## Simple LED Tubelight Circuit - Explained Comprehensively

Explained in a very lucid style and through a schematic the complete construction of a LED light tube circuit which can be operated directly from the 230V AC mains of your domestic supply. This will not only save electric power but also help curb the global warming issue.

The simple construction of an LED light tube discussed here will not only save electric power but also if used in every house will help reduce the ever increasing global warming effects.

Introduction

Today we are all aware regarding the bad effects of global warming and how it’s gripping our only planet day after day. But for this we ourselves are to be blamed. You may be thinking how a common person can contribute to help solve the problem. Well look around you, yeah, it’s the lights that we are using presently generate quite an appreciable amount of heat to add to the global warming effect. CFLs are considered to be quite efficient, but they too release quite a bit of heat. The issue can be very easily solved simply by transforming our heat producing lights into the "cool"  white LED lights. We will learn in this article how simple it is to build a LED light tube that can easily replace your existing "hot" fluorescent tube lights!

You will require the following things for the construction:

One 36 inches long, 2 inches in diameter white PVC pipe,
150 Nos. White LEDs (5mm),
4 nos. 1N4007 diodes,
3 nos. 100 Ohms resistors,

1no. 1M resistor, 1/4 W,

1no. Capacitor 105/400V, Polyester,
14/36 Wire for connections,
Soldering iron, solder wire etc.

How to Build a Homemade LED Tubelight Circuit

The construction of this circuit is carried out through the following simple procedures:

Cut the PVC pipe lengthwise into half.
Drill equally distributed LED size holes over the entire area of the two halves of PVC pipes.
As shown in the diagrams just fix all the LEDS throughout the pipe. Be sure to keep the position of the polarity of all the LEDs in the same orientation,
Cut and bend the LED leads so that the leads touch each other side by side.
Make 3 series of 50 LEDS each by soldering the joints. Make sure that each series comprises the given resistor of 470 Ohms.
Connect the 3 series LEDs groups in parallel by joining their positive and negative leads together through flexible wires.
Make a bridge configuration rectifier by joining the 4 diodes together, and connect the relevant points to the LEDs and to a 2 pin mains cord, as shown in the figure.

How to Test it?

Testing this LED tube light circuit is probably the simplest part of the whole operation; it is done through the following simple steps:

After finishing the construction procedure as described above, just plug in the 2 pin plug into the mains socket (be extremely careful as the whole circuit may contain leakage currents).
Instantly all the LEDS should come ON giving a  dazzling effect.
If any of the series is dead or not glowing, switch OFF the power and check for the LEDs connected with wrong polarity.
Glue all the LEDs so that they may not come out of the holes I which they are inserted.
Finally join the two halves of the PVC pipes with the LEDS, either by tying them or gluing them together with cynoacralite bond.
Close the two open ends of the tube appropriately.
This concludes the construction of the LED light tube circuit.
For optimum performance it would better to hang the unit from the ceiling so that the light is distributed equally.

Here's a 50 LED Tube Light made by Merley, for your viewing pleasure:

LED string light made by Mr.Bibin Edmond using the explained capacitive power supply.

Here's the image of the simple capacitive PS circuit used for lighting the above string LED light.....
courtesy: Bibin Edmond

#### hitman

Hi Friends, Welcome to my site, a place where you will discover a massive collection of electronic circuit ideas, mostly requested by the dedicated readers and exclusively designed by me for their customized application needs. I have posted more than 1100 circuit designs in this site, if you have a personalized circuit requirement you may feel free to request it through the comment box, if it seems feasible to me then surely you may find it published here with your credentials attached in the post, thanks and please keep reading>

1. Hi Swagatam,

I had not come across such a useful site in my life.
This will help most of the students.
Need some details like total watts consumed/hour.

Sagar B

1. Hi Sagar,

You are welcome!

The power is 5 watts per string, multiply it with the total number of strings included in the circuit.

Regards.

2. Hi Swagatam,

My name is saty, I have seen your LED Circuit with BD140 with 24 LEDs with 6v 4AH battery with tranformerless circuit 9v zener(1 watt) is used in that circuit. It is working fine.

How many LEDs can be parallelly added to the above/mentioned circuit. (I think BD140 can withstand upto 1.5A current disipation so my gess is 60 to 72 LEDS can be connected to the circuits. Please adive or help me in this.

Thanks and Regards
S.Sathappan

3. Hi Saty,

Thanks very much for making the circuit successfully.
Though BD140 can handle upto 1.5A, it won't be a good idea to load it to it's full capacity.
Loading it upto 1Amp is quite OK, for more power probably we can use a AD149 or similar transistor in place of BD140.

Regards.

Keeping the exisiting circuit can i connect 48 LEDs with BD140, tranformerless power supply wwith 9v zener with 4AH battery.

Another question is for High voltage protection to the battery 470 ohms can be connected series with D2 diode. Will it protect the battery.

