searched for it

  • patrolmaverick
    patrolmaverick 4 years ago +1

    Great video. For an electronics novice I learned more than I was expecting.
    Subscribed.

  • Skinny R&D
    Skinny R&D Year ago +5

    Thank you Dave! This video has saved me headaches on multiple occasions. Everything is so well explained. I keep coming back to it for reference.

  • Umer Khayyam
    Umer Khayyam Year ago +1

    You are a life saver. I hope you did more videos like this.
    I am glad to have benefitted from your knowledge.

  • angturil
    angturil Year ago

    This is probably the most comprehensive and effective explanation I've ever watched about opamps. You sir are a pedagogical genius!

  • Samarpit Sahoo
    Samarpit Sahoo 3 years ago +5

    Well, I secured more marks than my friends in our exam just by watching this video 2 hour prior to my exam. Thanks Dave.

  • IronEagle585
    IronEagle585 Month ago

    Brilliant, learnt more in 20 mins that I did in a year of full time study, thanks for all your great videos! ;)

  • Pedro Herrera
    Pedro Herrera 4 months ago

    wish I found this when I took circuit theory, you make it so much more fun than my professor does

  • Flash001USA
    Flash001USA 7 years ago +59

    Very helpful. I'm an electronics technician and you see this stuff when you're doing repairs or troubleshooting but you never get down to the nitty gritty details especially after 30+ or so years goes by from your initial electronics training so it was really nice of you to explain this especially on layman's terms. Someone else mentioned in this blog about cutting and pasting working circuits into projects and calculating as you went along to fit your needs which is pretty much what I've done in the past so this has really been a BIG help in the memory refresh department. Thank you ten times over and may the "electro" Gods shine good fortune down upon you sir!

    • dilipand
      dilipand 2 years ago

      electronic technicians nowdays repair FLAT TVs, monitors, cell phones, install and repair satellite installations, alarm systems, fire detection systems, CCTV installation, PLC programming and maintenance in industrial applications, and a variety of other applications ...
      Nowadays, even the electrical appliances of a hotel kitchen may have electronic control boards with fiber optic and internet connectivity.
      And in some countries it is not always "throw the old board away and put the new one"
      this is the easy way that even a 10 yo child can do.
      What if a new electronic board is too expensive ?

    • Catalin
      Catalin 7 years ago +1

      I had electronics like a hobby in the secondary school and also the time I was in the university even I've studied mechanics. Great presentation !!

  • Gonzalo Aguilar Delgado
    Gonzalo Aguilar Delgado 3 years ago +1

    Just great, a topic I always left apart until you discover it to me. I suppose there are LOTS of applications but it's great to learn that way. A lot of things I discovered! Thank you so much!

  • Geev Nahal
    Geev Nahal 4 years ago +1

    This was great! At the same time I was learning how to make a CPU from Ben Eater channel. It occur to me that it would be awesome if someone start an RF project and explain main RF concepts along the way when it is needed, as Ben did. Thank you again

  • Euphoric Monkey
    Euphoric Monkey Year ago

    Your videos are simply outstanding. I love learning about things and messing with electronics is one of my hobbies. Thanks for taking the time to make this and all your other videos.

  • Umbra Jord
    Umbra Jord 3 years ago +19

    FINALLY!!!! A video that ACTUALLY EXPLAINS HOW IT WORKS!!!!!
    Dave, this video was a godsend.

  • Andypro
    Andypro 8 years ago +5

    Thanks for doing teaching vids, Dave! I took many electrical engineering courses in college and we did a lot with op-amps, but I'm embarrassed to admit I've completely forgotten everything about them since then. These practical introduction videos are perfect for people like me who want to reconnect to something we learned in the past. Thanks again!

  • Aidan
    Aidan Year ago +1

    I finally understand these, I was struggling in my lectures because my professor just couldn't explain them. Thank you so much!!!

  • Nate Sweet
    Nate Sweet 5 months ago

    This was amazing, thank you! I'm just a hobbyist but I got all of what you presented. It's the first of your videos I've seen. Now I have a looot of watching to do!

  • Sunshine
    Sunshine 5 years ago

    Great lesson! Clear and to the point! Thank you.

  • Vera Gerginn
    Vera Gerginn 7 months ago

    Great tutorial. Easy to understand, esp. from a perspective of understanding what's going on if one sees an electronic drawing and knows what's going on there.

  • Chester Pertchik
    Chester Pertchik 5 years ago

    I enjoy benefiting from all of your videos, but this one has given me confidence to breadboard and experiment with these circuits. Much thanks for that!

