This is a modified version of the circuit Super bright LED Night Light published here. This circuit is submitted by Mr. Seetharaman and its full credit goes to him.
This is the circuit of a well tried and reliable 230 Volt AC mains operated 24 LEDs (super bright 50mA LEDs). While practically compare the brightness between this circuit and 11watts tube, the LED light is much better. The layout is made in such a way, you get uniform illumination. A photograph of the cicuit is also given in this post.
588 Comments
i have done this with 1W resistance is it any problem to do.
and how many power LED can be added to this in how many watts
dear sir,
i have connected 70 no.of 5mm led in series with using 1 uf poly capacitor . i shows me 10.46 ma current. how this value come, please give me answer. as i tried more but fail to get this fig……my all calculation fails. on dc side it shows voltage of 260volt ? how
dear sir,
i have connected 70 no.of 5mm led in series with using 1 uf poly capacitor . i shows me 10.46 ma current. how this value come, please give me answer. as i tried more but fail to get this fig……hope u answer
PLEASE HELP ANYONE…
Which Electrode capacitor can be used replace of 1uF 400 Volt(Poly) as I did not get it local shop…
Also can you share any calculation for the same…As Polymer capacitor is not available in my aria…
no other capacitor can be used it has to be non polar with 400volt DC operation or 500 volt AC operation.
Sar l try to make a 8mm white led serial 50p&100pc but not suaxfully work please sand me 230volt ac driver ckt com ponunt diagram
Sir i dont have any knowledge on electronics i am a AC electrician but vry intrested in led circuits pls guide me sir how to make led serial lights,how to use resistors,and capacitors how to calculate them and send me some simple circuit diagrams thank u sir
Dear Seetharaman sir,
You were doing a commendable service to so many enthusiasts for such a long time. If all the comments of 1st page itself are copied and pasted in Microsoft Word, 65 full A4 pages are filled up completely.
Salutes to you. I am also an electronics enthusiast but don’t have any knowledge.
Sorry to see no replies for quite a long time,
HAVE YOU GOT MARRIED???
regards
Hello boss..
AS PER YOUR CIRCUIT DIAGRAM…
Which Electrode capacitor can be used replace of 1uF 400 Volt(Poly) as I did not get it local shop…
Also can you share any calculation for the same…As Polymer capacitor is not available in my aria…
Dear Sir,
As I learned from your comments, the current output of 1uf capacitor would be 100ma. Also total volatge consumed by leds would be 72-80v. If this is true, then 100 ohm resistor after the bridge should be 800 ohms (80v/100ma) or (80v/50ma drawn by leds)= 1.6k ohms. Am I thinking correctly.
Sir I wish to create serial lights for Diwali. Using the calculation shown I’ve calculated the required. Please check if the below specifications would be okay with yours above circuit for 220volts supply.
1) 5mm 20mA 3.2v x 40 white leds
Resistor 470 k
Other resistors of 100 ohms
1st Capacitor 0.47 mF 400volts
2nd Capacitor 10 Mf 400 volts
&
2) 5mm 20mA 3.2v x 95 white leds
Resistor 470 k
Other resistors of 100 ohms
1st Capacitor 5mF 400volts
2nd Capacitor 10 Mf 400 volts
Sir please guide me in doing so. Waiting for yours reply.
Thanks
respected sir,
suppose i want to connect 4 led in series, them what could be the value of capacitors .
dear sir,
do you have any 12 volt operated LED circuit diagram?
Dear sir,
I am try to make led lamp by this circuit but it not work and I am using 3v 20mA LEDs….please help me sir…what can I do??? I want to make this type of led lamp…
HELLO SIR,
I WANT TO GLOW MY COLLAGE NAME BY LED.
PLEASE SIR I REQUEST YOU. YOU ARE SEND
ME CIRCUIT OF LED GLOW IN PARRLEL.