Thanks and Regards
Saty

5. Yes, you may connect them.... 48 LEDs should consume not more than 250mA, so that's OK.
470 Ohms is also OK for trickle charging the battery and for high voltage protection.

6. sorry 48 leds will consume 500mA, still not a problem.

Keeping AD149 can i connect 150 LEDs, i think it will withstand 3.5A current, but can i use the tramformerless circuit (what max current can be used for tranformerless)? if not can i use the tranformer, Please let me know if tranformer what amps and what volt tranformer. Any change in the exising circuit, Awaiting your reply.
Thanks and Regards
Saty

8. AD 149 will be able to control 150 LEDs but your battery won't, it will probably last only for a few minutes. You will need to increase the AH.... or the voltage of the battery and the LED series.

A transformer will be required if AD 149 is used, a 500mA, 0-12V would do.
Regards.

1. using AD149 with 12V transformer with 6V/4AH battery what change in the circuit?
2. can i connect 2 leds in series with what resistor to be used instead 22ohms and how many can be parelled? (for 150 LED) will it work?
3. Sorry to trouble you if possible post the diagram for 150 LED with the same circuit with changes.
4. Can't change the battery to 12V/7AH, since its size is more and it cannot fit in the cabinbox. Please keep 6V/4AH tell me how it works for 150 LEDs and duration?(minutes)

Thanks and Regards
Saty

10. Hi Saty,

I've posted the diagram here, please check it:

Regards.

11. Thanks for the diagram.

I will implement this diagram and let you know the status.

One more help.

I need sine wave inverter for home (for 3 tubelight, 3 ceiling fan and 1 fridge(double door fridge). what capcity inverter? (like 3kva), what battery? and what is the circuit you refer and how much it will appromately cost in indian rupees. Awaiting your reply.

Thanks and Regards
Saty

12. A 3 KVA inverter will be huge, at present I don't have sufficient knowledge regarding the construction of such a massive inverter, so cannot help you with it.
Regards.

13. for (3 tubelight, 3 fan and 1 fridge) what is the VA or KVA required inverter to be used. Pls suggest.

1. 48 LEDs with BD140 with 6V/4AH battery. How many hours LED will bright?(~ hours)
2. 150 LEDs with AD149 with 6V/4AH battery. How long it works? (~hours)
3. How to calculate the hours in general for the above circuit?

Awaiting your reply. Where you placed, can i call u if needed. if so pls give your number and place.

Soo much interested with your blog.

Thanks for the help.

Regards
Saty

14. Hi Saty,
Thanks for liking my blog :-)

Ideally you should multiply 1.5 by the total wattage of the load to get the required VA of the inverter.

Battery back up for a particular battery may be calculated by using the following formula:

However the above result will be for an super ideal battery, normally it will be much much lower than the above result.

Regards.

1. 48 LEDs with BD140 with 6V/4AH battery - (i.e 48 * 0.02(20ma)) Backuptime=4/0.96=4.16 - approx 4Hrs and 16 mins

2. 150 LEDs with AD149 with 6V/4AH battery - (i.e 150 * 0.02(20ma)) backuptime=4/3=1.3 - approx 1hrs and 30 mins

is that above calculation right?
Could you pls give your location and phone number?

Thanks and Regards
Saty

16. That's correct, but it's for an ideal battery with 100% efficiency, normally batteries don't provide even 80% efficiency and it further deteriorates with age of the battery.

So divide the above result with 1.5 approx, that should give a fairly close value.

Regards

Have a nice day.

Could you pls give your location and phone number?

Thanks and Regards
Saty

18. How to get the correct resistor value to White LED's if 6v/9v/12 supply.

Please let me know how to calulate the resistor value with an example in series and parllel connection.

Thanks and Regards
Saty

19. Use Ohms law, R = U/I, you will directly get the resistor value in Ohms.

Due to busy schedule, phone conversation would be difficult, sorry!
Feel free to interact with me here.

I'm based in Mumbai.

Regards.

for example -> tranformer=6v/500ma, I=current

Can you give me an example r=v/i -> r=6/which current to be used tranformer current as 500ma or LED current as 20ma. Please explain me with an example so that i can understand clearly.

Thanks for the location. I'm based on chennai. if any visit to chennai pls let me know we will meet in person.
No problem i will keep in touch in this.

Thanks and Regards
Saty

21. Hi Saty,

U is the supply voltage, I is the LED current which may be anywhere between 20 and 40 mA.
So now you can easily calculate "R"

If I get an opportunity to visit Chennai any day, I'll surely let you know.

Thanks!

1. 48 LEDs with BD140 with 6V/4AH battery - replacing the tranformerless circuit to tranformer what volt tranformer to be used? 6/9/12-500MA and what is the change in the circuit after the bridge circuit??
if 6v - no change in the circuit
9v - what change??
12v - what change??
is it zener diode required?
pls if possible draw the power supply diagram (for all the above voltages as seperate diagram)and just show the connection to the LED circuits.

Thanks and regards
Saty

23. Hi,Saty

6v/500mA will be OK, no change is required after the bridge/cap network.
9 and 12V will be too high for the battery, so surely not recommended.