  • BladeforgerKLX
    BladeforgerKLX 5 years ago +1

    Great job with the explanations!!! Very detailed, Dave, and I'll be watching it again. THANK YOU!!

  • Rishikesh
    Rishikesh 4 years ago +1

    great video! please keep making more tutorials like this :)

  • A V
    A V Year ago

    Brilliant! No one can explain it better. Thank you so much for the lesson

  • Zdeněk Bezdíček
    Zdeněk Bezdíček 3 years ago

    So simple explained and understandable. Helped me a ton at measuring practice class. Thank you so much.

  • Phantom
    Phantom 5 months ago

    I was having a really hard time understanding opamps. Thank you for making my life easier!!

  • Andrew Lord
    Andrew Lord 2 years ago

    Great video Dave, thanks for all of the work you do!

  • Matthew Luttrell
    Matthew Luttrell Year ago

    You are single handedly getting me through my digital electronics class!!

  • TreasureToTrash
    TreasureToTrash Year ago

    Best explanation on ALL of youtube. This was incredibly helpful. You have earned my subscription!

  • basilkumi basile
    basilkumi basile 5 years ago +1

    Hello sir and thank you for your very informative videos.
    I have a question for you: I would like to make a circuit that can give me a rectangular signal between 0V and 5 V. A kind of switch, but with a smaller rise time in the order of 50ns to 100ns.
    I tried with the Mosfets, but the output siganl to a lot of swings and noises.
    What you can advise me or have already made a circuit like that.
    I like to test the filters placed at the retraction of a microcontroller by placing this signal recregular and read the response of the filter.
    Thank you

  • Gergő Sütő
    Gergő Sütő 5 years ago

    Thanks to this video I got 97% to my circuit's homework!! :D Thanks a lot, you are a great teacher :)

  • Snarky Mark
    Snarky Mark 2 years ago

    Thanks a lot for this vid, Dave. I'm in Basic Circuits now, and your explication is notably better than most others.

  • TheElectr0nicus
    TheElectr0nicus 8 years ago +19

    Excellent video Dave!
    Concerning the puzzle on the end. I think it's the reduced current sinking capabilities of the LM358 when Vout is small in respect to ground. If look up the "Output Characteristics Current Sinking" graph in the datasheet you can see that the LM358 can sink very little current at low output voltages. As you have a 1k R1 and 2Vpp input voltage you have 2mApp of current, which is still too much to sink for the LM358 at low output voltages. So the LM358 can't keep the virtual ground equal with the "real" ground trough it's FB network. Therefore you get those spikes and the sagging and rising of the virtual ground in between.

    • foobargorch
      foobargorch 6 years ago +1

      +TheElectr0nicus but why does it jump like that? And why is there such a weird knee in the sink around that voltage (i.e. the physical reason for the fact that it goes closer to linear at even lower voltages)

    • Tarek Aglan
      Tarek Aglan 7 years ago +1

      You are right, just a small clarification. the OA at Vout= -0.5V should sink 50uA which is higher than the value in the datasheet/figure13 of 30uA max. so the virtual ground voltage fluctuates and so does the output at approx. -0.5V.

    • TubiCal
      TubiCal 8 years ago +1

      That´s it, exatcly :)

    • gamingSlasher
      gamingSlasher 8 years ago

      Nice work! I noticed that all datasheets doesnt show this. The Motorola version did not so that might be an extra "trap for young players"

  • Mr. CroTech
    Mr. CroTech 7 months ago

    Thanks to you, and your videos I am today a successful engineer working in semiconductor industry. I am just coming back, years after I watched this video for the first time. I was having problems passing the only one remaining subject to get my degree and was searching for a helpful video on opamps. Not only you helped me, but also inspired me with your positive personality! Keep up the good work!

  • diego ruffilli
    diego ruffilli 2 years ago

    Majestic explanation. I'm always amazed how things can become clear after your videos. Unbelievable.

  • Anantha Krishnan Vilsan
    Anantha Krishnan Vilsan 10 months ago

    You helped me realize things in a practical way. Thank you very much. If possible kindly explain the ADC and DAC operation in depth please.

  • Фёдор Лендин

    Most valuable video ever! Thank you, Dave! Respect for your hobby (work)!!!

  • Opal Preston Shirley
    Opal Preston Shirley 6 years ago +6

    Excellent discussion. Takes me back 35 years to my intro to op-amps. My professor explained what was to us an amazing and confusion subject just as you did and within a day or so we couldn't wait for the lab. I'm now hooked on your channel. atb Opal

  • Adriaan Hattingh
    Adriaan Hattingh Month ago

    Thanks for such a clear explanation regarding OpAmps! It's a component I see on a lot of schematics and in a lot of other TheXvid videos, but I cannot see how and why it's included.

