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Aliexpress:
2x LM324: s.click.aliexpress.com/e/_d8E...
6x 10k Trimmer: s.click.aliexpress.com/e/_dTF...
6x 2k Resistor: s.click.aliexpress.com/e/_dTP...
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Ebay:
2x LM324: rover.ebay.com/rover/1/711-532...
6x 10k Trimmer: rover.ebay.com/rover/1/711-532...
6x 2k Resistor: rover.ebay.com/rover/1/711-532...
6x 5mm LED: rover.ebay.com/rover/1/711-532...
1x Boost Converter: rover.ebay.com/rover/1/711-532...
In this video I will show you how we can use the classic LM3914 IC to create an LED Battery Level Indicator. Along the way I will show you how the IC works and explain why it is not the most precise circuit for a Li-Ion battery pack. And at the end I will show you how I created my own, more precise Battery Level Indicator circuit with a couple of simple components.
Websites mentioned in the video:
www.powerstream.com/p/INR1865...
www.akkuteile.de/
lygte-info.dk/review/batteries...
www.akkuteile.de/lithium-ione...
Thanks to JLCPCB for sponsoring this video
Visit jlcpcb.com to get professional PCBs for low prices
Music:
2011 Lookalike by Bartlebeats
Killing Time, Kevin MacLeod
(incompetech.com)
Brilliant! A project using a couple of IC's and not an Arduino or Raspberry Pi in sight, what a breath of fresh air :)
@Petronilo You missed the point, NO PROGRAMMING is required!
i'm not a big fan of promotions or adverts, but i want to thank you for putting something relevant (jlcpcb) instead of something completely unrelated (like lootcrate or something)
l o o t c r a t e
@@camilomason4560 is shit
raid shadow legends
@@varunsreedharan5347 is more than a piece of crap lmao
i honestly have no idea half the things you said in your videos but it stills captivate me every single time
Even the GreatScott archive still has huge value today. Thank you for all your time and effort!
Over the past 4 to 6 years of watching your channel, I have seen many of your neat projects, but this one, is really well explained, and thought out. Thank you
Man, I just love this channel. It's so educational and provides hours of entertainment. Keep it going GREAT Scott!!!
I have created many beautiful circuits with LM3914 and LM3915 =) I love these ICs!!!
Electronics Projects - Stefano91ste me to
I just searched how to do this about 3 hours ago and now you upload a video on it. Crazy coincidence.
Just a tip, a dash "-" in a model number is just that - a dash, not a minus. I get super confused when you say minus.
a dash is *
Brandon Garven Wait what ?? Why Dash - Multiply *
. dot , comma - dash * asterisk / forward slash + plus
Yes, the DVD Forum would get angry if you call DVD-R DVD minus R.
Technically a dash is longer. A single '-' is called a hyphen. A dash is often made up of two hyphens unless the font you're using supports a true dash like an em-dash (-). But most people call them dashes anyway, including me :D
The quality of your channel is unmatched. Awesome!
This video really saved a lot of my time. I made that LM324 battery indicator for my little Li-Ions, working Great.
I have been watching your videos religiously for over a year and a half. I have not learned a single thing. I will still watch your videos because they are great. I truly suck at electronics and have not gotten anything to work as I truly don’t understand how it works.
Every time I click one of your videos I find myself still watching hours later =P Thanks for the great content!
Hf man hurt free
Same!
Dude, I am amazed by your skills. It is just unbelievable, at least in my world.
The LM3914 is an interesting chip. We used to make crude oscilloscopes combining a LM3914 and a 4017 decade counter /decoder. Thanks for another great video!
You're welcome :-)
The LM324/4017 O-Scope would make an ideal project. Would probably include 4011's or 4093's for trigger control and time base.
Thanks for the video! I‘ve built a similar battery level indicator for my lead acid battery a while back. Of course, if I draw a lot of power, the voltage collapses (even though the battery is still charged) and the battery level doesn‘t show the charging state correctly anymore. You have to keep that in mind, but since LiPos are offen built for high current demands, the problem shouldn‘t be as big.
I waited for this video a VERY long time. Thanks Scott! Been a subscriber for about 5-6 years now, if I can remember correctly.
Thanks for watching :-)
Thanks for being the KZheadr you are. Btw got a quote I think you might like. I think you said you were self-taught to program the Arduino so I believe you did this: "Code to learn. Not learn to code."