Thanks and Regards.

1. 6V is ok

2. 9 and 12V 500MA tranformer is too high for the battery (got ur point), but can we use resistor to drop the voltage or if needed zener diode can be used or any alternative components can be used? if so how to calculate the resistor value and how to be connected in the circuit, Pls show me diagram using 9V and 12V powersupply which is drop to 6V and connected to battery circuit (i.e the LED circuit).

Thanks and regards
Saty

25. Calculations will not be required for regulating voltage levels, it can be simply done by using voltage regulator ICs like 7805 (for 5 volts), 7806 (for 6 v) 7812, 7824 etc.... zener diodes cannot support more than 1 watt and tend to dissipate heat so it is recommended only for low current applications, not for high current as in our circuit.
Check the datasheet of the above ICs you will understand how to use them.
Regards

26. Thanks for the help. I will implement this and let you know if any thing required.

Regards
Saty

2. hi, how many LED strip can add to this circuits?

1. Not more than what is shown in the diagram.

2. Hi sir,
I am ajeesh,4 last two days i was going thru ur block n ur replies,u r actualy doing a great job sir.can u tel me weather i can use ur led tubes for three phase supply,if not tell me what should I do(i am having 3 phase at home).what all changes should I make. . .kindly reply. . .

3. Hi Swagatam,

is this circuit will work to a 110Vac?

1. Hi,

Yes it will work after doing the following modifications:

The series will need to be reduced to 25 nos. for each of the channels and the input capacitor should be made into 2uF/250V

Regards.

2. thanks... your an angel :)

4. hey, thanks for the useful circuit i will try it, but what the least or minimum LEDs for this circuit 150 LEDs is hardly to attached in PVC pipes, so please give the least quantity of led & for further changes in circuit.. Thanks again....

1. Hi,

You may reduce the number of LEDs as per your needs, the rest of the circuit remains the same. Use the last circuit which is the safest.

Regards.

5. Hi Swagatam,

can i use 105/630V for the capacitor?

Regards

1. will do , you may try it.

6. Hi,

in this circuit... can i use 50pcs of LED?

Thanks

1. yes, no problems with 50 numbers of LEDs, go ahead.

7. Hi swagatam,

that is awesome work you did. I would request you for one thing. If you have done this project, I would greatly appreciate if can record a demo video of illuminating this led tube light against a fluorescent tube light so we can have a fair idea what it is like.. if you already have a video please add url. thanks..

1. Hi,

Thanks very much.

I had constructed it a long time ago, and the circuit is in a bad shape now, and many of the LEDs have been removed for some other purposes, but surely if I get time to fix the prototype, I'll record the results this time and present it here.

Regards.

8. hey i am yash i want to know the basic circuit of tesla coil to built if u know please help me out with perfect map of this waiting for reply

1. Hi Yash,

Presently I don't have the exact winding data of a tesla coil, but if you explain me about how you built it then probably I would try to understand and troubleshoot the circuit.

You can post it to hitman2008@live.in

9. Hi swagatam,
I'm Niro. I made this and it's working nicely. Dear Thanks for the posting good, useful and “working” circuits. Dear if I change this circuit to 10 Led, 20 Led, 30 Led or 40 Led, what are the changes I want to do ?

1. Hi Niro,
Thanks very much!

You may reduce the input capacitor to 0.5uF/400V, a 474/400V cap will do.

10. Mr.swagatam, Niro here.
This circuit worked nicely, but after five days leds are not lightning. I checked all the leds and it's all are working. And I put all the parts in correct value. What is the problem dear...?

1. Mr.Niro,

Check the voltage across the bridge, if it doesn't show any voltage, your capacitor might be blown and if the voltage is present, check the LED resistors, they might be burnt...

11. hi swagatham

how many lumens it can produce?

1. Hi Sandy,

I haven't checked it, but I assume it to be well above 2000lm

12. ohh fine...

that mean it s almost equall to 36w flourcent tube ?

what type of leds to be used and what will be the cost?

1. Might be, can't confirm as I did not measure it practically.....the LED are 5mm high efficiency white lEDs, 3.3V/30mA, Total cost of the unit would be approx. Rs.200/- or \$4.

13. Hello sir...I am kamlesh...I couldn't find any word (except sir) which will give you more respect...
I am a new visitor of this site..and i am amazed...I will start with this LED tube light..and hope for your precious help if i am struck...

many many thanks sir...

1. Welcome to my blog Kamlesh.

Best wishes to you!!

14. what adjustments will i have to do if i need only 50 LEDs

1. Nothing, just eliminate the other two LED channels and let only one channel remain.

2. hi....
thank you & i made the circuit and worked fine with 50 leds..... can you please give some detailed explanation about the circuit design like
1>the why the resistance & capacitance are set to so and so value.
2>how can the same supply circuit work for 50 as well as for 150 LEDs????

3. Actually 50 LEDs will produce more light, and the intensity will go on decreasing as the number of LEDs are increased, so the results are not similar.