Sir, I want to know how total power consumption is calculated in your circuit. I have already designed this circuit but not able to calculate total power dissipation.
how to choose 100 ohms in series??explain me sir
How do you define 1uf capacitor for 24 LEDs? if I use lee Leds then what will happen? if I use 30mA & 3.3V rated 5mm LEDs then?
i have super bright led 16, and normal blue 4, red 4, led s. is it good? or send me resistor name for normal led + or – side.
hi chandana can you help me to built a genious loyalty circit main opprated
230v circit for this leds 30 or 24
hi sir,
i am regular reader and follower of you circuit…but i have a doubt the is it necessary for to calculate all the possible value in a circuit….because i have built two circuit without any calculation and i have achieved the output….
sir please guide me as your student…and my mail id is guhanvijay92@gmail.com……………
by one of your student….thank you sir
Dear sir,
I am a bit confused about the normal AC value say 230V and it’s RMS value of about 325V in the calculation of the poly cap value in the circuit.Is it not advisable to calculate the capacitor value using the RMS value instead of 230V?
Also why not use a 400V rated smoothing cap all the time instead of 160V towards the safety of the LEDs?
A Quick reply is very much appreciated.
Thanks in advance
Neville
Since 160 volt is sufficient and quite compact in size as the space is limited it was preferred. if space available is plenty you can use 400 volt s capacitor for filtering. For 1uF it should be 400 volt DC working voltage or 250 volt ac working voltage. as the voltage across can reach the peak voltage of the applied ac rms value, hence 400 V DC is chosen.
Sir,
I’ve made several ckt using ur ideal ckt.
At today’s morning, I’ve made a ckt which output is 9V,200mA. When I connect it with 220V AC, it was getting burn. Quickly I disconnect the ckt. Sir I think the problem is with the filter capacitor or other I don’t know.
Now sir pls tell me about the modification ASAP.
Sir, please replay…
This circuit is suitable for 50ma application with the led circuits connected as shown. not suitable for higher currents, use suitable smps as per your requirement.
Dear Sir,
I want to make 10 nos.(1 WATT,350 mA) LED bulb. What modifications I have to do in above circuit? How to calculate electrolytic capacitor value and resistor values for this design?
Can i used electrolytic instead of the polyester?
Dear Seetharaman Sir
Please reply.
use SMPS for your requirement. these circuits are meant for a maximum of 100mA only.
Dear Sir,
What modifications to be made if i’m using Min:3.0V Max: 3.6V, 350mA power LED?
Use SMPS with 350mA constant current and use 3 leds in series.
Dear Sir,
Please help me on A dim glow from lamp after switch off.
Please help me on that..
Thanks in advance.
Dear Seetharaman Sir,
Please reply.
This is due leakage current in your fittings. this will not affect the operation of the circuit.
Dear Sir,
I checked the circuit again but i can’t find the leakage of current. I am using 1OOuf 400v cap.
Please help me on that.
Thanks in advance.
Remove power supply to the LED light if no glow. you are having the control switch in neutral instead of in live. Please do the necessary correction.
Good afternoon.
Its me again, i am sorry to bother you again, you already gave me the specs for 127vac, but my leds are not 50ma but 20ma, do i have to change the values you alredy gave me.
Thankyou in advance, kind regards.
Paula
hi i want to glow more than 500 white led… is 1.2uf is enough..
wat r the changes in components.
Hi you have to use 5 strings of 100 leds
Good afternoon.
It is a great circuit, congratulations. I am trying to build the same circuit but iam inexperienced in calculations, what would be the values if i am using 25 standard 20ma 3.5v blue leds at 127vac 60hz?
Thank you in advance. Kind regards
Hi Paula for 127volts 60Hz operation, you can use the above circuit with 1uF reduced to 0.82uF 250 volts and 10uF can be 250 volts DC. other components can be same.
for 20ma the components will change, you have to reduce the capacitor to 0.9uF (use 0.56uF and 0.33uF in parallel) other modifications as suggested earlier are ok.
Hi, I’ve 1w 300ma LED. want to prepare the above circuit, what is the necessary change should I made. I’m a amature and have only basic knowledge of electronics. Already prepared some of your amplifier circuits and willing to assemble 100w subwoofer soon.
sorry the LEDs are 1w 350ma, not 300ma.
Thanks.
For 24 nos 350mA LEDs 1uF should be increased 6.2uF and 100 ohms should be reduced to 33 ohms 5Watts 10uF should be increased to 100uF 400 volt. all other components can be same. Still I recommend you to go for 3.3 volt SMPS of required current and connect all LEDs in parallel, which will be more reliable.
