Wow the creator of this video explained it well and he clearly understands what he is talking about. Good job. It's refreshing since a lot of other youtube videos have people who clearly don't know what they are talking about.
One thing I am sure about is that if you have a battery that coincidentally actually is the same voltage as the LED's nominal voltage then you in fact don't need a resistor. I am pretty sure the voltage from a battery doesn't randomly just spike upward in voltage and burn out the LED. It just slowly drops as it's discharged. I have done this and it doesn't hurt the LED and the LED draws the right amount of current.
GreatScott! I have a question also about what that Forssa1 guy was claiming. Was he saying you cannot connect multiple LED's in parallel using one resistor? Claims they die out etc. This is amazing since I actually have a bought LED light and took it apart and it's like a strip. So it has on the circuit board that is like a really long rectangle. It has two copper strips painted all the way up it. One positive and the other negative. It then has the 6 LED's placed across these strips which is parallel. And all they have controlling the current is 1 resistor that is before the LED's on the positive side. So this Forssa1 guy is claiming this is bad? So if one LED was to burn out then the other 5 would still run of course but he is saying they will draw too much current now and burn themselves out within time. I think of get it. As one less LED is running then technically a slightly bigger resistor should be used suddenly but it's still the same resistor which means it's allowing though that extra 20mA that has to be distributed between the other lights now. This is pretty lame that even some store bought LED strip light thing isn't made very well. With series the only reason one resistor is safe is that if an LED dies then the circuit is broken and the rest can't die. So there is some safety in a way. At the end of the day you can but 100 5mm LED's on ebay for $1. So I risk it and do parallel many times because it's easier if I just want to run some stuff off low voltage batteries and not have to use anything like a step up converter or a joule thief. Plus I notice that if you put some LED's in parallel like that light that I pulled apart the case of one randomly dying has in fact never happened to me. It's quite rare since LED's if run at their proper current rarely have any trouble and run for years and years and years. So a lot of the cases like Forssa1 guy was saying are mostly "what if" cases. As far as Forssa1 saying that "wastes power as you have to drop all the excess voltage over a single resistor". This all depends on what power source you are using. You also drop all of the excess voltage when using 1 resistor even in series. It all depends on what power source you are using. I try to make it as close as possible. So less voltage drop is needed. Doesn't matter if it's in series or parallel in this regard. I like your videos also.
To get the value of the Resistor, for LEDs in series.. For LEDs in series, forward Voltage is added, but the forward current stays the same. LED Specs.. 3.2 VF, 0.020 IF, with a 9V DC power supply. 1. Add Forward Voltage of LED's in series. 3.2V DC. 2. Subtract Total Forward voltage of LED's in series from Supply Voltage. 3.2V DC - 9V DC = 5.8V DC 3. Divide the answer you got from #2, and divide by the forward current of the LED's to get the resistor value. 5.8V DC / 0.020 = 290Ω Resistor. To Find out how much power the resistor needs to handle.. use Ohms Law. 5.8V DC^2 / 290Ω = 116mW, 290Ω Resistor. Using a 300Ω Resistor.. 5.8V DC^2 / 300Ω = 112.13mW How much current will it use, if you do want to use a 300Ω Resistor? 5.8V DC / 300Ω = 0.019333 Amps. It will be at 96.6% brightness. It looses 3.33% brightness. Using Multiple LED's in parallel is more common, because with LED's in parallel, the current is added, but the voltage stays the same.
Great video. thanks for sharing. Most ppl don't understand how hard it is to work in an advanced fashion with LED's while also balancing power efficiency and component/circuit protection requirements. You did a great job of laying down the overall dilemma's a beginner might need to consider before choosing a solution.
Nice info. I'm glad my intuition is correct, I've always made sure there was enough voltage overall and then designed for the current using either just a resistor or a simple transistor circuit or transistor/diode circuit.
Hi, I've seen some of your videos, I really enjoy them but most of times I can follow but not understand. I miself can solder a thing or too and done stuff like led lamps. But most things I can't grasp. So could you make a series, [or recommend another chanel] were you teach the VERY BASICS, like Voltage, power, resistance, or the principles of circuits for people who have cero knowledge but a lot of interest?