15. i actually wanted a circuit which can vary the intensity of the LED(i am making a N-scale town so i need the LED as street light) so which POT do you recommend and where should i connect it????

1. In the above circuit, this may be implemented simply by adding a pot in series with the positive line from the bridge rectifier, a 2K, 1 watt value may be tried initially.

2. hi there....thanks for the reply
i dont know what happened, but the above circuit with 50 LEDs worked for a day generated a lot of heat and next day stopped working(i dint add the POT yet). i tested it with a multimeter, the 1M resistor isn't showing any resistance on the meter(maybe its fried) AND some LEDs have low light intensity(is it due to low no. of LEDs????)
any suggestions OR modifications???

3. A 1M resistor can never fry, because the value is too high to get fried, but if its showing a short then probably that's the only reason for the damages.

By the way did you connect the MOV and the zener etc, as suggested in the article??

4. you were right about the resistor... it never fried. how much volts is supposed to be supplied to the LEDs? 250V? coz thats what is showing on the multimeter.
everything on the supply circuit is fine(except for capacitor i dint check them) still dont know where the problem is.... will try the other curcuit with 100 LEDs this time. thanks and will let you know!!!
is there a quicker way to contact you??? i need the circuit working real quick for some important reason. you can contact me at electro_nik_54@hotmail.com

5. Connect a flashlight bulb at the output, if it lights dimly and if the voltage drops to 3 v, means the circuit is OK, a blown bulb would mean the cap is not OK and the output is directly connected with the mains.

16. Hi Swagatham,

This is Somasekhar, Thank you so much for providing very very usefull information about "How to Build a Homemade LED Tube Light" .

Yesterday I bought all the raw material to build a LED tube light , But I got a doubt in opne point .

In the above procedure you have mentioned about
"Make 3 series of 50 LEDS each by soldering the joints. Make sure that each series comprises the given resistor of 470 Ohms"

But you have mentioned to connect 3 nos, 100 Ohms resistor to each series in the diagram.

Can you please expalin me, I am an Natural science guy with out basis knowledge of electronics.

Regards,
SOma.

1. Thank you very much Somasekhar,

Actually 100 Ohm resistors will produce more light from the LEDs while 470 will make it less bright, so you may choose any intermediate value for optimal light as per your preference.

Regards

17. Hi Swagatam
this is Rajib.

I want to make this home made led tube light but it should have a automatic battery which will stop charging after charging is completed ....and the intensity to be controlled by an ir remote....can I use your circuit with these mentioned features?

with regards
Rajib

1. Hi Rajib,

Yes you can use the above circuits, the second circuit which incorporates a zener diode looks more reliable to me so you may use the second circuit from top for your project.

Regards.

18. hi Swagatam I want to make an led emergency light with automatic battery disconnection and intensity control with remote .can i proceed with your circuit?
Regards
Rajib

1. Hi Rajib,

19. Hi Swag,
Good Work, Appreciate your willingness to share and help.
Will try the tube light circuit in the near future. stumbled on you as i was searching the web for eco stuff....like led lights, solar panels etc.
Im an aircraft engg. and if you ever need any help with mech stuff like cars/bikes....give me a shout.
Ahh...almost forgot the reason why i was writing to you in the first place.....
Have you made any videos / youtube......cause that will be just awesome!.....and bet you, youll get quite a few hits!
Val.
valentineair@gmail.com

1. Hi Val,

You are most welcome...it would be great to have a mech eng's expertise here too.
Yes definitely I'll consider regarding making and posting videos also, that would create better impact and improve the blog's popularity... appreciate it.

Best Regards.

20. Hi!
I am very to see your blog and I got it what I couldnt find any other sites. I thank you very much. Your response to every question here tell that Swagatam is an expert....

Safri.

1. Thanks Safri...you are most welcome.

21. Hi,
If I want to make this circuit with 50 LEDs what modifications will I have to do?
And what about the resistors connected to each 50 LED series?
what are the changes I have to do to resistors and its value?

Can you tell me what is the most reliable circuit in the above 3 circuits which can run for years without any problems?

What are the steps have to take to make it reliable and safe?

Thanking you.

Safri

1. For 50 LEDs just eliminate the remaining two channels, no other mods are required.

According to me the second circuit with the 200 volt zener is better as it will not allow the voltage to go over the 200 mark.

The addition of the zener should make it reliable....however I have not tested it for longer periods of time so cannot say much...

Regards.

2. Thank you very much Swagatam. You have a good heart to spend your time to help others. Wish you for a wonderful present and future.

I am a student of electronics and telecommunication from Sri Lanka if I need any help can I ask you?

Best regards,

Safri.

3. You are welcome Safri!

4. Hi,
I couldn't find the zener 200v,1w. Are there any code number for this Zener diode? If I couldn't find 200v zener and If I have Zener with another value how can I connect them to get this value? ( please consider W also)

For the time being you can make the circuit without the zener diode also...zener diode is for extreme safety.
Initially use a 474/400 capacitor at the input, this will make the LEDs more safe.

