Analog Constant Load/Current Controller Circuit

$2/5pcs 2Layer & $5/5pcs 4Layer PCBs: jlcpcb.com
🔥This time I've made an Analog constant load/current controller that is using an OPAMP to control the voltage at the gate of a MOSFET and by that change the voltage over a LOAD. In this way we control the current flow and by that the load value.
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LINKS
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Tutorial: electronoobs.i...
Tutorial Website: electronoobs.c...
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Schematic: electronoobs.c...
Code: electronoobs.c...
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ADS1015 library: electronoobs.c...
Test video: • Constant Load Controll...
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#Load
#Controller
#Circuit

[@ELECTRONOOBS]

Sign up at ELECTRONOOBS.io: electronoobs.io/ Follow me on FACEBOOK for more: facebook.com/Electronoobs help me on Patreon: www.patreon.com/ELECTRONOOBS

[@md.mostafakhan4529]

I tried to make one an year ago. Target was to make one that can handle 30 volt and 20 Amps, but failed to do so after burning couple of mosfets and power resistors. This circuit is interesting and challenging me to try that project with this circuit. Will try. Thanks dude.

[@Danixu86]

600W is a lot of heat... is normal to burn some componens xD

[@Mr.Leeroy]

water cooling

[@Passco666]

Then try to use oven instead mosfets ;)

[@user-sd4ls4dr4p]

Hi pliz can you send to pe the circuit of power electronic load

[@Taran72]

Awesome Project!! I cant wait to watch the video for the PWM load control!! Thanks. This project is next on my queue.

[@ELECTRONOOBS]

Glad to hear this. Thanks!

[@flos251]

Nice project. 11:58 I think this are 0.01A and not 0.01mA I would add a button to change the units between A and mA to get more precision

[@Brainwizard.2]

Thanks alot for this video. I have been crunching my head about constant current sources and constant voltage sources the last 3 days. After that i have realized my minor deep understanding of "current" and "voltage". So funny. I study in the university and i never thought about that. So funny, that i could pass the exams for analog and digital electronic without knowing that. I guess that relates for many in university. I have also seen Ben Eaters Tutorial for 6502. Your contents revolutionize the university and newbees by far with a more practical approach! You are great!

[@anurasenarathna1703]

One of the best explanation on electronic dummy load. I will be building one. Thank you.

[@klave8511]

Excellent presentation and style well done. I have a few reservations about this project! You explain using only one op amp then use another to buffer the pot. This is not necessary. You use 12V because the gate voltage is added to the sense voltage and 5V would never work at high currents. You could use a single transistor to shift the op amp output and could get rid of the first op amp. The LM324 has spare amplifiers, you should explain what to do with them (maybe I missed that part) The current is set with a resistor referenced to the 12V, this may be accurate under one set of conditions but it is better to use a regulated voltage or a reference voltage. Why do you want 16 bit precision, realistically 10 bit precision is enough for almost any real load. For speed of response this analog circuit will always be better than a digital version with PWM output to set the fet gate voltage, many active loads are used to test transient response, the analog circuit will be better because PWM will be too slow.

[@RomanoPRODUCTION]

-Ola me llamo Juan et soy especialist in neomaticos- Thank you for feeding even more electrons from the digital source :)

[@MrGenia1991]

cool project. how about to make RC plane with atmega8 inside ? :)

[@gabrielquarshie94]

Ohh you are doing well. Thank you for the tutorial. Im going to follow step by step and build one.

[@backdemoletor4654]

This channel usually offers good projects, like this one... Keep it up

[@BenMitro]

This is great and simple. Looking forward to the digital constant current project too. Can you also include AH and WHr readings? Another thought is have it connected to a laptop or PC to control power and display results for example, to discharge batteries and measure their capacity.

[@newdaynewdose9692]

always exicted for your videos

[@electronic7979]

A great video. You explained the subject very well. I liked it.

[@naiwidya1854]

Thank you very much from Thailand

[@nalinux]

I made a current limiter a while ago, but never thought about using an Arduino to check the amperage :) Good idea.

[@MOZARTF]

Looking forward for the pwm version. Thanks for another great video!

[@dominikworkshop6007]

Cool, but this load cant take 5A, because of the 1ohm 5W resistor. At 5A this poor resistor would dissipate 25W!!!

[@ELECTRONOOBS]

Yes, sorry I haven't mentioned. Just use a 100w resistor of same value and that it.