Diodes are introduced in pretty much all beginner level projects in the form of LEDs, but the behaviour of diodes is actually quite difficult to grasp, especially compared to resistors. For a long time I assumed LEDs to behave like any other load: a resistor. That's why I always had a very bad feeling when people looked at the forward voltage rating of an LED, and assumed that would always be the voltage drop across the LED regardless of any resistor connected to it in series. If the LED behaved like a resistor, then the fraction of the source voltage that the LED receives would be dependent on the value of the resistor connected in series. But an LED is a diode, and diodes don't obey Ohm's law. It took me a surprisingly long time to realize that.
first of all. I want to thank you. I have learned a lot. from you. in the year and 10,11 months. yours is one of the first channels I watched. when I got on this subject. I just can't get away from it. I want to learn. and you make it easy.. so thank you! and I have a question! does the watt rating of the resistor make any difference? I was going to use .5 or 1 watt resistors and diodes. its what I have. and 1/8 watt resistors for MOSFET gates. is this OK?
Hello and let me start by saying that your videos are epic! They have helped me a lot! Now I too want to ask about the 2 LEDs in series in respect to Kirchhof's 2nd law. The law states that the products of resistance times the current of all conductors must be calculated. Doesn't that mean that you need to take the voltage drop of the LED into account instead of the nominal voltage. So in the case of the 2 LEDs you need 3.2 + whatever the voltage drop (usually very small) is not 3.2*2. What do you think?
I think you might have miscalculated the resistors' power dissipation at 2:18. You'd want to calculate the power dissipated across each individual resistor, so since they're in series and they have the same value, the voltage gets divided by evenly across the two of them, giving you (5.8/2)*0.02 to find your power dissipation in an individual resistor, which gives you .058 W. Further, you are neglecting the fact that you will get a current slightly smaller than 20 mA since you have an effective resistance of 300 ohms instead of 290 ohms, but that's less important :)
I don't know why I'm watching this video I've been building LED drivers for years now... Ah yes. Now I remember I wanted to know if Scott calls it "series" or "serious" still 😅
Great Scott, you are freaking awesome. I loved making electronics but I've never did anything with ardunio and advanced parts, but Im eager to learn. Thanks for your help and work and dedication. Ive build in the past a battery bank twice but with solar power. And i know you can do better than me, so can you please make a battery bank with solar and dc charging from the wall, i would like to start there.
Looks like there are quite a few viewers not so silently correcting your grammar. Maybe they should do so in Deutsch?! Keep up the excellent videos, I enjoy them immensely.
I was in active labor and was told I couldn't eat but my boyfriend was eating Cheetos and I told him to give me some and thus proceeded to become violently ill about 36 seconds after swallowing the mouthful I ate. When the nurses came running in thinking I was pushing after seeing me heaving on the monitors they told me that your body rejects food because it stops digestion during active labor and that's why I wasn't supposed to eat. So I got to find out the hard way lol. They did also mention in case I had to get an emergency C-section and aspiration during anesthesia but didn't really focus on that as the main reason for their policy.
So for low voltage projects having leds in series is OK and not a big deal even if you have different leds with different voltage requirements. But in more advanced applications it's better to build a circuit with maintaining the current instead of the voltage. Got it. Awesome
Make one video about high power LEDs, please. :) I've been having problems to find a 3w LED driver for 3~4.2v, to use with lithium batteries, here in Brazil.
+GreatScott hi! I am so grateful to you for all the videos that allow someone who is new to understand electronic with some depth.. I would like to ask the following questions. I have 6 leds (3v; 20mA) that needs to be light up concurrently on standalone battery source (5v; 10kmAH) and last at least 2 weeks.. From this video I understand series won't work for me as I would need an input of at least 18v.. Parallel would sap 120mA thus my battery can only last me max 83 hours. Can multiplexing with an led driver help my issue?
+GreatScott! If I'm running a RGD led with a attiny85 micro controller with 3v button cell and I connect a 100 ohm resistor to all the anodes would it be fine and efficient (the red forward voltage is 2 green 3.1 and blue 3.2 with all 20 milliamperes forward current)
Servus, deine Videos sind erstklassig: sie sind detailliert und witzig zugleich -> hoher Lernfaktor! Deshalb: herzlichen Dank fuer die Muehe! Wie heisst uebrigens der verwendete Electro-track in diesem Clip? LG
I'm not getting it at 4:08. You say that you use only one resistor to limit the current of several LEDs in parallel but the schematics shows a resistor for each LED.
First measure / know what voltage you have, then measure the current through the resistor. If the current (Amperes) times the voltage (Volts) is more than what the datasheet calls "power rating" (Watts) then the resistor may burn up. You are probably fine though, the resistors shown in the video are roughly 1/4 W so, its unlikely that you will damage them with 5 Volts (unless you use resistors below 10 Ω).