22. Hi Val,

This is Soma here,

I am fond of creatings things which makes me very much happy.

Can youplease let me know how we can make Quad bike for personal use using old mechanical spares or new spares.

Soma

23. HI Swagatham Sir,

one more doubt regarding the LED tube light project in the diagram I am unable to concluede, How I can connect the below things

1) LED's -- How we have to connect Positive - Positive ,
Negative - negative

Or else we have to connect postive - negative as per the diagram.

2) Ho to find the Positive , Negative terminals for 1N4007 diodes.

3) Ho to find the Positive , Negative terminals for 100 Ohms resistors,

4)Ho to find the Positive , Negative terminals for Capacitor 105/400V, Polyester,

In the above diagrams also there is no signs of Positive and negative.

Soma

1. Hi Soma,

The longer lead of LED is positive and the shorter lead is the negative.
Connect longer lead of one led with the shorter lead of the next led and make a chain of 50 LED's.

The banded side of the diode corresponds to the vertical bar shown in the diode symbol in the diagram.

Resistors can be connected anyway round they don't have polarity.

105 capacitor in this diagram is also non polar and may be connected anyway round.

24. HI Swagatham Sir,

Thanks you so much for your help

Regards,
Soma

1. you are welcome.

25. Hi Swagatham sir,

I am unable to find 105/250V capacitor, Shall I use 100/250V capacitor.

And also I am uanble to find 22 ohms 1 watt resistor, Shall I use 3900 Ohms resistor

Regards,
Soma.

1. Hi Soma,

All your values are hugely different and nowhere close to the required values, so I am afraid you cannot use them, they won't work...

Regards.

26. Swagatama really appreciate you for sharing your valuable designs...i connected 50 leds to your circuit but the flickering would not stop. Any suggestions ?

Regards

1. Thanks Mayya,

Try connecting a 10uF/100V or similar cap across the positive and negative supply rails, this would filter out the supply and provide smooth illumination.

27. helo sir i like your cicuit very much but i want to know that can these leds produce light equal to 25watt flouresent energy saver bulb

No Not 25 watt, it might reach up to a 11 watt CFL

29. Hu Swagatama,

First, thanks for all your work. I'm looking at your site in the last 3 hours and I can't stop!

In the last picture (with 22R x 1W resistor at input) the capacitor near the bridge is 105 x 250V (1ÂµF x 250V)?

Also, here the AC mains is normally 127V (min is 116V and max 132V).

You said that the circuit works on 110V, changing the input capacitor to a 2uF x 250V, and putting only 25 leds in each string.

Questions:

1) To use with 110V, the second capacitor (near the bridge), has also to be changed to a 2uF x 250V?

2) Here is almost impossible to find 2uF capacitor. Can I use a 2.2uF x 250V? (2.2uF is commercial value here).

3) Is there any way to put more leds using 110V (more paralel strings, perhaps)?

4) What the limiting resistor values to use in 110V?

Sorry for so many questions and my bad english.

Regards from Rio de Janeiro - Brasil.

1. Hi Plautz,

Thanks very much!! you are most welcome here....keep rocking.

Actually a 1uF/250V would also work at the input.

The output cap is not critical at all, so a 1uF/250V would work there as well.

You can put 110/3.5 = 30 LEDs in series with a 100 Ohm resistor, and go on adding more such series in parallel, until the light doesn't look too dim.

Regards.

30. Hi Swagatham Sir,

I have one query, Can you please clarify me .

Instead of using 150 LEDS, can I use 155 LEDS with the same components ( as mentioned in the last circuit diagram).

Regards,
Soma.

1. Hi Soma,

Yes 155 LEDs can be accommodated in the given design.

Regards.

2. Thanks you so much Sir,

Regards,
Soma

and i have two question
1. what is the quality of this circuit?
2. can i use it professionally?

1. I've not tested this for longer periods of time so cannot confirm it's reliability, however if adequate protection measures are included, the unit can be trusted I think....

2. Hi Swagatham Sir,

The End terminals we have to place positive in positive socket only (in switch board socket) and negative in negative only?

Or else we can keep the terminals either way in swith board socket?

Can you please let us know.

Thank you so much Sir in Advance

Regards,
Soma.

3. Hi Soma,

You may connect it any way round, polarity does not matter because it's AC...

32. Please tell me the second capacitor (output capacitor ) is non polarity or polarity capacitor.

1. It's NON-POLAR same as the input capcitor

33. thank you
but how out put voltage is ripple free. by non polar capacitor

1. Actually it was introduced for arresting the initial switch ON surge and not as a filter, however it seems the idea is not so useful so it may be eliminated.

34. I wish to use a series of LED's (maybe 150 or more) to illuminate a room or a walkway just when there is power cut. The power should be from a 12v or a 6v battery which ever is suitable.

When the mains go OFF for some reason the LED's should automatically switch ON.

