Digital Comparator with OpAmp

[@TheAussiePirate]

I love how you break down complex (to me) circuits and describe them so that I can understand. You sir, have a gift. Thank you.

[@jkuebler89]

Thumbs up for a red blooded American giving a clear and concise electronics tutorial without that same royalty free music all over KZbin obnoxiously blaring in the background! Thanks for all you do brother!

[@shfahim7938]

The best thing of your video is, they are non scripted. So you slowly go through every step, explaining everything. Your videos are soo easy to understand. ♥

[@allabouttech5689]

It's has been a month now I have been surfing through the web and KZbin channels just to find how non inverting comparators work and I was lucky I found this informative lesson today.For this great lesson I have to give you a thumb and also subscribe to this informative channel. Thank you very much.

[@bingojamas4786]

Thank you for the refresher. Just what I was looking for to build my battery backup with yup, a mosfet. Amazing how you sometimes find exactly what you need when you need it.

[@iLuvSoldering]

Oh man. This is what I am trying to find out and since I don't have proper tools can't understand how op amp works. now I am clear. Thank you.

[@michaelpadovani9566]

The more i watch these videos the more things i want to buy! Awesome job.

[@richardfosse2308]

I know right! My wife hates it when I watch Slow Boat From China, Mailbag, In The Mail, etc.

[@gartmorn]

Nice explanation of the comparator circuit and good that you gave us some examples of its use in the real world!

[@iLuvSoldering]

You are a Good Teacher. you have the ability to teach Great things to People in a most simpler way.

[@AdamTheAd-vanc3d]

You defo have a knack of making your explanation easy to grasp and understand 👍👍👍👍

[@learnelectronics]

Thanks, I do it for a living.

[@thetooginator153]

True. As we get old, we forget things. But, it takes decades to hone complicated skills. There’s some irony!

[@H-Visage]

Man this was awesome! Well explained and the demo at the end helped a lot! keep it up!

[@trentjackson4816]

I would have used the LM393 for demonstrating a comparator. By textbook comparators are meant to be active low. The LM393 which has open collector outputs can only swing low, and this is how a comparator is meant to be. The gist of it is basically that if the voltage on the non-inverting pin is more negative than the voltage on the inverting pin, then the output swings low. So suffice to say that the reference voltage is set on the inverting pin.

[@stefstaf]

Thank you sir, you just answered a puzzling question I had. On his LM393 video he connects the cathode of the LED to the IC's Output and the anode (through the resistor) to the Vcc. In this video he connects them opposite (anode to the Aout and cathode to ground).

[@syedabishosainrizvi7817]

6 year old video and the intro checks out

[@WisdomVendor1]

I don't know what resistor values were used in the voltage divider, but a 1k ohm and a 270 ohm will not give 7.5 v....closer to 2.1 v .

[@Atetus94]

I also calculated that and WTF - 2,13V, but if values switched it cames 7,87V :)

[@freshtalatif5571]

I also noticed this, the output of voltage divider at invertng input will lower voltage, about 2 tenth of positive supply, he put the other way around. Anyway the concept is taught, and explained clearly, thank you!

[@Hootz99]

Another great video! Thank you Sir

[@philipgbullas]

refreshing! haha thanks!... and why so many thumbs down! huh!?

[@Santhoshezhumalai]

How to handle with +12 & -12v and ground on IC741 using S-25-12 SMPS?

[@diamony123]

i think this the best way to make a On time trigger circuit by replacing the pot with a resistor and capacitor.

[@TheJavaSync]

More .. more .. more !!!! Loved it !!

[@In3xorable]

It's a lovely circuit.

[@kgparanormal]

another good one, love this stuf. I like the way you change one component in different part of circuit makes big changes so many things you can do that what makes it so fun what can we make next????

[@buddingscientist170]

Thanks

[@pizzzzz3493]

Great teacher ,Great Video ,thank a lot .

[@igrewold]

Great stuff man, thanks a lot.

[@ahmedmohsenshoheb6772]

Hello. Thanks for the video. I want to ask about something though. to get a 7.5 volt at the inverting input; shouldn't the upper resistance be of a value 100 ohm, not 1K? 7.5 v would then be = 10v * (270/270+100) or is there something else Im not seeing here?

[@nilz91]

where can i buy this quad-opamp package using only 8 pins? 1:04

[@hendritresnahadi4146]

Can or canot 741 measure in mili volt (about 100 mv) to turn on or off led with that diferrencial ?Txu 🙏

[@rahulpatelgujratahmedabad3497]

Good tiching karte hai 👌👍👌👌👌👍👌

[@celtichongy]

Interesting material, thx for sharing.

[@rayinoz]

I enjoyed your video. 👍

[@uktoker71]

So something like this could be used as a basic battery protection for 18650 batteries, E.G. disconnect the power when V is less than 3V ?

[@learnelectronics]

+uktoker71 Yes, but you would switch your inputs so it cuts off at low point

[@andrewsotnikov5680]

It's good, but can you explain why do you have 8.5V as output value?)

[@jeffmeds]

I want to purchase TL072 but there are several types. What one do I purchase??