Great video! Excellent and detailed explanations. I really enjoyed it and found it very useful. There is the possibility that you will make a similar one that relates to rechargeable batteries? It would be very helpful because I'm trying to do some usb battery chargers for mobile phones with various types of rechargeable battery packs. Thanks in advance!
what if I want 2 light in parallel because of the limited voltage. I want to use lithium-ion battery with 4V. How to configure it ? I tried and they died even though I gave quite high resistance than it requires. Can you help to figure it out ?
so I am a noob. am I right im this I have a 3.7v battery 3.2v led 20ma 3.7- 3.2 = 0.5v 0.5 / 0.020 = 25ohm resister? sorry if its dumb.. just trying to learn
Du sagst in der Mitte des Videos, dass eine Parallelschaltung eine Energieverschwendung wäre. Aber wenn man nur einen einzigen Widerstand für die ganze Parallelschaltung benutzt, dürfte es doch keinen Unterschied zu einer reinen Reihenschaltung geben??
MrFallout92 Wenn du nur einen Widerstand für viele LEDs nutzt, dann hast du auch nur den normalen Spannungsfall über den Widerstand wie bei einer LED. Jedoch fließt dann der n fache LED Strom durch den Widerstand, anstatt der einfache LED Strom. Daher macht es keinen Unterschied ob du ein Widerstand für viele LEDs nutzt oder ein Widerstand für jeweils eine LED. Die Verlustleistung bleibt gleich.
😎I need to simulate sunrise/sunset setting up an aquarium. I have 3w leds using a constant current driver. Possible? BTW the cc driver is store bought but maybe I can modify it
Hey Buddy can you please help...is it possible to used 1v led with 1.5 battery for a 60 day with a dailly used of 8 hrs...if yes then please help me with the process.... thanx and regards
How would I go about making an active current limiting circuit that, for example, does nothing up to 50 mA but after that, brings the output voltage down to keep the current at 50mA?
I have noticed that the resistor used in LED indicators for 220V AC appliances like mosquito repellents uses 100k resistor but according to the formula [Resistance = (Supply Voltage - LED Voltage)/LED Amps] the resistor should be 12k (approx) but why 100k is used?
it boggles my mind but i try to understand haha wanting to know how to wire up custom led tail light for a car? could you write up a basic circuit for that
My Infrared LEDs never came with ANY specifications at all =/ They where just put in a plain zip-bag with no labels whatsoever 😑 I don't know anything about them, not the wavelenght or even their size. All I know is that they're transparent and has a flat top. What should I do to figure out their ratings?
It seems like this video had no final conclusion. It seemed this video said "well you can do this, but... and you can do this, but.... or you can do this but.....". I hear a lot of information in this video that is probably useful, but I don't think is said "The best way to light 1 LED is ____, 2 ____, 3 ____, lots ______".
I want to make a toy for my daughter which uses flickering yellow LEDs, it's for a kitchen hob which the LEDs imitate the flames I have 6 holes per hob (2x hobs) but I've only got a 9v battery to power 12 off these, the spec sheet says you don't need a current limiting resistor, the forward voltage is 2.5v and requires 20mA what would be the best solution?
I have a project but can't get the resistance Part. so If I have 13x3.4=44.2 LED's and batteries 3AA at 4.5v running at 20mA the net calculator gave me a resistance of -1985 is that correct?
Sir, I've a question. I've seen in the TP4050(Li-lon Battery Charger) datasheet have standard LED for Charging status but how these are working fine with 1k resistor? Here is the datasheet www.datasheet-pdf.info/entry/TP4056. Would you please answer this - Thank you
Ok so I want to add LEDS to a RC car with a rechargeable battery I got from a portable charger as the power source, would adding a resistor be a good idea?
I've watched a lot of ur videos to get a better understanding of everything and you explain things very very well, I love taking things apart to see how they work and I love building stuff so ur videos are a great help, thanks for all ur awesome interesting videos, keep up the great work
Wait why are the voltages of the 2 led's added to get the final needed resistance of v/i, wouldn't you just add the current of the to led's to then use for ohms law. Because they require 3.2 volts, with the resistor value chosen from the equation with the voltages and current added the final voltage drop would 2.6, and the final output voltage would be 6.4. Which is 2x more voltage then they take. Without adding the voltages the final resistor value would be 145. Please help. :)
To my disappointment the LEDs I orderd, only came with the Voltage information. The Current is not noted anywhere. I just assumed 20mA, and it seems like it works well that way.
Hi i used 24vdc and 100ohm resistor connecting parallel with positive & negative and i used bulb to lit up resistor on 3 rd time switching was burnt...why it happend.