Would the above circuit be enough for my need or should there be a modification.

Regards,
Anish

1. You may build the THIRD circuit given in the following link:

Regards.

35. Dear Swagatam,
This Faisal Mateen Again, i need to know that should i use this 50 LED driving circuit by 220 v Ac Directly , the purpose of using this circuit is for a commercial use, i mean i am making a LED Decorative Column for outside a Shopping mall,i have to fit around 550 LED's In each column and have to illuminate small 5mm Warm White Led's, kindly suggest what kind of circuit should i use???
Each column is having around 500 to 550 LED's so i am thinking to make LED Series String for some more or less 50 LED's.
Regards/Faisal Mateen (Itech)

1. Dear Faisal,

Using as capacitive power supply is always risky, so you should go for a transformer type or an SMPS type of power supply.
I think the Chinese made LED strips which operate at 12 volts would be ideal for your purpose, you may use a 12v/1amp smps power supply to light them up all very easily.

36. i want to know that voltage rating given on capacitor 105k/400v is rms or average voltage rating.

1. It's RMS (average voltage value)

37. Dear Swagatam,

I have seen a number of LED Tube lights. but i am a bit confused as to which one shall i construct. In this regard i need your help in choosing an appropriate circuit which can render me the same illumination as that of a 36 or 40 watt tube light.

Regards

Nagaraj

1. Dear Nagaraj,

You may have to incorporate hundreds of LEDs to produce light equivalent to an FTL, the above circuit would be OK if you used around 500 LEDs.

Regards.

38. Dear Swagatam,
I am IT Operations Manager working in MNC. Very interested in LEDs.
What is the meaning of MOV in your first circuit. I am bit confused here :-)
I am more interested in LED technology. What is Maximum LED brightness we can get from a layman's perspective ?

Ajay

1. Dear Ajay,

MOV stands for metal oxide varister which has the property of grounding voltage surges for a fraction of a second, and therefore become useful for guarding electronic circuits from instantaneous surges.

LED brightness will depend on the number of LEDs you use, the more you use the more brightness you get, if you use reflectors, the brightness will get further enhanced.

39. Dear Swagatam,
To question asked by Ajay, is it mandatory to add MOV or Zener 200 volts 1W in both the circuits. Can we make circuit without this also :-). Where can we find these two parts (MOV or Zener 200V 1 W)
If yes what is the drawback ? Based on the above two circuits how many minimum LEDs we can glow ? I am just making first experiment of my life with these LEDs :-). is it safe with out MOV or zener .

Yejaz----asyejaz@gmail.com

1. Dear Yejaz,

These have been included for suppressing mains surges, and for ensuring longer life of the LEDs.

However it may be not absolutely necessary to include them, I have provided one link just under the second diagram, as a beginner you can try that circuit as it's very simple and reasonably reliable......

40. Dear Swagatam
Please recommend 12v Circuit for Led 100 no's. We have no power in our area so i want to use LED from 12V power. Please provide detail it should be in parallel or series 100 LEDS from 12V.

1. Dear Risetofly,
If you are using ordinary 5mm LEDs, then make series of three LEDs with a 150 Ohms resistor.
Make 33nos. of such series and connect all of them in parallel.
Now connect their common terminals to the battery with correct polarity.

2. Dear Swagatam
Thanks for your recommendation. I'll do so.

41. Mr.Swagatam, i liked this circuit and i'm going to do in my home but i would like to add 12-0-12V/3amps transformer and 12v/7amps battery with it but i don't know how to add these into above circuit so, can you please design a circuit as by my wish.

1. Hi Deepan,

I think you should try the following circuit, you can use ordinary 20mA/5mm leds in place of the shown 1 watt leds, also the led resistors should be made into 150 ohms instead of 10 Ohms.

42. Hello,
I checked Ur circuit and it's very OK. but I want make a higher power circuit ( about 24W and 36W - about 270 to 300 LEDs ). I found a circuit :

http://www.brighthubengineering.com/diy-electronics-devices/119887-replacing-fluorescent-tube-fixtures-with-led-light-fixtures/

But the problem here is : it's not diode bridge => it flash because frequence is 50 to 60Hz.

So can U fix it ? Waiting for Ur reply !

1. Hi,

To reduce flickering effect you may add a 100uF/100V across the positive and negative of the circuit...

2. You are right it should be 100uF/220V, if it's available with you, you can use it.

43. yeah ! Thank U very much ! I hope you will help me later !

Regards !

44. And can you design a timer relay circuit with : 999sec , counted up/down to on/off relay, controlled by three buttons: up and down and set / selected with Digital IC

1. I'll try to design and publish it....

45. And this is my light with 50 LEDs and it's Beta ! :]
http://nt3.upanh.com/b3.s35.d4/3489f5a7cf0073853784658f787d3694_51511683.20121206029.jpg

1. sorry it's not opening...