--> Learning by doing ^-^
StormyIceLeopard please, if you need a battery indicator like this, a much simpler solution is to either use one of the specialized "fuel gauge" ICs that are designed for this job or use any small microcontroller that has an ADC. Then make a lookup table to compensate for the nonlinear discharge curve. A much easier, more compact and a lot more robust solution than having to tweak 6 pots (and making sure they don't drift or move!). I like GreatScott's videos but some of these constructions are best kept only as educational experiments and not really deployed as a practical solution.
@@TheIceLeopard that makes sense and is a cool saying.
It's quite a good project an I never thought about making my own IC clone. I have solved similar problems with a high quality frequency generator and a microprocessor, for detecting the actual charge, which is total overdoing. Well done, my friend!
You can find the LM3914 in old electronics that have indicator lights for the control buttons. Most things that have the play rewind eject or record or dials that light up.
In this method, you're not consider voltage drop of internal resistance. State of charge value may have different terminal voltage according this relation: V=Voc-R*I, (V=terminal voltage; Voc=Open circuits voltage, R=internal resistance). Two simple method for SOC estimator are: 1) Coulomb counting: integration of current in time. 2) Soc(voc): inversion of R-C battery's model.
But he can also just use his indicator circuit while the main load is turned off. So V = Voc
Open circuit voltage isn't very useful, Gordon. Li-ion cells, particularly tired ones, will experience quite a bit of rebound after a surprisingly short period of time. You can have a battery that is effectively dead and sagging down below 2.7v that rebounds above 3.2v before you can get your multimeter leads on it. Lygte-info.dk (where GreatScott! got his battery curves from) has an article on this.
That's true. I assumed a situation were he used a quadcopter for instance and immediately measures the remaining capacity after usage
Deine Videos sind echt gut gemacht und super informativ! Weiter so @GreatScott!
Nice video as usual. Very informative. Keep up the good work
SO surprised that you don't have 1M subscribers yet. Your videos are awsome!
Finally!Thank you for this video.Loved it!👍
Awesome work, dude! Really nice! 😀
Could you not have made one with one RGB LED and change the color based on the power level?
Possible
You'd have to choose 3 voltage points and hook up each to one of the 3 colors. I currently can't think of a way to make a combination color of rgb while still being able to choose r,g,or b by itself. Maybe through the use of diodes to prevent two or 3 pins from being permanently connected?
there is a prob, some people are colour blind
or you can use a cheap ass Attiny 13 and some coding, damn, uC is so cheap now
That would be cool
Well this was well timed, I was reaserching this chip last night.
It's crazy how they stuff all these components in that little chip package
My favorite chip!! The bar graph ic! That was the first chip I used to make a pcb and the one that made me understand how analog circuits work.
Nice project! Just want to point out that the discharge curve changes dramatically depending on the current draw, but perhaps you used the curve that will suit the draw of your specific project. :)
This is some cool stuff, thanks for sharing :)
I just like his video no matter what... this guy is a legend
I was just changing batteries today in my wall clock and I thought it'd be cool to have something that just takes in a couple of AA cells and lets me know how much juice is left in them(for testing my remaining stash of batteries). Boom! Here it is!
Great Scott! Thanks for explaining what is required. Doesn't an arduino have AtoD that could be used measure volts with the discharge profile in rom? Load could then be incorporated into the result with multiple profiles per battery based on current of battery. This could then be used to detect charge/discharge modes and show the actual state of charge under all conditions. That would give you a universal battery state indicator. Could extend it to measure individual state of charge per cell through switching the cells into the AtoD. Using leds for level is a great idea, 10 leds make a lot of sense intuitively, though 4 is probably adequate. What am I saying? You've essentially given me another project to do....one day! Cheers, and thanks again for your fantastic video series - I enjoy them immensely.
Thank you for this video. It helped me so much!
great video :) been waiting a while for this one
That's a nice 2.5bit flash ADC you got there.
Mal wieder ein sehr gutes Video du hast immer sehr guten Kontent mach weiter so👍
Very nice approach, using the old and good analog way. I made myself a flashlight using an Arduino Pro Mini to control the power led with an external Mosfet and LC filter for PWM. It worked as a charm, and for battery capacity I measure the voltage with Arduino and made the flashlight to blink from 0 to 9 in morse code.
Good idea
It's not bad if you are using alkaline primary cells. But with Li-ion cells under high loads there isn't much voltage differential between 80 and 20 percent unless you have a large amount in series.
Sir, I am a hobbyist in electronics and surprisingly I am 13 years old. From 3 years I am watching your videos and they are literally awesome but slowly the topics are getting boring. So, I am requesting you to make an interesting video. And ya! I am from India. Thank you Your Genuine Viewer
Great video scott!👍😁
i was waiting for this video thankyou.
Constant current output 🙏🙏 it's so beautiful
I always like your videos!