There is one Main question that dazzle me for a long time: how to identify voltage and current rates for UNKNOWN LED? Simply on my mynd comes to connect lab power supply and increase voltage untill current reaches 0.02A. But this work only with 3-5mm led's. What about >0.2W led's? I have 10W LED 220V lamp, and its failed. I taking apart and see one led with black spot - it's busted. My Unit 61E can lite up small led's in Diod Test mode (2.85volts), and he did it with other led's on lamp. But there is a problem driver gives 155Volts for 17 leds directly (no resistors on led's pcb): 155V / 17pcs = 9V (around). How 2.85Volts can light up 9V led? Current in this circle is 150mA (measured on failed led, by bypass him), and there is second problem - there is no 2835 LED with 9V / 150mA existed! Only 3.2V/150mA or 9v/100mA. So what LED should I order to replace failed??? Is there is some method to identify U/A for unknown LED?
You have probably already figured it out by now, but you should have a separate wire for your tail lamps in the wiring harness. Run an additional resistor in a value to cut the current by whatever percentage you want on the tail lamp circuit, in the proper wattage rating to handle each array. Wired in this manner, the array will be dimmer under normal circumstances and only receive full current from the brake lamp circuit when the pedal is depressed. Just include a diode on the brake lamp circuit at the lamp to prevent back feed from the tail lamp circuit. Basically, you are running two power sources in parallel with a resistor on one and a diode to separate them.
Hallo! u. Guten Tag! sorry my written german isnt too good! Have you made a lightsaber using an LED light string? using around 80 or so 5mm 3.0 - 3.2v 20ma LEDs (all wired in parallel) using 18650 LiPo or Li-ion batteries.. would a voltage regulator work? thanks i probably will get my LEDs from leading-led dot com (fair prices, nice selection, data sheets, etc) Danke
You should really try expanding into more basic videos, for beginners (how to solder, how to read shematics, etc) This was awesome, and very helpfull.
I just wanted to thank you for your great videos. I find your mix of humor and easily digested explanations to be very educational. Please keep it up!
Such comments keeps me going. Thanks a lot.
Wow the creator of this video explained it well and he clearly understands what he is talking about. Good job. It's refreshing since a lot of other youtube videos have people who clearly don't know what they are talking about.
One thing I am sure about is that if you have a battery that coincidentally actually is the same voltage as the LED's nominal voltage then you in fact don't need a resistor. I am pretty sure the voltage from a battery doesn't randomly just spike upward in voltage and burn out the LED. It just slowly drops as it's discharged.
I have done this and it doesn't hurt the LED and the LED draws the right amount of current.
David Irving That is correct.
GreatScott!
I have a question also about what that Forssa1 guy was claiming. Was he saying you cannot connect multiple LED's in parallel using one resistor? Claims they die out etc. This is amazing since I actually have a bought LED light and took it apart and it's like a strip. So it has on the circuit board that is like a really long rectangle. It has two copper strips painted all the way up it. One positive and the other negative. It then has the 6 LED's placed across these strips which is parallel.
And all they have controlling the current is 1 resistor that is before the LED's on the positive side.
So this Forssa1 guy is claiming this is bad? So if one LED was to burn out then the other 5 would still run of course but he is saying they will draw too much current now and burn themselves out within time.
I think of get it. As one less LED is running then technically a slightly bigger resistor should be used suddenly but it's still the same resistor which means it's allowing though that extra 20mA that has to be distributed between the other lights now.
This is pretty lame that even some store bought LED strip light thing isn't made very well.
With series the only reason one resistor is safe is that if an LED dies then the circuit is broken and the rest can't die. So there is some safety in a way.
At the end of the day you can but 100 5mm LED's on ebay for $1. So I risk it and do parallel many times because it's easier if I just want to run some stuff off low voltage batteries and not have to use anything like a step up converter or a joule thief.
Plus I notice that if you put some LED's in parallel like that light that I pulled apart the case of one randomly dying has in fact never happened to me. It's quite rare since LED's if run at their proper current rarely have any trouble and run for years and years and years.
So a lot of the cases like Forssa1 guy was saying are mostly "what if" cases.
As far as Forssa1 saying that "wastes power as you have to drop all the excess voltage over a single resistor".
This all depends on what power source you are using. You also drop all of the excess voltage when using 1 resistor even in series. It all depends on what power source you are using.
I try to make it as close as possible. So less voltage drop is needed. Doesn't matter if it's in series or parallel in this regard.
I like your videos also.
I always learn so much from your very well considered and practical tutorials. Highly appreciated!
To get the value of the Resistor, for LEDs in series..
For LEDs in series, forward Voltage is added, but the forward current stays the same.
LED Specs.. 3.2 VF, 0.020 IF, with a 9V DC power supply.
1. Add Forward Voltage of LED's in series.
3.2V DC.