  • Jim E
    Jim E 2 years ago

    I am deeply grateful for your wonderfully simple explanation of OpAmps.
    I love your enthusiasm and ability to "dumb it down". it's obvious you LOVE your subject! If only every teacher was as good as you! THANK YOU FOR YOUR EFFORT Dave, and I LOVE your tee-shirt! :-).

  • Jonathan Vaucher
    Jonathan Vaucher Year ago

    Thank you for this very educational video!
    Are op-amps a good way to make the meter of an analog instrument more sensitive to signal ??
    If yes, have a very specific situation where I'd like to apply an op-amp:
    I have installed a shunted ammeter in my car to monitor how my alternator charges the battery, or when the battery is being discharged by various loads when the engine is off. The ammeter gauge reads up to 150A (scale goes from -150A to +150A) and is mounted on the dash. The ammeter shunt (150A 50mV) is external, being mounted behind the firewall. Two fused sense leads go from the shunt, through the firewall, to the dash ammeter gauge. It works well and I chosed a 150A ammeter because the alternator is rated 91A (at 5100rpm) and I know it's better not to use shunt to current more than 2/3 their ratings because they could get hot and possibly loose their calibration. But in normal situations, I never see more than + 20-35A right after I start the car (alternator charging battery), and after a few minutes the needle is close to 5-10 Amps (battery almost completely replenished by the alternator, not taking much charge anymore). So the thing is that each graduation on the ammeter gauge are 30A (not very precise). I'd like to be able to press a momentary switch (mounted on the dash) to increase the sensitivity of the ammeter gauge by a factor x5 (meaning when the current is 30A, the meter could display 150A). The shunt is rated for a 50mV voltage drop through the sense leads when the current is 150A. So at 30A, the voltage drop is 10mV. So basically, I'm looking for a small circuit (op-amp based?) that would linearly increase a 0-50mV signal to a 0-250mV one. I'm okay with 5-10% reading accuracy. I thought maybe I could find some suitable amplification circuit on amazon to do this job. Can you recommend anything ? I found something called a "AD620 Gain Signal Amplification Module", but I'm not sure if this is adequate. Any recommendation ?
    I do not want to install a smaller shunt instead of the 150A one. There was one instance in the past where the ammeter read close to 80A (I had jump started my car but my battery was completely dead at 0V). So I don't want to risk using a 30 or 50A shunt.

  • Steven Wallace
    Steven Wallace 3 years ago

    Wow - this is gold.... thanks for your time, very good explanation and very very useful! And here was me thinking op amps just amplify signals.... how wrong was I?!

  • Marc Robitaille
    Marc Robitaille 2 years ago +1

    Thanks for taking the time to do this... I'm learning electronics on my own and this really helps...

  • DrDudley Dragon
    DrDudley Dragon 3 years ago

    way to go buddy! I pay 3 grand in course fees a semester and you just explained it better then my professor could in 8 weeks so far. THANKS! keep at it.

  • xot
    xot Year ago

    Great video. I've been reading about Op Amps all day and not fully getting it. This crystallized everything I've read into something I can understand. Thanks!

  • Siddharth Choudhary
    Siddharth Choudhary 4 years ago

    Great video. Would love to let you know that MANY people like myself appreciate and love your content! Keep rocking!

  • 998SBayliss
    998SBayliss 4 years ago

    One of your best tutorials for me. Thanks Dave!

  • Javier Gonzales
    Javier Gonzales 5 months ago

    AS ALWAYS, EXCELLENT Tutorials, and Reviews by EEVblog. GREAT TALENT to FOCUS in the ESSENTIALS, and in the Key CORE CONCEPTS of the Electronics in questions, without COMPLICATED "ANATOMY" AND "PHISIOLOGICAL" Explanations as MOST of the Electronics Textbooks and TheXvid Presentations do ! NO EXTRA AND UN-NECESSARY HEAVY WEIGHT AND LUGGAGE !

  • *
    * 4 years ago

    Dude, I hope you make good money an enjoy your job. Your videos are awesome. One of my main resources. With school being so crazy, expensive (and poorly taught). Really makes one appreciate your efforts here even more. So thanks again, keep teachin'!

  • Sonia Rudra
    Sonia Rudra 7 months ago

    Your explanation is so lucid. Thank you Sir! 😊 Will come to yaa videos for more good understanding

  • David Clawson
    David Clawson Year ago

    I wish I’d had this video years ago in engineering school! Thanks, Dave.