Hy i have made a 2 circuit with 38 and 39 leds and i use a 0,47uf/400v and 10uf/250 for last capacitor and the resistor at 100ohm/1w
From mai calculation at 3,3v/25mA ..for 240v AC, 38×3,3=125,4v; 240-125,4=114,6v need to drop. Resistance 114,6/0,02=5730ohm so C=1/xc*Ѡ or C=1/2pi*f*xc so C=1/6,28*50*5730 and 10−6 /1799220 = 0,5557uf.
So what is the best choice for C 0,55uf or 0,47uf
and for 10 leds at 3,3v/25ma C=0,307uf at 240v or 0,404uf at 230v
In a old post you respond …at 67 leds/20mA/3,2v need 0,82uf but, from my calculation c=1/6,28*50*780 C=1/244920 so c=0.0000040829658664Farad=(4,08uf)
or 24led/25mA need 0,39uf and ofter my calculation need 0.519uf
So where is my mistake? how to calculate value of C for 67leds or how to calculate with a large number of leds because the voltaje drop by led it’s so big and mains supply is only 230v. can you detail calculation because i don’t understand if i use 85, 90, 100, 120 leds.?
i don’t understand
regards
Hi the basic is, a rectified output for a given RMS AC in is, voltage RMS in X root 2 (1.414) now you go ahead with all your calculations. That is 325 volt DC for 230V RMS in.
Dear Seetharaman Sir,
I’ve made this ckt. It’s awesome. All the component are working so nice. Even any of components were heating up.
From the comment I come to know that with supply and without load the ckt might be burnt. Now my question is:
If any of LED got fused & got disconnect any of LED then the whole ckt will be open. Then what will happen to the ckt? will it be brunt or its any component?
to avoid this problem you kindly replace 10uF 160 volt with 400 volt. now it will take care of open circuit voltage of 325volt approx with 230 volt AC input.
WASEEM, your calculation(October 21, 2013 at 8:38 am) is right but the formula gives capacitance in F(Farad). To give microfarad multiply it with 1000000, that means 1F=1000000uF
Dear sir,
I’ve calculate the value of polyester capacitor. I’ve got 730,068 pF(considering a circuit with 4 LED, each 3 V, & 50 mA).
For this value, the nearest standart value is 684K or 704K. Now sir please suggest me that,
1. Is my calculation is correct? If wrong what it should be?
2. Do I need to change other component of the circuit? If yes then, What will the change of discharging resistor, current limiting resistors & filter capacitor value be?
Sir, I’m waiting for your valuable replay & help me out not to burn or blast my components by giving correct value.
Thank your so much.
Your obedient,
Saiful
Hi Mr. Seetharaman,
what parts I need to change if i want to build this circuit using 12 nos white leds (100ma)? Thanks.
Dear Seetharaman Sir,
Thanks for ur hard work, I mean rply to all with care. It’s very good of u I think. Sir, now I’ve to made a ckt with 4 led. Each r 3V, 50mA. So pls sir help me out. Tell me about the modification. Thank Sir.
From,
Saiful
Hy i have made a 2 circuit with 38 and 39 leds and i use a 0,47uf/400v and 10uf/250 for last capacitor and the resistor at 100ohm/1w
From mai calculation at 3,3v/25mA ..for 240v AC, 38×3,3=125,4v; 240-125,4=114,6v need to drop. Resistance 114,6/0,02=5730ohm so C=1/xc*Ѡ or C=1/2pi*f*xc so C=1/6,28*50*5730 and 10−6 /1799220 = 0,5557uf.
So what is the best choice for C 0,55uf or 0,47uf
and for 10 leds at 3,3v/25ma C=0,307uf at 240v or 0,404uf at 230v
In a old post you respond …at 67 leds/20mA/3,2v need 0,82uf but, from my calculation c=1/6,28*50*780 C=1/244920 so c=0.0000040829658664Farad=(4,08uf)
or 24led/25mA need 0,39uf and ofter my calculation need 0.519uf
So where is my mistake? how to calculate value of C for 67leds?
i don’t understand
regards
Sir,
I am a medical doctor and a newcomer to the electronics field as a hobby.
Your forum I must say is very educative and practical. I built the above circuit and is working very well over the past few weeks. I wish to build one with 69 straw hat type bright LED s. Could you kindly let me know the component specs please. I thank you very much in advance and for this very enjoyable forum.