I absolutely loved this video, it was perfect and beautiful. There is nothing wrong with it, i actually have no complaints. But I have one complaint, the LEDs weren't RGB. It would have been cooler if all LEDs were on and they were all green if the battery is full, and the colour slowly changes to red and less LEDs get put on as the battery is closer to death.
Very interested in the intricacies of charging li-ion battery packs. I see a lot of conflicting information about BMS boards - mostly about whether they're actually effective. Could you do a video on that, maybe test and review some boards for, say, 3s or 4s?
Sir your voice and explanations are very nice......
Great video and explanation 👍
You don't need a boost converter! Instead use a reference voltage ic or zener reference, that is lower than the lowest battery voltage. The best approach is to go with TL431 Precision Programmable Reference which will give you 2.5 Volts (Adjustable). Then divide the input voltage using a resistor divider so that it is lower than the 2.5 when the battery is full. You can use one of the LM324 op-amps as a buffer.
LM324 already has a voltage reference built in.
Great work dude.
Great video brother!
Awesome project !!!!
Another interesting project! Thanks
posted 15hours ago... what?
A few points. 1) You could replace one of the LM324 with a LM358, as you're only using 2 of 4 opamps. Less power usage. 2) The 20V supply is not needed, use a voltage divider to reduce the voltage from the battery so you only sample say half of it. Not complex, 2x 10k resistors in series across the battery, then connect the inputs on the Opamps to the middle of the two resistors. 3) It should be pointed out the max supply voltage for the Opamps is 32V, so your limited to 7 lithium cells in series (aka 24V nominal voltage battery).
I was thinking the same while watching the video. We can use a reference voltage ic/zener which is below the discharged battery level voltage, then use resistors to make voltage divider to scale the 0% to 100% voltage levels inside that reference voltage. That way the circuit can even be powered by the battery itself, and obviously no need for boost module :P
Nasha UT probably use 3915 or 16, one of them is logarythmic like the battery curve is. As we all say it could be done more simpler.
Why don't you use a simple linear regulator to get the constant voltage for the circuit and devide the battery voltage with two resistors? That way you could get rid of the boost converter.
Good idea
Yes.
Make a video about this ! Thankss
Cle mens efficiency?
Boost converter would be less efficient than a voltage regulator
very nice video bro i like ur videos love u tc
I using a microcontroller, ADC and lookup table, I also massure the current flow and calculate the total consumption, it's easier and more accurate
YEEEEEES FINALLYYYYY THANK YOU CARBON UNIT
Nice project
Very nice video I like ur video 👍
Nice Video, thank you.
You're a master, sir
Perfect bro you are a real creator 😜😝
This could be done with a single op amp, LED's, resistors, and nothing else, exploiting the voltage drop across the LED's. Add a bridge rectifier and a capacitor to smooth out the flickering and you can measure AC with the same circuit(Like audio). The only down side would be the LED's fade gradually instead of giving harsh steps, but I think that is a good thing. The non-inverting input of the opamp is connected to the battery, the inverting input is a voltage divided output to set the gain(the gain depends on how many volts it takes to overcome all of the LED's forward voltage at the batteries max voltage), and each LED is hooked in series, each with their own resistor to ground. The resistors to ground could be set as to produce a non-linear behavior of the LED intensity as well, to account for the non-linear discharge curve of the battery.
whatever you said and did was just AMAZING, even though i didn't understand what's exactly is going on...😂😂
Did mine with LM339. Because they were in the bin next to me :D
Woww you are great great scottt!!!!!
Another possibility is to still use the TI part, reduce the number of LED indicators from 10 to, say 6, and use certain LED to display the voltages that you chose on your design. You can also set a min voltage set point as another degree of freedom. No need for so many pots.
Good job man
That’s beautifully precise! Nice job!
that was awesome!
Best channel, i'm brazilian
I learned so much from this one video. You should do some math videos.
Yes matter how hard it is, just don't get discouraged. when to buy!
So it's a flash ADC but without the logic to convert the output to binary. I made one of these from op amps as one of my first IC projects. I connectected the input to the capacitor through a buffer on a 555 in astable mode. Didn't think to use it as a battery tester. Maybe as a VU meter. The lm3914 definitely makes for a much smaller circuit than having 4 or 5 dual op amps connected to a ladder resistor network.
thank you great episode , but how do you know about existence of such ICs ?