[@FixDaily]

@@ELECTRONOOBS no need for 100W resistor, you can use a lower resistor's value, like 0.1r and amplify it with an OPAMP. You'll have a lower voltage drop, which will allow you to have more current flow with less power dissipation. You can easily get 0.1R resistor from an old laptop.

[@josefaschwanden1502]

@@FixDaily there are even 10m ones

[@FixDaily]

@Matix1710 with 0.1r at 1Amp you'll have 0.1V voltage drop, if you want to increase it to 1V you need to amplify it by x10. You can't test this using a breadboard, you need to solder this so you decrease the resistance over contacts, otherwise you'll have no control of it.

[@BeetleJuice1980]

we need the digital version! great work!

[@SIKHGT650]

Now that's a great project, can we shrink it with small lcd and much amp capacity......

[@koshan12]

Epic video as always, and one suggestion for the digital is to make it to count the capacity of batteries

[@astesla369]

New subscriber from India👍

[@lennard7123]

Awesome project, when will you do the digital version of this project? :)

[@Haamedtm]

That 1 ohm 5W resistor will melt under 5A of current!

[@farhadsaberi]

yes you are right. I don't understand the resistor value he is using. At 5A the 1 ohm resistor must dissipate 25Watts. But he is using a 5W resistor instead of a 50W resistor.

[@GreatSpike]

Nice project, nice animation by the way

[@sefalibhakat143]

How many of you like basic videos like this. If yes 👍👍

[@MahmudulHasan-eq7ug]

Great video. 7:40 It is quite ambiguous. You probably could have explained.

[@amciaapple1654]

The inductive Current Sensing Resistors will create circuit instability at higher frequencies.

[@rissole7229]

Excellent project. I have been following your channel for some time and so I built this project with excellent results. Keep the projects coming!

[@gabrielquarshie94]

Master, U mean U did the same thing ?? Then you are SUPER.

[@ashwinbhandari6979]

You got a new subscriber.

[@SudhirKumar-bq4xz]

Nice project..... Stay home.... Stay safe....😀

[@usmanumer9871]

beautiful heat sink

[@RobertBercovitz]

amazing work

[@user-fm5fg7yh5h]

Nice work

[@tomgeorge3726]

H, great project, can't wait for the next version.👍😊👍😊 At 3:17, you said precision of 0.001mA, I think you mean 0.001A or 1mA...😮😮 At 12:00 0.01mA, I think 0.01A or 10mA..😮😮.

[@ELECTRONOOBS]

yes, my mistake when reading the script... sowy!

[@MitsuZer0G]

3:55 Wait a second ... You connected these tiny cables to your power supply and shot up to 5 Amps through then? How did they not melt? 🤔

[@parameshpavin2708]

Nice one i liked it please make a digital version also sooner...

[@farhadsaberi]

Can you please explain the 1 ohm 5W resistor? At 5 amps it will dissipate 25 watts of power. But you are using a 5W resistor. (P=I^2 * R) Why is the resistor not smoking and blowing up?

[@SyedMaruhomOrante]

thanks

[@BharatMohanty]

Man that heatsink is huge...

[@bashaaksema94]

Well actually

[@ranasaad7456]

Awesome video but i am waiting long for your PIC Videos

[@niklasblattner3146]

Just crashed your Spitfire model today, keep up the amazing work!

[@ELECTRONOOBS]

I never got to test that model....

[@niklasblattner3146]

@@ELECTRONOOBS you should try it:)

[@Nono-hk3is]

I love the analog circuits! And the upcoming comparison with their digital counterpart. Speaking of comparison, could you explain what differential pins refer to on the a2d chip?

[@Regimantas_Baublys]

Check current with oscilloscope you see current pulsing with avarage is you current. Because mosfet gate capasitor op amp over compensate and undercompensate. Better use darlington BJT. Alternative add capasitor at op amp pin and output pin :) I made same mistake :)

[@ahmadmaaz2566]

Very awesome video with a beautiful explanation... Keep it up sir... I wanna know that... Can i use this circuit for variable load as a controllable current source??

[@bryanwhite7656]

KZbin seems to think that the audio for captions is in Italian. How can this be changed?

[@cantotrapt]

nice project, but I would use thicker wire for your load, if you are going to use large currents.

[@tash213]

Nice animations

[@zanmarinic]

Great project! One thing though why do you have the voltage follower infront of the "main" op amp? Dave have the same circuit (more or less) and he said that it's there just because he had a pcb with that schematic laying around... Thanks for the answer and the video! Best regards!