Thank You
Hi The straw hat LEDs require 3.2 volt at 50mA component requires changes are 1uF to 2uF and 10uf 160 volt to 22uF 400 volt
Dear Mr. Seetharaman,
What changes are reqd. for 69 25Ma LEDs in series and to get a good light output? Thanks a lot in advance
You can use the same circuit as above increase capacitor 10uF voltage to 400 volts
Sir.
Can you suggest a reliable driver circuit-capasitive/resistor circuit
to drive 1 Watt high power leds in TEN numbers.
It is highly appreciated if you could post me as soon as possible.
Thank you,
1watt LED requires 3.2 volt at 330mA for 10LEDs in parallel a power pack of 3.2 volt 3.3 amps SMPS power pack. In the above circuit 1uF to be increased to 2nos 2.2 uF in parallel. and 10uF 160 volt to 100uF 400 volt. both 100 ohms to 33 ohms 5 watt. But I do not recommend a capacitor power pack instead my strong recommendation will be for a switched mode power supply.
Sir,
Please let me know how to design the resistors in this circuit(400K & 100 ohms)?
Hi Anupam 2 100 ohms are for limiting the surge current through the circuit. it is limited to 1 amp approx with 200 ohms. The 470K is for discharging the 1uF capacitor. A dim glow from lamp after switch off can be reduced. This value cannot be reduced very much as it is likely to pass excess current through the LEDs.
In the event of plugging out the lamp and touching the lamp plug may give a nasty shock due to the capacitor charged energy.
what is the life spam of this led circuit
How to calculate the value of surge current limiting resistors(as in the above circuit it is two 100ohms)?
sir please reply..
The surge current should be limited to 1amp approx hence 200 ohms is chosen
Thank you sir.
Sir how to calculate the value of 10uf,160v capacitor?
The capacitor should be at least 10 times the supply capacitor such that it takes care of the inrush current from 1uF to protect LEDs from large surge current, hence 10uF is selected. For minimum ripple across the LEDs for professional applications it should be at least 100uF for least ripple. But for our applications 10uF 400 volt will do. if 100uF 400 is available and space is available you can use 100uF 400 volt for absolute flicker free illumination.
Sir in the picture it is 10uf 160v.So it will be 160v or 400v?
160 volt will do if the load is not getting disconnected. If the load gets disconnected due to dry joint in the circuit then the capacitor will get a peak voltage of 350 volt, a 160 volt capacitor may get damaged, hence 400volt is preferred voltage value.
Thanks sir.
dear sir,
i have 86 led’s circuit with 4.7uF CAPACITER AND 822J POLY CAPACIER, 4 NOS 1N4007 RECTIFIRE, 6.8k ohms resister,560k
ohms resister, 820k omh resister. i connect all thigs but the brightnes of led is low. pls what is the problem? and pleas send me 57 led’s and 100 led’s circuit diagram (manasmum(at)gmail.com.
thank you
You have not mention LED current and Voltage. I take it 50mA and 3V.
86 LED Drop 86×3=258V. But yours mains supply is 230V. How can it glow brightly?
And your capacitor 822J =8200pF=0.0000000082F ,
it reactance=1/2π×50×0.0000000082=388182.79Ω
and it drop the voltage=388182.79×0.05=19409V.
Calculation
I=Led Current(in A, basically LED Current in mA ), V= Led voltage
Voltage drop by Leds = No Of Led × I
Remaining Voltage =230- Voltage drop by Leds
C1 drop the Remaining Voltage
Xc= Remaining Voltage/I
C1= 1/2πFXc (will get in Farad, convert it to uF by multiplying 1000000)
thank you sir
you make a mistake in calculation…Voltage drop by Leds = No Of Led × V not for I so how to calculate for 86 leds?? because 86×3=258 and remaining voltage is negative if 230-258=(-28)??? sau what is the remaining voltage drop by C1? (-28V)? how to calculate with a large number of leds because the voltaje drop by led it’s so big and mains supply is only 230v. can you detail calculation because i don’t understand if i use 85, 90, 100, 120 leds.
How can use the clasic formula R=V/I or Xc =V/I where V= V of supply -V drop by led and I current of led?