Thats works with only resistors and leds in series too, without a problem And dont forget on lion cells most capacity sits between 3.8 and 3.5 v where on lipos you shouldnt go lower then 3.8 at all
This works assuming you don't draw any current from the battery. The voltage will fall as soon as a load is put on the battery. Like if you are drawing 10A from a 4.0V lipo, it's not going to stay 4.0V forever. Maybe for a future project, have a circuit measure the current being drawn and compensate the voltage thresholds? Other than that, pretty good video.
BoomBrush the drop under draw depends on the internal Résistance of the cell , that voltage sag isnt calculated in most power indicators
Peter Zingler Quitw the opposite - most consumer devices show the battery indicator while using them, so it’s important to be able to use this indicator while using the device itself.
Artūrs Savickis most consumer devices doesnt drain enough current to create a large voltage drop
I came here to say something like that. The voltage is never decreasing in a linear fashion, it will bounce up and down depending on use. Yes, in the long run it will steadily go down, but for shorter periods the values might not make any sense whatsoever...
Yep. This is really a bad design for a battery life indicator, especially for LiIon. Correct solution would be a current sense and coulomb counter circuit. Better still would be NOT using a top-balancing BMS. (Unless you hate your batteries.)
Wonderfull entertainment and indeed I learned something.
Hi Scott., thank you for the great video. This chip can only be used to indicate if battery charging is completed based on signal, Rhi and Rlo. However, without the charging power, can we use the power from battery alone to indicate its voltage level whether it is full or close to being depleted.
Great video most informative. Are you offering any DIY kits for 3s, 4s and 5s 18650 Cells. The ones I am finding today are either plagued with issues or simply do not work consistently as offered. Thanks!!
Sure, the logarithmic voltage decrease may make a slight difference, mainly when your battery is practically empty anyway. It's not really worth the effort of correcting for though, both versions are very inaccurate since they are purely based on the voltage which changes significantly under load. Your battery indicator will jump up and down when you connect and disconnect large loads. If you want a reasonably accurate and steady battery level indicator, you'll have to measure the current draw and added it up to see how much of the capacity has been drawn (like laptops and phones etc. do to determine the battery level) and use the voltage to correct for inascuracies while the battery is not in use. It's not quite as easy as it sounds, since your battery's apparent capacity will also change depending on the current draw, the voltage the battery is pulled down to and even temperarure. Making an accurate battery leven indicator really isn't that easy. But your version is the least accurare, at least assuming you use your battery, at rest I'm sure it's relatively accurate. Of course it can still be very useful, especially considering that you get similar battery level indicators like those for a euro/dollar/pound or two from China, but it may be worth mentioning, that it's only accurate at no or very little load.
Cool video! Really like this project. What about doing something like this with a VU indicator for a DIY audio system or similar??
5:45 This is why EVs tend to use coulomb counters rather than relying on voltage. That voltage knee is abrupt in practice as well. Especially since voltage will sag under load.
So very interesting.
LOVE IT!
1 oled 1 microcontroller a voltage regulator, a few passives job done with way smaller sized board
nice video thanks✌😘👍
Great stuff but this will not work with high current applications since the voltage of Lithium batteries sag quiet a bit under load (depending on current draw). Love your channel btw;)
Excellent work ! Highly useful... But sometimes many important details are over looked or skipped. I wish you could make these DIY videos a little more detailed so as for us to get a better picture of the build
What steps are skipped? I will not explain the basics of electronics in every video. That is why there are my electronic basics videos.
Doing a great job scott. BTW Which one is the best in features and has more functions among this Metrahit pro multi meters m242a, m242d, m242e or m253a?
As always, awesome video. But, I would simply use a microcontroller for this purpose.
Avra Mitra Same. Read actual voltage, decide in software which LED to light. You can then also add extra features like flashing LEDs to show a low voltage warning, chase them during charging, etc.
tin2001 exactly! Using a microcontroller makes it more efficient.
+1. And you could map out the non linear voltage/charge curve too.
Definitely again a good project... But I just wanted to know whether it would take care of voltage regulation due to different loads..? And how does a battery indicator works in mobiles as it always shows battery in percentage very precisely that too acurate.... And voltage regulation due to load also doesn't affect it....
Nice one :) How about a video about USB Oscilloscopes? Would be happy to see a proper video about them, if they worth even considering them, and if so, which one to go :) Thanks :)
Thank you 👍👍👍👍👍
Excellent
Hi Scott great Video, I m new to electronics what is that plastic matrix where u solder chips is it pcb? U also show it opening intro of your videos where leds are stacked and then light to great Scott
very informative.
Nice, but using arduino seems a little bit simpler, even if more expensive. Also it is worth having a switch/button in the circuit to avoid constant current draw by the display, and having it lit briefly just to check.
Thanks for sharing =D