46. Sorry, I'm in Vietnam. Maybe upanh.com not support Ur country ^^
http://i1281.photobucket.com/albums/a502/merleyailme/3489f5a7cf0073853784658f787d3694_5151168320121206029-1.jpg

1. Hi Merley,

That looks great.....I'll publish it in the above article.

Thanks!!

47. swagatham,
what is the output current and voltage of 105/400v capacitor? can we use 474/ 400v ?

48. It's 70mA @220V, yes you can use 474/400v with less number of leds.

1. ok.. Thanx swagatam.. !

2. swagatham,
can we connect a led chaser circuit with this circuit... ! and please tell me how to connect a cd4060 circuit with this circuit... !

3. and vat bot the output voltage ? is it 220v for 105/400v capacitor ?

4. You mean you want to use a capacitive power supply for driving a chaser circuit? is it...??

5. yes without regulation it will be 220V....

6. exactly swagatham... led chaser with capacitive power supply... ! like led curtains... !

7. OK, here's a simple transformerless PS circuit:

Connect the above with this circuit:

49. mr swagatam i just want to know where can i connect the phase and the neutral?what is that...and what is tha other line?thanks..

1. Mr Hehnry, the phase and the neutral points are indicated in the diagram, that other line goes to the led resistor common point, it cannot be seen because of the white border of the image.

2. hi sir,
what is the method of selecting inrush current limiting resistor
in led lighting for 230v. (as it is shown in in 230v ac nuetral
coming from rectifier) is there any calculator software for
these led lighting on 230v ac mains please post

3. Hi Henry,

I cannot see any resistor at the neutral in the above diagrams,

anyway if you want to use a limiting resistor at the mains input, you will have select an arbitrarily optimized value, there's no specific formula for this.

50. hello swagatam ,

my self sanjeev kumar

i like all ur post can u help me get the emergency led light circuit without LDR

1. Hello Sanjeev,

You may try the last circuit provided in the following article:

51. Hi sir,
can we use pc atx power for lighting series led/led lights, if so any modification to pc psu is required? please tell me what modification is necessary

1. Yes it can be used, which supply do you want to use from it??....by the way an ATX PS is too bulky and unnecessarily big unit for powering LEDs, LEDs can be powered even from small AC/DC adapters.

52. sir what will be the power?
watt

1. Around 20 watts.

53. thx,very cool circuit sir.i make it,too much light

54. Hi sir,
I want to use 12v and 5v from atx power for testing of led series circuits

1. For 12V you can connect 3 white leds in series with a suitable limiting resistor, with 5 volts only one white LED can be accommodated with a suitable limiting resistor.

55. Hi, Sir,
how many led in series can be connected with 684 k and inrush current limiter
ohms and watts to be used in neutral, dc side resistor ohms/watt required
and bleeder resistor is 1M or any? please tell me.any special circuit is
684K capacitor, White Leds, 1M resistor 1/4 watt, rest you specify me about
other resistors

1. Hi, you may use the above circuit with 684/400V also, just make the LED series resistors to 56 Ohms 1/4 watts. rest everything will remain the same.

56. Hi, Sir,
48 leds in series with 474k/400v what is the led resistor and current inrush limiter resistor in
neutral to be used. i have 100 ohms 1 watt and 150 ohm 1 watt resistors and 1M 1/4 watt resistors

1. The value is not so crtical, try 100 ohms, it will work, connect all the LeDs in series.

57. Sir,

Can I use minimum 10 LED in this circuit, if not what changes I should do?

I read all comments, mostly of viewer asked that same type of question. can u issue a Table/ Chart that refer to use no. of LED can use?

1. Nothing is much critical in this circuit so there's no stiff calculations here, for 10 leds you may just reduce the rating of the input capacitor....use 474/400V instead of the shown value.

58. Hi Sir,
I have 12v ac/dc adaptor. but its output is showing 17v - 18v dc why?
can i connect 5 white leds with resistor?

1. Yes you may connect 5 LEDs in series with a series resistor.

59. comment postings not working :/

60. sir,
I m electronics hobbyists and don't have deep knowledge of electronics so asking you a question

474 = 474K = 0.47uf(MFD).

working on AC so I asked you.

1. yes that's correct!

61. Hi Sir,
what is the current carrying capacity of 8mm and 10mm leds and forword
voltages. can we connect in series (around 12 leds of 10 mm) with
474/684/225 etc capacitor and 100 ohm resistor 1 watt. for these circuits
how to calculate power consumption of full circuit.

1. Fwd voltage = 3.3V

current = 30mA

Yes it will work with these capacitors

Measure the current by an ammeter, and then multiply it with the voltage drop across the series, it will give you the power consumption.

62. Sir,
I want to use this circuit in used CFL, use 5 to 7 LED, what changes I should do.

Want to say u thank because I am layman in electronics and need guidance to make circuits, and u do this, the big thing is, reply in very short time. so thanking you again, plz continue this.

1. You are welcome Akhilesh!

63. when 474 is connected to AC it measures 140-150v ac. when it is looped to
bridge out put at bridge is 252v dc. please tell me which voltage has to considered while calculating led series resistor? weather 150v or 252 v

1. Actually calculations does not matter much for capacitive power suppies because the current involved is very low, anyway you may use 252 as the supply voltage, but results will not be accurate due to the above fact.