Since it is RMS voltage is the input to your bridge rectifier. The basic is RMS X root 2(1.414) is the DC output. This basic you have left that is the problem in your calculation.
Dear sir
i want to build a similar circuit using 40 LED with 150 mA current
what are the changes that have to be made for this circuit
with reagrds
or should i use it as it is
Dear Sir,
Can you please indicate me the max numbers of straw hat LEDs (3V and 20MA)that could be used for 1uf and 0.47uf polyester caps respectively in this circuit.
sir,
how to construct a 45 no’s hi bright white led and 5 no’s red led (only red led blinking) in AC mains. I wants to construct in series circuit.
Please help me understand the full circuitry
Mainly th input cap 1uf 400V and the calcuations which WASEEM AHMAD did R= v÷i. 153÷0.05= 3064 ohm if the calculation is correct where is the R value located in the circuit
Hi Siddharth. we are using the Xc of the capacitor to drop the voltage. if you use resistance it will dissipate V X I power. here the capacitor voltage lags by 90deg the current through it, hence the dissipation is zero. Hence the real wattage consumed is the power consumed by LEDs only.
Hi
using the Xc of the capacitor to drop the voltage. if you use resistance it will dissipate V X I power. here the capacitor voltage lags by 90deg the current through it, hence the dissipation is zero. Hence the real wattage consumed is the power consumed by LEDs only.
Sir can u plz tell me the requirment of resistance accross capacitor, and how it’s rating decided.
It is just to discharge the capacitor when you switch off the lamp. if you do not connect, in the event of removing from the holder and accidentally touching the terminals of the light you will get a nasty shock. Should be capable discharging the capacitor in just few seconds.
Hi
well I ve studied from arts stream learning about elec. components is my hobby. and I make grammatical misteks in english so plz ignore them.
well gonna tell u 2 calculate the main component of this circuit polyester cap. with e.g.
in the above circuit
we gonna glow 24 leds those are 3.2v 0.05 amp in 230v ac.
so 24×3.2= 76.8v we require to glow r leds n 230- 76.8= 153.2
so we need to drop 153.2v. now we ll calculate the resistance by
R= v÷i. 153÷0.05= 3064 ohm
now cap. right formula is
C= 1/2pi × f × xc
C for capacitance in farad
F for frequency of suply in hertz
XC for capacitive reactance in ohm
one PI is equal to 3.14….. 2pi is 6.28…
so 1/2pi= 6.28 × f= 50 × XC = 3064 OHM
1/6.28×50×3064= something like 962096 now
1/962096 = 0.00000103…… uF still confuse ok multiply 0.00000103….to 1000000= 1.0….this is one microfarad
hit thanks
Hi Waseem your calculations are correct but in final calculation it is 1 / (2pi X f X Xc) all should come in denominator. where F is in Hz, Xc is in ohms and capacitor value in Farades ( 1000000 uF) so will get 1.039uF the nearest standard value is 1uF.
Thank’s dear
Hello Sir,
Which LED I use for best result.
Hello,
I want to make 10 nos.(1 WATT,350 mA) LED bulb. What modifications I have to do in above circuit? How to calculate electrolytic capacitor value and resistor values for this design?
Thanks,
Kaushal.
Hello,
I want to make 10 nos.(1 WATT,350 mA) LED bulb. What modifications I have to do in above circuit? How to calculate electrolytic capacitor value and resistor values for this design?
Thanks,
Mohan.
sir can i used electrolytic instead of the polyester?
dear sir this is satish.
sir i am a fresher .i want to design the led desigening please give me the suggestion .for 10 no`S LED designing.AND circuite
sir,
tell me detail calculation about RC parallel block. how it work in this circuit. how to calculate Watt. i need calculation about section that is before bridge.
sir,
tell me detail calculation about RC parallel block. how it work in this circuit.
Hello Mr. Seetharaman
I want to make 3 to 5 nos. LED on main operated at home.
how can i do it.
please suggest.
Thnx.
Pravin C
Yes you can assemble the above circuit on standard dot matrix PCBs and use.
Hello Mr. Seetharaman
I want to make 3 to 5 nos. LED on main operated at home.
how can i do it.
please suggest.
Thnx.
Pravin C
Thanks………… a lot.