2. Subtract Total Forward voltage of LED's in series from Supply Voltage.
3.2V DC - 9V DC = 5.8V DC
3. Divide the answer you got from #2, and divide by the forward current of the LED's to get the resistor value.
5.8V DC / 0.020 = 290Ω Resistor.
To Find out how much power the resistor needs to handle.. use Ohms Law.
5.8V DC^2 / 290Ω = 116mW, 290Ω Resistor.
Using a 300Ω Resistor..
5.8V DC^2 / 300Ω = 112.13mW
How much current will it use, if you do want to use a 300Ω Resistor?
5.8V DC / 300Ω = 0.019333 Amps. It will be at 96.6% brightness.
It looses 3.33% brightness.
Using Multiple LED's in parallel is more common, because with LED's in parallel, the current is added, but the voltage stays the same.
But I don't get very well the ending, when he talks about the LM317 :(
Great video. thanks for sharing. Most ppl don't understand how hard it is to work in an advanced fashion with LED's while also balancing power efficiency and component/circuit protection requirements. You did a great job of laying down the overall dilemma's a beginner might need to consider before choosing a solution.
Probably != Properly
"," != "."
And Serious != Series
@@marco_evertus in some countries they use the comma instead of the period as a decimal marker.
Debug.log("lol")
@@lostlakeboy4765 Log needs a capital L and you forgot the ;
"The LED would die faster than you could say 'Well shit'" 😂😂😂
I know I'm very late to this party but I literally cried laughing at that line & had to go back a ton to see the rest of the video
Nice info. I'm glad my intuition is correct, I've always made sure there was enough voltage overall and then designed for the current using either just a resistor or a simple transistor circuit or transistor/diode circuit.
I like how you said you will show us how to use an LED problably.
Hi, I've seen some of your videos, I really enjoy them but most of times I can follow but not understand. I miself can solder a thing or too and done stuff like led lamps. But most things I can't grasp. So could you make a series, [or recommend another chanel] were you teach the VERY BASICS, like Voltage, power, resistance, or the principles of circuits for people who have cero knowledge but a lot of interest?
Try reading basics or get 3rd ed (or lower) of The Art of Electronics. They stay on practice while giving enough theory to understand.
THANKS!!! Awesome Videos! I always wondered why one always requires a resistor with an LED even when the proper theoretical voltage was applied.
Diodes are introduced in pretty much all beginner level projects in the form of LEDs, but the behaviour of diodes is actually quite difficult to grasp, especially compared to resistors.
For a long time I assumed LEDs to behave like any other load: a resistor. That's why I always had a very bad feeling when people looked at the forward voltage rating of an LED, and assumed that would always be the voltage drop across the LED regardless of any resistor connected to it in series. If the LED behaved like a resistor, then the fraction of the source voltage that the LED receives would be dependent on the value of the resistor connected in series. But an LED is a diode, and diodes don't obey Ohm's law. It took me a surprisingly long time to realize that.
Woah! What a realisation! Thanks for sharing it. I was so confused about this behavior. Now I can read more about it.
Excellent explanation of current limiting!
Best video so far
first of all. I want to thank you. I have learned a lot. from you. in the year and 10,11 months. yours is one of the first channels I watched. when I got on this subject. I just can't get away from it. I want to learn. and you make it easy.. so thank you! and I have a question! does the watt rating of the resistor make any difference? I was going to use .5 or 1 watt resistors and diodes. its what I have. and 1/8 watt resistors for MOSFET gates. is this OK?
man i love your videos , can you give a little tutorial on an 8x8x8 led cube for any color leds and using the 595 shift registers ...
thx
Hello and let me start by saying that your videos are epic! They have helped me a lot! Now I too want to ask about the 2 LEDs in series in respect to Kirchhof's 2nd law.
The law states that the products of resistance times the current of all conductors must be calculated. Doesn't that mean that you need to take the voltage drop of the LED into account instead of the nominal voltage.
So in the case of the 2 LEDs you need 3.2 + whatever the voltage drop (usually very small) is not 3.2*2.
What do you think?
Your 9 look like "g" ....which threw me off for a sec... great video keep up the good work😃
Excellent basic electronics videos. Good stuff, well done. Thank You Sir!
I think you might have miscalculated the resistors' power dissipation at 2:18. You'd want to calculate the power dissipated across each individual resistor, so since they're in series and they have the same value, the voltage gets divided by evenly across the two of them, giving you (5.8/2)*0.02 to find your power dissipation in an individual resistor, which gives you .058 W.
Further, you are neglecting the fact that you will get a current slightly smaller than 20 mA since you have an effective resistance of 300 ohms instead of 290 ohms, but that's less important :)
Very Nice Explanation Sir about LED & Resistors
I don't know why I'm watching this video I've been building LED drivers for years now...