[@jamesmay4547]

what's the val of the pot? good viedo

[@russellreal]

will both a and b be equal to +V if both are active or will it split it in half?

[@doughankins3996]

How would you make it come on at 5v?

[@mbenitez6722]

Where did you get that power supply o:

[@balkrushnakadam7082]

I have question, I used 741 op-amp as comparator, a potentiometer to set threshold at inverting input and a voltage divider using 10k resister at 5v side and a reversed biased photodiode at gnd side to the non inverting input. My goal is to make night light, but in situation when the output led should be off but it is actually not getting off fully it is glowing very low in off condition. But in on condition it's behavior is normal.

[@snowheart1877]

Hi, same problem here, did u manage to solve it?

[@allabouttech5689]

Sir, it's possible to use thermocouple as a sensor and if yes how to use it?

[@NMPVevoOfficial]

Thanks for te video! but how can we get the values of the resistors? since that we cannot choose a random value, what is the criteria to follow? Thanks

[@learnelectronics]

Use the data sheet

[@NMPVevoOfficial]

@@learnelectronics thank you!

[@allabouttech5689]

Sir how can I replace the potentiometer with a thermocouple

[@efesstuff4936]

Can we use a lm339P comparator instead of op amp i couldnt get it to work with a comparator

[@dennysowth7930]

I enjoyed it. And 👍. Thank you sir

[@nabeelahsan504]

What company or model power supply is he using?

[@juanalvares11]

What is the minimum voltage at the vin wich we can use it ?

[@lonewolftech]

Vcc on most comparators can handle from 5-30VDC but make damn sure you look at the data sheet of whichever one you are using.

[@dannyjensen4954]

Very good video

[@georgechambers3197]

Lots of new Patrons congrats. I'm looking for something like a comparator circuit for torch height control on a CNC plasma cutter. It needs to keep the torch height controlled by keeping the voltage at the torch constant. Any ideas for something like that instead of spending $350 for a THC? Thanks for the video.

[@learnelectronics]

Well, you could do a comparator...Set your Vref for the max height, read your Vin from the unit and if use the comparator output to kick on your z axis to lower the height by a mm.

[@georgechambers3197]

Good idea. I'll look into it more. Thanks!

[@markkennard861]

What is the difference between using an op amp and a comparator chip like the LM293. Also what would change if you supplied some feedback.?

[@learnelectronics]

A comparator is purpuse designed for the task, where as the op-amp is more of an all purpose design. Think of it like the comparator is an arduino and the op-amp is a raspberry pi. The pi is capable of so much more than the arduino. The op-amp can be a comparator, or an amplifier or an integrator, etc...

[@phillipneal8194]

Can an op amp respond quickly enough for rf. type zero crossings ?

[@learnelectronics]

That's a loaded question. Simple answer, some are. Read this technical paper, it will give you some ideas and cost vs. performance data: www.ti.com/lit/an/slyt121/slyt121.pdf

[@granumuse7847]

I'm studying for 2 days the lm358 and ai cannot understand the terms "inverting" and "non-inverting". What does it mean in field of electronics??? Of course, thanks a lot! Great video!!

[@Physicsandmathswithpraveen]

Input applied to non inverting input maintains signal output in phase as other inverting input applied signal in 180 phase shifted so inverted or signal out put is upside down.

[@StephenBezuidenhout-y6u]

How too make a timed led with the same components like a traffic lights

[@lovrobebic1447]

I've made similar circuit but when voltage on non-inverting input falls to zero, the output become Digital "1" or 20V, can somebody explain me why this happens?

[@michaeljoshuamanallo1742]

I have a question can I use a lm348 it is a quad op amp but I will use one of the op amps inside

[@learnelectronics]

Yes

[@michaeljoshuamanallo1742]

Thanks so much I love your work Iike and subs of you videos sir👍👍

[@S24W2]

Thank you! Could you please explain what you meant by rail to rail? Also could you do a video on making a simple buck converter? Thank you

[@learnelectronics]

Rail to rail....if you feed the opamp +12 and -12, most opamps can only swing +10/-10. A rail to rail will go from +12/-12. I have done both buck and boost converter videos.

[@S24W2]

@@learnelectronics thank you! Also I don't understand, I tried this and yes the led went on and off when I varied the pot, but it came on when the out put from pot was slightly less than negative input??? I wasnt expecting it to come on until it was greater? Thanks again

[@juanalvares11]

in my opinion the nee 555 timer is a better option becouse it has a better control in the light you can change the brightness of the led with the potentometer

[@MuhammadRizwan-ritz]

how can we make analog audio to digital output using op amp

[@iLuvSoldering]

I Got to Download this video, before youtube removes it.

[@darrenclark6552]

Is it better to use a designated comparator for this purpose or is an op amp just as good?

[@lonewolftech]

Op amps want to keep the inputs the same and will do anything to do so. The big problem with op amps is your reference voltage will vary as your non-inverting inputs voltage varies. This is because they’re analog they operate on current not voltage. Comparators are true to their digital nature even if they’re fairly analog still.