Sir,
I have made a Mains Operated LED Circuit using 46 leds and they are working fine but can u please help me with the modification required to make 2 circuits one using 77 and second with 110-120 white leds of 3.2v,25mA i am a new follower of your site i wish u will help me thanks.
hi danda for 77 leds of 3.2 volts 25 ma use 1.2uf instead of 1uf 400volts no other changes are required.
you can use 100 leds in the above circuit just link 1uf 400 volt no capacitor required, other components are required no change.
Sir,
Am a new follower with little knowledge in DIY projects. Your reply to Soumitra Danda for 100 LEDs you have advised him to use a 1uf 400V cap is to be used and no capacitor is required for 100 LEDs. I guess its a typo as 100 LEDs are being used so there’s no voltage drop is required right? Also each LED will consume 3.2V each so how will all 100 LEDs glow in optimum brightness as the supply voltage is only 220V max? Or are you suggesting this for the better life span of the LEDs? Can you elaborate on this? Am also planning to build this soon for decorative purpose. How about 68-70 LEDs in a circuit for the optimum brightness? Pls be in detail.
Hi If you rectify 230volt ac and across the filter capacitor the DC available will be AC RMS X root2 That is 1.414 X 230 That is 325 Volt DC. Hence for 100 LEDS of 3.2 volt you do not require any dropping capacitor. For 77 LEDs you have to drop 325 – 246.4 volt hence 1.2 uF.
for 77 leds voltage needed is (77×3.2)=246.4volt Then why to add 1.2uf capacitor..didn’t understand this.sir please explain.
Sir,
I have made a Mains Operated LED Circuit with 46 white Piranha leds of 3.2v,25mA,angle 110 degrees and now i wish to make a few other circuits using 77 leds and 110-120 leds max, sir please help me with the changes required to be made to make this 2 different kind of circuits, i am very interested in building the above mentioned circuits please help me.
Dear Mr. Seetharaman,
I have built the LED circuit exactly as demonstrated by you for 24 LEDs in circuitstoday.com. I have used bridge rectifier instead of 1N4007. During testing, invariably, 2-4 LEDs go blank and have to be replaced. When I checked the current, it was 46.8 mA. I have used 5 mm white LEDs with 7 mm height (focussing type).
I have calculated the resistance to reduce current to 20 mA and it comes to 4000 Ohms. This is not a standard resistor. Please guide me. The lights have dimmed considerably after 12 days of use.
mr singh the circuit is meant for 60ma high bright 4 pin white leds. for two pin focus type tor sizes from 3mm to 10mm led is just 25ma only. hence use the same circuit just replace 1uf 400 volt with 0.33uf 400 volt. that is all the modification required. ensure the leds have enough ventilation.
Sir,
If somebody use 150ma(8mm .5w)led instead of 50ma led. You have told that he has to decrease the value of 100ohms .5 watts to 33ohms 1 watt of both the resistors and to increase the value of that capacitor 1uf to 2.5 uf and the capacitor 10uf 160v to 47uf 350v. What will be the power consumption? Is it (3.2 X .15 X 24) = 11.52 watt? And is it better than 30 watt cfl? And if some body uses 8 pieces of 150ma(8mm .5w)led instead of 24 50ma leds is there any change will be required? And what will be the power consumption? is it (3.2 X .015 X 8)= 3.84 watt and is it better than 11 watt cfl? Please reply. Thanks in advance.
hi sarkar you are correct about consumption and compared correctly with cfl bulbs, you have to add dissipation of the resistances also
Sir, Thank you so much for this valuable circuit. Please let me know that can we use half-wave power supply instead of full-wave (Bridge rectifier). Will it saves the power consumption of this circuit? Is it dis-crease the brightness of the lamp. Waiting for your kind response ? thank you so much
hi nalin you will get half power but to reduce flickering you may have to increase 10uf to 22uf.
can any body share idea about how to make a LED bulb. for 230 volt supply .
Dear Mr. Seetharam,
I have successfully completed the above circuit using 0.68uf 400v. The voltage across the LEDs is 82volts and consuming 30ma.
Since 1uf was giving 87 volts and LEDs were consuming 40ma but my LEDs need 30ma.