[@siddharthmali5841]

Great. Make digital version soon.✌️✌️

[@EdgarLTShadow]

They could also carry out this project based on the attiny85 or use a screen that has a voltmeter and ampere meter without microcontroller

[@sidyajv]

Excellent

[@paulabraham2550]

Aren't you overcooking that poor little resistor a bit at 5.2A? For a 1 ohm resistor I make that a dissipation of 27W - way beyond the 5W rating. Or am I missing something?

[@arjunramesh6383]

Hi ,could you please make a video to measure ac current flowing through a conducting wire ???

[@aakashprajapati9752]

It's really cool #uniqueelectronicidea

[@alexandrebelangerlamonde2647]

Very nice, this is a way better way to get a constant current than what i have found. Currently looking to build a DIY lipo cell capacity tester that can deliver 5 amp charge and 10 amp discharge for a single cell and this will help me greatly. Could you use an analogue output with op amp gainer to supply the voltage that the potentiometer is giving? Use the arduino to supply voltage between 0-5v and use a gain of 2 to have a signal from 0-10v and so 0-10 amp possibility?

[@prabirdebnath5197]

Nice cool project. Could you please confirm the maximum current we can set

[@RomanoPRODUCTION]

Nice noob video, pretty refreshing for really practical testing

[@andymouse]

Very interesting...cheers.

[@dazrich20]

Well you read my mind. wanna make a car warmer to defrost the car since its now summer got an aio water cooler and a heater bed(lets change that to a mossfet or 2)(why dont I just use a resistor) and a bit of ally. but need to limit current this saved me googling :)

[@ranganatennakoon]

nice thank you ! ! !

[@bashaaksema94]

Can you show the current wavefrom on the oscilloscope?

[@renelefebvre53]

No waveform, all are in continu voltage .... no Ac anywhere

[@przoch5835]

hi very interesting, it is something I was looking for. Just wondering if power dissipation through Mosfet shall not be taken into account as well ?

[@nabilandadamslaboratory3422]

Upload the English version of the Spanish video you did about motors and encoders

[@YakubKristianto]

why N-channel mosfet is used at the high-side? is there specific reason to use N-channel instead of P-channel mosfet?

[@motilalsuthar4048]

Doubt: Arduino nano is an 8 bit microcontroller and the external adc used in this project is a 16 bit . Is this setup compatible????

[@asifehsan4948]

Hi sir, very good project with good information. I wants to make it for 20 ampare. So what components I change and is any changing in code? Please advise me

[@hrithikhu]

Can you make your own version of Smart mirror... Plss With features like face recognition, video streaming, home automation, social apps and much more.

[@Novus_Ordo_Conditor]

so can this system be powered by a more powerful mosfet?

[@michelbrasseur9296]

i'll make one with button for the interface and a 300W one by putting mosfets in parralel or using IGBT ( maybe with watercooling idk )

[@Lackenboden]

did you already build one? I heard IGBTs are a bad choice for that.

[@joserolandsancheromero4440]

Pon el video en el canal que es en español porfaaa!!!

[@davidfade7538]

Can you make digital tone control with lcd display?

[@davidfade7538]

Plss help i need to make my Amplifier

[@dharmakissoon]

hi with the heat dissipater ,is that wasted energy ?

[@mikelund1876]

So this controls the current from the power supply so where in the circuit would I add the circuit I want to supply this current to?

[@atec9228]

Todos tus vídeos son geniales. Te quiero preguntar,con que programa haces la edición de vídeo??. Me gusta mucho cómo haces el texto que se queda flotando junto a un componente queda muy chulo. Como lo haces??

[@ELECTRONOOBS]

Con after effects

[@fortefortisimo2]

Hi, i bulit this circuit but i replace Arduino on mulimeter and i have a problem. Now all of my mosfets are broken (irlb3034 and p60nf06) Everything is ok when i tested this with small power supply(9v 1a) but when i plug computer ATX MOSFET are dead ( D-S is constantly open) Anybody can help me?

[@user-vs3so9ic8q]

can this project can be applied on the ac circuit? and also can be integrated to IoT?

[@baseandtrance1110]

Hi @Electronoobs. I wanted your help in the brushed drone project in how to change the motor pin since instead of pin 9 I want to use pin 7 and can we use that same code for brushless drone. please help

[@hunkbol6154]

cool i like it sir )

[@bobdoritique7347]

Hello. Are you sure of the schematic on your website? I think you have inverse the + and - to the amplifier. The - is use to the retroaction mode.

[@ELECTRONOOBS]

Hi. True! Sorry, my mistake. I've just updated the schematic! Thank you!

[@bobdoritique7347]

@@ELECTRONOOBS In France, we say: "only the one who achieves things makes mistakes.". Thanks for your videos.