[@21thTek]

Great !!! ⭐⭐⭐⭐⭐

[@knokcs]

my LM239J exit is negative and never positive. V+ and V- are correct. If I want to light a led I need to reverse it. How can I have positive voltage to the LM239 exit?

[@keithcitizen4855]

Elementary electronics , learn about pull up resistors ETC

[@lemonglataitor2123]

I think i might try to use a op amp as a comparator in a D.I.Y 555 timer ciruit.

[@jimedgar6789]

Hahahaha Paul! That is what happens when you get old !

[@lemonglataitor2123]

"Close enough for goverment work" Indeed a funny one he is!

[@jamest.5001]

looks like someone thought this is a talkshow on comparisons. and didn't like the video.. I had been thinking about my voltage regulator circuit. for a alternator. anyway I was thinking maybe it would work better with a comparator thrown in there??? then I get this video. since its basically a voltage controlled switch. that happens to modulate to control the voltage output. and couldn't I make it adjustable if it has a op amp comparing voltages? adjust it at least with in a volt or two ? I still haven't started on the project yet. I need to calculate current draw of the rotor. what is it? volts times ohms equals what? or does it? see I need advice! what I don't know. I make up for by not being sure I know anything to start with... you know what I mean? the replacement regulators are good for 5amps@24v. so I need to know the current draw of the rotor. great video shift registers coming soon??? the more I have thought about it . a comparator wouldn't have anything to compare to!

[@learnelectronics]

Ohms law V= I *R so I = V/R

[@diamony123]

The KISS Method

[@iqnill]

TL072? OK, quad or dual is a simple mistake, but isn't pin 7 the out-B on the TL072???

[@stewartrv]

I was trying to figure this out as I was confused by the voltage divider. If I'm not mistaken the 270 ohm resister should be connected to 10V and the 1K to ground. Am I right? As it was shown on the schematic the current would be 10V / 1270 ohms = approx 7.9mA and therefore the voltage across it would be 270 ohms x 7.99mA approx 2.13V rather than 7V. If the 1K was at the bottom (ground end) it would be 1000R x 7.9mA which is 7.9V approx. Of course it woun't be exact due to tolerances etc. So am I going nuts or did you switch the resistors (I was having trouble trying to read the color codes on the video) ? I know it hardly matters for a comparator but I thought I'd check...

[@learnelectronics]

Watch today's video, totally my bad....

[@stewartrv]

learnelectronics OK not a problem I have HAM exam tomorrow and thought I had something wrong. Thanks for the fast response! Great job by the way!

[@j.clowers7223]

Awesome.

[@tamarabarnett9869]

Kool.Thanks.

[@mattantonelli4273]

Great again

[@Who5tealmynamE]

Dope intro :DDD

[@killya4492]

hello sir. can i ask what i need to hook this into 220v line. i want to use this comparator circuit to send a signal to relay to cut off the line if the 220v line was touch. this is for my project. it will be my pleasure if someone would help me💙💙💙 thankyou so much

[@learnelectronics]

This is a low voltage DC circuit it will not work on mains AC.

[@juanalvares11]

basically like the n 555 timer

[@alicekichlu215]

I AM NOT ALWAYS SURE USING MICROCONTROLLERS IS PROGRESS.

[@learnelectronics]

I agree

[@robbs96]

Noob question here. Why not use a zener and a mosfet?

[@igrewold]

my comment got nothing to do with your Q sorry ;D But honestly if you wanna make it into electronics (for real that is) you gotta read the book: Art of Electronics (preferably latest edition) also get the manual(lab work for learners) and the required components. Little dedication and lotsa labs, next thing you know, you are posting something on Hackaday! ;D artofelectronics.net/ Good luck and Godspeed.

[@learnelectronics]

+Robbie Robinson Zener and MOSFET for what?

[@robbs96]

learnelectronics as apposed to a comparator. If i want to turn something on at a specific voltage why not use a zener at that voltage to drive a mosfet. Or even a programable uni-junction transistor for that matter. I know its probably a silly question. So please be patient. Thanks

[@learnelectronics]

+Robbie Robinson Ok I understand. This is a digital circuit. What you are talking about is analog. Just different types of circuits.

[@robbs96]

learnelectronics there would be an analog input to my circuts, as you have here with a pot. But the output to my circuts would be digital,just like yours. As long as my mosfet is in saturation right?

[@remediusfernandes1570]

Thanku sir

[@ionchilug-lu9nm]

Eu nu îl pot adapta la etajul cu ir2153

[@russellreal]

can you use a tl702cn? What is the naming convention? is anything TL702**** an opamp? Can they all be used similarly? This electronics shizz is complex lol

[@kashyapkoshti]

It is dual op amp not quad op amp

[@neilgroves3592]

informative lesson but your breathing into the mic Is kinda creepy....

[@learnelectronics]

Sorry. Its cause I'm dying from congestive heart failure and use oxygen 24 hours a day. I'll try to die less creepy from now on.

[@neilgroves3592]

@@learnelectronics sorry to hear that, maybe a pop filter in front of your mic would help?

[@uploadideaswithitamar]

Thanks