Ah yes. Now I remember I wanted to know if Scott calls it "series" or "serious" still 😅
Great Scott, you are freaking awesome. I loved making electronics but I've never did anything with ardunio and advanced parts, but Im eager to learn. Thanks for your help and work and dedication. Ive build in the past a battery bank twice but with solar power. And i know you can do better than me, so can you please make a battery bank with solar and dc charging from the wall, i would like to start there.
Looks like there are quite a few viewers not so silently correcting your grammar. Maybe they should do so in Deutsch?! Keep up the excellent videos, I enjoy them immensely.
"faster than you can say "well, $#1t" " LMAO
@@Jay-fo9gk and i thought l33t was dead lol
@GreatScott! you mention that you were build a more efficient const current source in a future video - did you? thanks :)
WOW!! Your videos are awesome a lot of good information to a beginner in electronics, like me.
When you get a chance, could you go over in detail how to characterize LEDs to find the most efficient voltage/current to drive them?
I was in active labor and was told I couldn't eat but my boyfriend was eating Cheetos and I told him to give me some and thus proceeded to become violently ill about 36 seconds after swallowing the mouthful I ate. When the nurses came running in thinking I was pushing after seeing me heaving on the monitors they told me that your body rejects food because it stops digestion during active labor and that's why I wasn't supposed to eat. So I got to find out the hard way lol. They did also mention in case I had to get an emergency C-section and aspiration during anesthesia but didn't really focus on that as the main reason for their policy.
So for low voltage projects having leds in series is OK and not a big deal even if you have different leds with different voltage requirements. But in more advanced applications it's better to build a circuit with maintaining the current instead of the voltage. Got it. Awesome
In your parallel array of LEDs, I think if you matched each resistor specifically to each LED, then there would be no issues with your design.
@ 2:23 you say that since 0.116W
I think i'll come back to this series once i'm a bit more smarter.. (currently in grade 10, gonna take another course of computer science in grade 11)
Make one video about high power LEDs, please. :) I've been having problems to find a 3w LED driver for 3~4.2v, to use with lithium batteries, here in Brazil.
love your videos, keep up the nice work scott!
your videos are awesome. There should be more viewers.
How did you built your led slogan/sign? One circuit or more? How did you design it, try and error?
+GreatScott hi!
I am so grateful to you for all the videos that allow someone who is new to understand electronic with some depth..
I would like to ask the following questions.
I have 6 leds (3v; 20mA) that needs to be light up concurrently on standalone battery source (5v; 10kmAH) and last at least 2 weeks..
From this video I understand series won't work for me as I would need an input of at least 18v.. Parallel would sap 120mA thus my battery can only last me max 83 hours.
Can multiplexing with an led driver help my issue?
+xzeionax A simple PWM dimmer would create the same effect as multiplexing and is easier to make. Try a 555 timer circuit.
+GreatScott! Thank you for your prompt reply!! I am checking out your video on pwm dimming..!!
+GreatScott! If I'm running a RGD led with a attiny85 micro controller with 3v button cell and I connect a 100 ohm resistor to all the anodes would it be fine and efficient (the red forward voltage is 2 green 3.1 and blue 3.2 with all 20 milliamperes forward current)
cool tutorial(s), indeed... yet, it's 'properly' not 'probably' ...or maybe I need to get rid of excess earwax ^^
Are you series?
Really?!
okay so now i know how to probably use an LED ^^
Servus, deine Videos sind erstklassig: sie sind detailliert und witzig zugleich -> hoher Lernfaktor! Deshalb: herzlichen Dank fuer die Muehe!
Wie heisst uebrigens der verwendete Electro-track in diesem Clip?
LG
@GreatScott! Thanks vor the Video waiting for the next one 😁 maybe using attiny without much conponents?
Can you please explain what U is in your calculations? Thx.
Voltage
Great Scott!
I'm not getting it at 4:08. You say that you use only one resistor to limit the current of several LEDs in parallel but the schematics shows a resistor for each LED.
do resistors get hot? is it normal?
Yes. That is the only thing they can do.
+GreatScott! poor resistors.... :D
Chardx PerfectStranger
yes read about power rating
First measure / know what voltage you have, then measure the current through the resistor.
If the current (Amperes) times the voltage (Volts) is more than what the datasheet calls "power rating" (Watts) then the resistor may burn up.
You are probably fine though, the resistors shown in the video are roughly 1/4 W so, its unlikely that you will damage them with 5 Volts (unless you use resistors below 10 Ω).