[@ziko2371]

Still bad inv and noinv pins on sch

[@BLACKArracknet]

I think you should have used 2 or more MOSFETs in parallel to reduce heat losses.

[@EasyOne]

perfect

[@ranjithshetty7078]

Make inverter and ups pic control program please sir

[@incxxxx]

Why you use second OpAmp when one of them would do the job ??? Anyway the OpAmp inputs consumes almost zero current.

[@SIKHGT650]

Can you please make load and energy meter with small lcd like rc amp meter available on AliExpress with 150-200amp...

[@jamiuadegboyega2751]

This is beautiful... What software do you use for the animation and simulation?

[@ELECTRONOOBS]

I use after effects

[@rezanulhaque2454]

Big follower of your. Please we want to learn the code for sine inverter.can you please make us understand!. I watched ur inverter related video . But want to understand the code .

[@dragonexecutioner1715]

Could we add a bjt? Instead of a MOSFET

[@milanmakwana3883]

I need 100Amp 2 volt source can you help me

[@SiriusFuenmayor]

It is possible to make a modfication in order to be able to invert the direction of the current?

[@nekelly123]

Hi, did you use the external ADC for better resolution or because the internal Arduino ADC is unreliable? I don't know if I'm doing something wrong but when I try using the internal ADC, the readings fluctuate quite a bit.

[@Paloky.3]

Hi Electronoobs. Two simple question... Why do you use the differential mode to measure the voltage drop on the 1R resistor, if it is referenced to the same mass as the ADC? The second, is because you don't directly use the ADC of the Arduino nano itself? Is it because of the 10 to 16-bit resolution? Thank's a lot.

[@ELECTRONOOBS]

No, is not about that. Under a lot of current there is a voltage drop on the wire as well (wire also has resistance) and we only want to measure the voltage drop exactly on the load of 1 ohm. After making tests, the differential mode was a lot more precise. Otherwise we get wrong values with a small offset dependent on the current so is not a constant offset....

[@arminth]

The pin numbering of the LM324 in the circuit diagram on your Tutuorial Website is incorrect.. + and - inputs are reversed! It says + is on pin 2 and 6 but it is actually on 3 and 5. - must be on 2 and 6!

[@willsggl]

Ahaha 😂 correct, aptly named noob, much better to correct ya mistake then leave it online

[@Hubert7323]

Hi, Variable voltage used to control MOSFET gate is a bad think. For ex. better method is a PWM control MOSFET with MOSFET Driver.

[@ELECTRONOOBS]

Hmm...that would create current spikes at each PWM pulse and I would only get the mean value of current. In this case we need more or less linear constant current value..

[@Hubert7323]

@@ELECTRONOOBS Yes, its true, but in many applications for ex. ~1kHz PWM it doesn't matter. In your device control by voltage on GATE can be considered correct cause all power will lose in MOSFET. In typical app when MOSFET control other device it isn't acceptable.

[@GustavoGalarza]

Haz este proyecto en tu canal en español...!!!

[@AnandBhatB]

75W with 5W resistance?? What did I miss??

[@ELECTRONOOBS]

@@AnandBhatB pretty much all power is dissipated on the mosfet and not on the resistor.

[@AnandBhatB]

@@ELECTRONOOBS resistor is in series with MOSFET. So current will be same. So if source is supplying 5A, same will go through resistor. P=I*I*R = 5*5*1 =25W across Resistor and 50W across MOSFET??? Still too much for a 5W resistor

[@sza1940]

Why are u using differential measurement for the ADC at the current shunt resistor? isn't the PSU ground and the load ground is at the same potential? The "Load In -" (V-) is connected to GND, so a single ended reading to "Vres" should give the correct measurement.

[@ELECTRONOOBS]

Yes, but even so, the wires resistance will create a small village drop at high current. So is better to measure the volate in differential mode directly on the load. After tests I got to that conclusion because I had offset values of error...

[@sza1940]

@@ELECTRONOOBS ah i see, thank you for the explanation

[@electroGoal]

Can we use digital potentiometer.

[@renelefebvre53]

yes, with stm32 or Atmega328 , the pwm are use for generate the voltage for drive the op-amplifer. You could use rotative coder and store the value in eeprom for the next use

[@srinivass2836]

Dear sir. Very nice explanation. But please speak little sloely

[@EnergySeeker]

i like that power supply where did you buy it from ?

[@flos251]

The powersupply is "RD6006". You can buy it on AliExpress, Banggood, Amazon, eBay or locally