  • guzmangalofre
    guzmangalofre 3 years ago +1

    unbelievable, what a master class. this teacher deserves his salary. I honestly want to make a donation. you made my day. I never laughed so much in class as I did in this video with you!! :)) he does not only explain it amazingly well, but also makes it entertaining. 10 points

  • Thomas Schilz
    Thomas Schilz 3 years ago

    Thanks for the excellent video. Having had no clue about OpAmps before, it just helped me to figure out how to drive an LED from a 1.5V battery powered DCF77 receiver with a 5V powered LM358: One half as buffer, second half as a noninverting amplifier.

  • Sam D
    Sam D 2 years ago +1

    I love the way how he turn such a topic to an interesting one....he is a great teacher

  • U M
    U M 3 years ago

    Hi dave, your efforts are appreciated. I want to know can I use the op-amp in buffer state to measure the open circuit voltage of PV panel without disconnecting the load. Thanks.

  • Aaron Goodson
    Aaron Goodson 5 years ago

    Did you ever make a video on op amp limitations? I think it would be very useful.

  • Christopher Wells
    Christopher Wells 7 months ago +1

    Ohmygosh, is that really it? You just compressed my college circuits II class into a 50 minute video! Thanks for the simplification!

  • Don Matejek
    Don Matejek Year ago

    You are awesome, as usual Dave. I had only one great electronics instructor, back then...the rest were crap!

  • Mikael Jansson
    Mikael Jansson 6 years ago +9

    Wow, huge thanks for a crystal clear explaination! I have watched several other videos where others tried to show how awesome opamps are and after those videos I became more confused. At last, thanks to your awesome video I understand what it is and how I can use them. Awesome Dave, it´s like christmas following your videos.

  • Hallvard Aske
    Hallvard Aske 2 years ago

    You are an amazing teacher! Thank you!

  • Dan Aldrich
    Dan Aldrich 4 years ago

    Thanks Dave. I watched this as a refresher for an Engineer II technical interview. They asked all Op Amp questions! Passed it!

  • Antonio Newton Licciardi Jr

    Congrats! You were able to explain Amp Ops in a very fun, easy, didatic way! Very Impressive. Prof. Newton

  • Staros Eugene
    Staros Eugene 3 years ago

    OMG this's easy to understand more than many other videos. Thank you a lot

  • Ross Potts
    Ross Potts 8 years ago +9

    Interestingly I just recently recommended someone to look into using an opamp for their project...
    @EEVblog never disappoints.

  • julien de vriese
    julien de vriese Year ago

    You just made studying electronics much easier, thanks!

  • Gary Mucher
    Gary Mucher Year ago

    I do realize this is a pretty old video. But you gave an extremely great explanation of op-amps for sure. Bravo sir, Bravo...

  • Mangu Díaz
    Mangu Díaz 4 years ago

    very good tutorial, you explained many things I've found in circuits an now I can
    understand much better.

  • jheesom
    jheesom 2 years ago

    If my college lecturer in the 1970s in England had been just half as good as explaining things as you, I could have saved myself 40 years of stress thinking that I was an idiot. Keep up the excellent work, you obviously love passing on your knowledge and are brilliant at doing it. I am now totaly gripped.

  • Pranay Reddy Karnati
    Pranay Reddy Karnati 7 years ago +23

    The concept of virtual ground was delivered precisely.
    Thank you Dave!!!!

  • Ted Sheridan
    Ted Sheridan Year ago

    Great video - I supposedly learned op-amps two-decades ago but never got them until now. Thanks

  • Nadim Ahmed
    Nadim Ahmed Year ago

    i first watched this video in my first year, it has been five years now, but i still come to this video when i need a recap in this topic... yes, he is that good at explaining electronics stuffs!

  • angturil
    angturil 2 years ago

    as usual extremely well explained! Thanks a lot :)

  • shikhar patel
    shikhar patel 3 years ago +1

    Hey by the way great explanation but what will occur when we add a active component in the feedback rather than a passive one what will be the overall effect on the gain and other parameters.

  • Barnaby Wilde
    Barnaby Wilde 2 years ago

    tonight i learned 10x more about op-amps, and with a deeper understanding, than
    i did in a whole semester in a suffocating classroom. Thank you for your time.

  • GranuMuse
    GranuMuse 2 years ago

    Thank you! You are great! But when I tried both of input types, I didn't get amplification to my audio signal.
    Vcc = 5V
    RF = 100
    R1 = 10K
    So why didn't I get 101V gain?