That's one might hot resistor you got there....
if i connect blue and red led without resistor, blue led turn always off.. why?
thats awensome!! and i tryet this cool experiment and its done with a arduino uno wow thats really cool
is it possible to make series of different color led, ie red and blue? different forward voltage. thanks
When i was a kid i always burned my hands while playing with 9v battery and 3.2 volt leds
Very well explained, thanks
What resistors would you use for three 3v white led’s using 12v in a series ?
Great video!
Excellent and detailed explanations. I really enjoyed it and found it very useful.
There is the possibility that you will make a similar one that relates to rechargeable batteries?
It would be very helpful because I'm trying to do some usb battery chargers for mobile phones with various types of rechargeable battery packs.
Thanks in advance!
TheMagicOfGabriel One of my next projects involves NiMh rechargeable batteries. Stay tuned!
GreatScott! Thanks !
What tools do you use in your videos, and would you buy them again?
What basic stuff do I need, which works fine and wouldn't cost that much?
Good question. I will make a video about it soon.
what if I want 2 light in parallel because of the limited voltage. I want to use lithium-ion battery with 4V. How to configure it ? I tried and they died even though I gave quite high resistance than it requires. Can you help to figure it out ?
Do you still need a resistor if you use a constant current source?
If your source is set to the proper current, then no.
Hi .... wieso machst du die Videos auch nicht auf deutsch?
so I am a noob. am I right im this
I have a 3.7v battery
3.2v led 20ma
3.7- 3.2 = 0.5v
0.5 / 0.020 = 25ohm resister? sorry if its dumb.. just trying to learn
If I got LED's from eBay, and they don't tell me the ideal current, what can I do to get this value?
Is there a tri-color led bulb smaller than 5mm (like 2 or 3mm)? I'm trying to create a Led matrix board with more resolution.
Why the diode lights up when you put it via multimeter on diode position (it will sign 2.4 -2.6 volts on the multimeter)?
Du sagst in der Mitte des Videos, dass eine Parallelschaltung eine Energieverschwendung wäre. Aber wenn man nur einen einzigen Widerstand für die ganze Parallelschaltung benutzt, dürfte es doch keinen Unterschied zu einer reinen Reihenschaltung geben??
MrFallout92 Wenn du nur einen Widerstand für viele LEDs nutzt, dann hast du auch nur den normalen Spannungsfall über den Widerstand wie bei einer LED. Jedoch fließt dann der n fache LED Strom durch den Widerstand, anstatt der einfache LED Strom. Daher macht es keinen Unterschied ob du ein Widerstand für viele LEDs nutzt oder ein Widerstand für jeweils eine LED. Die Verlustleistung bleibt gleich.
😎I need to simulate sunrise/sunset setting up an aquarium. I have 3w leds using a constant current driver. Possible?
BTW the cc driver is store bought but maybe I can modify it
Hey Buddy can you please help...is it possible to used 1v led with 1.5 battery for a 60 day with a dailly used of 8 hrs...if yes then please help me with the process.... thanx and regards
How would I go about making an active current limiting circuit that, for example, does nothing up to 50 mA but after that, brings the output voltage down to keep the current at 50mA?
I have noticed that the resistor used in LED indicators for 220V AC appliances like mosquito repellents uses 100k resistor but according to the formula [Resistance = (Supply Voltage - LED Voltage)/LED Amps] the resistor should be 12k (approx) but why 100k is used?
it boggles my mind but i try to understand haha wanting to know how to wire up custom led tail light for a car? could you write up a basic circuit for that
If you're lazy, there are sites that you can use to calculate the value of series resistors including the proper wiring for led's.
rene kenshin Link?
Just type in google led calculator
My Infrared LEDs never came with ANY specifications at all =/ They where just put in a plain zip-bag with no labels whatsoever 😑 I don't know anything about them, not the wavelenght or even their size. All I know is that they're transparent and has a flat top.
What should I do to figure out their ratings?
It seems like this video had no final conclusion. It seemed this video said "well you can do this, but... and you can do this, but.... or you can do this but.....". I hear a lot of information in this video that is probably useful, but I don't think is said "The best way to light 1 LED is ____, 2 ____, 3 ____, lots ______".
what size of resistors do I need to connect 3 white led bulbs to a usb port
I want to make a toy for my daughter which uses flickering yellow LEDs, it's for a kitchen hob which the LEDs imitate the flames I have 6 holes per hob (2x hobs) but I've only got a 9v battery to power 12 off these, the spec sheet says you don't need a current limiting resistor, the forward voltage is 2.5v and requires 20mA what would be the best solution?
1:15 "Well Shit..." Omg! I laughed my balls off at this!
what if you want to mount the led's that are in series in separate locations spaced out by connecting wire? would that change anything?
That was an awesome video!