On the mains when I checked it was consiming 37ma which means 8.5watt
I again checked the LEDs, they consume 30ma 82volts which means 2.5watt
No components are heating up, everything working fine. I have used good quality 1N4007 to make the bridge, then what is consuming the missing 6watts.
Please advice
Rizwan
Hi Rizwan you are calculating apparent power that is total voltage multiplied by current. The active power is only LEDs consumption. As the voltage lags by 90 deg to current in a capacitor the power consumed by the capacitor is zero. If you use an accurate low power meter which ca measure up to 0.1 watts you can really see the consumption is just 2.5 watts. If say capacitor is consuming the balance power of 6 watts, it should get heated up!?. Whenever you calculate AC power you have to include in the multiplication voltage, current and power factor. Hope it is clear.
Dear Mr. Seetharam,
Thanks for your reply on the basis of which I studied the power factor (apparent and real power)
You are absolutely right, I am measuring the miliamps and multiplying by voltage which is real power for DC but for AC it is apparent due to power factor.
I don’t have a power meter but now I am convinced that the circuit is consuming 2.5watts and also your view that anything consuming 6 watt would heat up.
I have learned a lot from you and for me knowledge is precious than anything. I am so very grateful to you.
I have problem with my inverter which I think you can solve. If you give me your email I can send the details of the circuit and my findings so far, along with the pics.
Once again Thanks a lot!
seethasub@hotmail.com
hi sir i am a new follower of your circuit it is a beutiful reliable light waight main oprated circuit but it is only for 50ma 4pin leds but sir i make a normal 2pin 8mm 0.5 watt same nos leds which is available in market.
sir i built same circuit just replace 405j polyester capacitor instade of 1uf is this value is correct?in this four circuit two are burnt and two are ok those circuit which are burnt only the 10uf/250v capacitor are burnt what was the problem kindly known to me and if any change required please speak me my email- karakmriganka010@gmail.com i shall wait your valuable information and suggestion i hope ypu obliously help me as soon as possible.
thanks & regurds
MRIGANKA KARAK
hi sir, can i replace the led to 3x1w led?
any modification on the circuit?
the 4 diode what is the rating for the component?
can i use 1n 4007?
Sir,
you have used 24 leds each of 3.2Volts in series that would require 3.2×24 = 76.8 Volts- after the bridge.
How do u get 76.8 volts or something close to that value after the bridge?
what is the voltage at both sides of the bridge and how?
please reply
Sir,
you have used 24 leds each of 3.2Volts in series that would require 3.2×24 = 76.8 Volts- after the bridge.
How do u get 76.8 volts or something close to that value after the bridge?
what is the voltage at both sides of the bridge and how?
sir 160v 10 microF capacitor heat up soon as switch on the circuit
its normal or any problem in capacitor ? please help.
Sir what is the meaning of poly in 1uF 400V Poly:
it indicates type of capacitor to be used i.e. polyester type, will be compact and durable.
Sir,
If I don’t get 50 mA LED’s, can I arrange 20mA 3 LED’s (in parallel) in place of 50 mA single LED without making any other change.
Thanks.
Regards!
hi nice idea. the 50 mA LED is called 5050SMD as well it is available in 4 pin package. please go through following link http://media.digikey.com/photos/Vishay%20Photos/VLWW9600.JPG
Sir in the circuit LEDs shows only 2 pin. How will i connect 4 pins LED
they are two pairs of pins they are internally connected hence two connections only ultimately. for 5050 LEDs 3 leads will be on either side you have connect all the on one side as parallel, hence again only two connections
Plz define rating of diods.
Sir,
Thanks for reply!
May i get a circuit for higher no. of LEDs so that i can light my 12 X 12 room in my house.
E-mail: andleep2@gmail.com
Sir please explain me how to calculate capacitor for led circuits
Hi see my earlier replies on that on the following date
July 6, 2012 at 8:31 am etc
Sir I am beginner in electronics please explain me why we use capacitor in this circuit we can use only resistor by calculating resistor ohms law R=V/I and how to calculate capacitor
You can use resistance but the current and the voltage will be in phase hence the consumption will be V X I= 230 X 0.05(for 50mA LED) that is 11.5 watts. but if you use the capacitive reactance for dropping (in a capacitor voltage lags current by 90deg ie VI Cos pi VI X 0 that is zero watts) the dissipation is zero. so the power consumed is led voltage and the current flow through it. say each led is 3.2 volt at 50mA then the power consumed is 3.2 X 0.05 X 24 just 3.84watts a clear saving of 7.6watts.