You may use any approximate value starting from 100 Ohms onward for optimizing the desired amount of light.

64. This comment has been removed by the author.

1. where's the "Pic" Bibin???

2. Sorry... my mistake.. the picture is attached to the second comment !

PIC

65. Serial Led Lights Made using 474 capacitor and rectifier....

PIC

Thanks swagatam for your support... !

1. Thanks Bibin, I'll put this up in the above article.

66. sir,
I made this circuit with capacitor 474K/250V, Zener Diod 1Watt/120V, and 100 Ohms(2 watt), used with 7 LED but its not working,
I checked circuit 3 time but dont know the reason.

the component voltage is problem?

1. Did you connect the bridge rectifier?

Remove the zener diode.

What result are you getting by the way?

component voltage is not the issue.

67. one thing forget to say u, I used 7 pcs. (8MM LED).

68. I made it......ha.......ha.........ha......... with above given component specification by me.

but again a problem, the LED light is not smooth, its flickering like old days "Tubelight". what is reason?

1. It shouldn't flicker, something's wrong with your components or connections.

69. Sir,
I got calculation chart for LED at (http://danyk.wz.cz/ledzar_en.html).

The same I want for ur circuit, can you prepare this. its helpful for all ur followers.

1. Hi Akhilesh

You can calculate it yourself, it's very easy just put the values in the slots and you'll get the results.

70. Hi, Sir,
can we use pc ups transformer for led lighting? how to check the same,
I broke out old ups and removed tansformer, there are 4 leads is yellow, blue, green, and black one side. other side 2 big leads red and blue
now question is to which leads we have to connect ac and check other side.

1. Yes you can use, but it will be unnecessarily bulky, even 500mA transformer can be used for lighting LEDs,
the output of the transformer which was connected to the UPS 220V socket will now become the input for the mains.

The secondary outputs may be confirmed by a DMM.

use a 1 amp fuse in series with the mains input for safety.

71. Hi Sir,
can you give me capacitor power supply circuit for 48 dc volts with 60 ma
current output. my mail address is hvac8910@gmail.com

1. Hi hvac,

you can use the capacitive power supply which is shown in the above article, just connect a 48V 1watt zener across the output of the bridge rectifier, it will provide you with the required power.

72. Hi, Sir
this is hvac. can you give me a circuit for 12 nos of 8mm leds in series.
capacitors required and resistors for leds and resistor in mains neutral

1. you may use any of the above discussed circuits, just make the input capacitor to 0.47uF/400V

73. Hi, Sir,
When using capacitor power circuit for led lighting, how to select resistor, and resistor power rating

1. you may the following formula:

R = (U - FWD)/I

where U is the voltage after bridge rectifier, FWD = the total forward of the connected LEDs and I = minimum required current of the LED.

74. Hi Sir,
This is hvac, can we do led light only with resistors (without capacitor, etc) Resistors before bridge is
in line and in nuetral. where i can find the calculator for this? and what is the power of resistors (watts)
and safety factor for voltage flactuations. (Resistors-bridge-leds in series)

1. Hi Hvac,

You may use the formula given in the previous comment.

Safety factor must considering "I" in the formula.

for finding watts of the resistor, just calculate I(LED) x V

75. Dear Sri ,

Please let me know what is the capacitor do I want use for the 38 LED, ? and can u pls tell us, how we can calculate the capacitor value for LED like below....
8 LED = capacitor value ?
20 LED = capacitor value ?
40 LED = capacitor value ?
60 ?
100 ?

Thank you,
sanjeewa

1. Dear Sanjeeva,

first you will have to find the current required for the LEDs. The capacitor should be able to provide this much of current. for example for 5mm the current will be 20mA.

To find capacitor current you will need to calculate it by finding its reactance, then using Ohms law.

http://www.sengpielaudio.com/calculator-RC.htm

2. the reactance value will directly provide you with the capacitors maximum current rating.

3. I'm sorry, the reactance will provide you with the resistance value of the capacitor....to get current, use Ohms law:

I = V/R = 220/reactance

76. Dear Swagatam,

Thank you very much for your quick response and help,
I am very new to this LED Circuits, but I made this and it's working very nicely and iam very interested in LEDs Circuits. so pls let me know belows

1)if I change this circuit to 30 Led or 40 Led, what are the changes I want to do ?

2)how to use the LED lamp online calculator ? (http://danyk.wz.cz/ledzar_en.html) Bcoz to your above 15 LED circuit

Mains voltage : 230 V~
Mains frequency : 50 Hz
LED voltage drop : ??? V
Desired LED current : ??? mA
Number of series LEDs: 15
Capacity of C1 : ?? uF
Capacity of C2 : ?? uF

Voltage on C2 (has to be rated to more than this): V
Resistors R1 and R2 (both the same) : ohm