This review is very useful.
I have a project but can't get the resistance Part. so If I have 13x3.4=44.2 LED's and batteries 3AA at 4.5v running at 20mA the net calculator gave me a resistance of -1985 is that correct?
Sir, I've a question. I've seen in the TP4050(Li-lon Battery Charger) datasheet have standard LED for Charging status but how these are working fine with 1k resistor? Here is the datasheet www.datasheet-pdf.info/entry/TP4056. Would you please answer this - Thank you
Does that apply to zener diodes as s well?
May you make a video on 555 timer?
Ok so I want to add LEDS to a RC car with a rechargeable battery I got from a portable charger as the power source, would adding a resistor be a good idea?
I've watched a lot of ur videos to get a better understanding of everything and you explain things very very well, I love taking things apart to see how they work and I love building stuff so ur videos are a great help, thanks for all ur awesome interesting videos, keep up the great work
Wait why are the voltages of the 2 led's added to get the final needed resistance of v/i, wouldn't you just add the current of the to led's to then use for ohms law. Because they require 3.2 volts, with the resistor value chosen from the equation with the voltages and current added the final voltage drop would 2.6, and the final output voltage would be 6.4. Which is 2x more voltage then they take. Without adding the voltages the final resistor value would be 145. Please help. :)
isn't there any use of source current, i mean current which we draw from the supply
how did you make a power supply from an computer psu?
To my disappointment the LEDs I orderd, only came with the Voltage information. The Current is not noted anywhere. I just assumed 20mA, and it seems like it works well that way.
Hi i used 24vdc and 100ohm resistor connecting parallel with positive & negative and i used bulb to lit up resistor on 3 rd time switching was burnt...why it happend.
well shit! haha
Brilliant videos. keep up the good work.
I enjouy your tutorials , however you are very fast.
do x0.5 speed
Spoder Man lol thanks
Best things to watch
Added to my fav vids
There is one Main question that dazzle me for a long time: how to identify voltage and current rates for UNKNOWN LED?
Simply on my mynd comes to connect lab power supply and increase voltage untill current reaches 0.02A. But this work only with 3-5mm led's. What about >0.2W led's?
I have 10W LED 220V lamp, and its failed. I taking apart and see one led with black spot - it's busted. My Unit 61E can lite up small led's in Diod Test mode (2.85volts), and he did it with other led's on lamp. But there is a problem driver gives 155Volts for 17 leds directly (no resistors on led's pcb): 155V / 17pcs = 9V (around). How 2.85Volts can light up 9V led?
Current in this circle is 150mA (measured on failed led, by bypass him), and there is second problem - there is no 2835 LED with 9V / 150mA existed! Only 3.2V/150mA or 9v/100mA. So what LED should I order to replace failed???
Is there is some method to identify U/A for unknown LED?
I need to power 7 in series 3.4 volt RGB blinking LEDS by 12 volt power source, what resistor do I need?
So I wired my custom led tail light and it super bright is there a way to dim it while keeping the brightness when I brake?
You have probably already figured it out by now, but you should have a separate wire for your tail lamps in the wiring harness. Run an additional resistor in a value to cut the current by whatever percentage you want on the tail lamp circuit, in the proper wattage rating to handle each array. Wired in this manner, the array will be dimmer under normal circumstances and only receive full current from the brake lamp circuit when the pedal is depressed. Just include a diode on the brake lamp circuit at the lamp to prevent back feed from the tail lamp circuit. Basically, you are running two power sources in parallel with a resistor on one and a diode to separate them.
Is there like a kit with all the wires and board I can order?
just buy a breadboard and some jumper wires or if you are new to electronics buy an arduino kit
0,125 is 1/8W not 1/4W .. or did I misunderstand?
Hallo! u. Guten Tag! sorry my written german isnt too good! Have you made a lightsaber using an LED light string? using around 80 or so 5mm 3.0 - 3.2v 20ma LEDs (all wired in parallel) using 18650 LiPo or Li-ion batteries.. would a voltage regulator work? thanks i probably will get my LEDs from leading-led dot com (fair prices, nice selection, data sheets, etc) Danke
Very well undetstood
what if I want to for example use 1 LED with 20ma and 1 with 10ma. what should I do?
Use 1 resistor per LED. Figure out the values using the formula outlined in the video.
What if the current change? I need to adapt a 12v switchin power supply to 8,4v to charge a camera
hi! hast du auch ein video zum eigenbau netzteil bei 3:33 min?
5igi3lue th-cam.com/video/QoGnOoTICGY/w-d-xo.html
GreatScott! hatte ich inzwischen gefunden... find ich eine total gute idee!!! vielen dank! :)