Sir I am beginner in
Thank you sir, please explain me how to calculate capacitance and voltage of capacito.
Thank you sir for your reply
Sir for 20mAh led what change is required
Hi cool reduce 1uF 400 volt to 0.27uF 400volts (if not available use 0.22uF 400volt can be used resulting in small reduction in LED brightness not noticeable to our eyes)no other modifications are required.
sir wat s the voltage before bridge resistor
Hi VBignesh Around 80 volts DC at the bridge rectifier output.
Dear Mr.Seetharaman,
When this circuit is on will it protect from lighting,surge,or high voltage application.
Thanks
Wimal
Hi You have to use VDRs (265 volts) after 100 ohms and before 1uF capacitor or atleast Zeners (2nos 39volts zeners connected in series)across the LEDs to protect them.
sir
i have a problem for led circuit power calculation. i will make 30 nos of 230v led circuit. i make 3 circuit of this for one light. it take 87mA current.each circuit got 27 mA. i culculate this circuit power. P = VxI
P =230 x 0.087 P= 20.01W BUT CIRCUIT HAVE WRITE EACH CIRCUIT GET 1.6 TO 2.4 WATTS I WILL ATTACH THAT CIRCUIT
PLEASE SIR EXPLAIN ABOUT LED CIRCUIT POWER CULCULATIONSuper
Bright LED Lamp
This simple 1 watt LED lamp can give light equal to 11 watt CFL. It is directly powered from AC using capacitor power supply. The light from this 30 LED lamp can very well illuminate the room and is suitable for reading purpose also.
Capacitor powewr supply uses 474 J AC capacitor and standard full wave rectifier comprising diodes D1 through D4.C2 act as the filter capacitor. R1 is the bleeder resistor to discharge capacitor C1 at power off. 30 High bright White LEDs are connected in series with current limiting resistor R2.
CIRCUIT DIAGRAM:
High bright Flood light LEDs:
New versions of low current high bright LEDs are now used to make home lighting. These LED lamps can replace CFLs and Tube lights and consume only 1.5-2.4 watts compared to the 36-40 Watts of CFL or Tube light. These LED lamps can give 50,000 hours light without fail. Luminance range from 10,000 – 18000 MCD and the operating temperature is from -40 to + 95 degree. Current consumption range from 40 mA to 100 mA in various makes. Input voltage may be 2.8 to 3.5 volts.
Hi Mubarak the voltage of a capacitor lags by 90deg the current through it, hence the active power dissipated by the capacitor is zero. only the LED wattage and the power generated by the resistances alone need be taken for calculation. If you use a step down transformer for the circuit you have to take care of all the losses in the transformer like copper loss core loss coupling loss etc. Hence the above is the best circuit as for as the power consumption is concerned.
Dear Sir,
Wat is the voltage and mA rating for the LED’s and wattage rating of 110k (R1) used in the circuit published by you.
In this article part nane is given
Sir,
Now I have straw hat LED 2.8V, 20ma, whats the changes for this…….
Dear Seetharaman Sir,
I got Polyster capacitor 105K 630V, can I use this in place of 1uf 400V.
Hello Mr. Seetharaman,
if I used 144 pcs.LED white , what will be the value of discharge resistor(R1)atC1 ,the R2 the inrush current preventer, R3 after the bridge diode. Diode rating, filter capacitor C2 or can i used zener here? kindly
give advised , it will be wattage to 9 watts..
many thanks,
Rolando D.
Dear Mr.Seetharaman,
I have tried your circuit with 31 led and it was successfully working.Thank you for the post of valuable circuit.If i want to increase led up to 50 and what changes do i have to do?(because 24 led out put not enough for me to use @ home)If i use 50 leds what will be the out put watts of the circuit.
Tks.
Today My 10uf capacitor burn. Please reply sir.
Sir,
I got Polyster capacitor 105K 250V, can I use this in place of 1uf 400V. Actually I completed my circuit with this capacitor and it works perfectly but after 2 day 3 LEDs of my circuit is dead. My LEDs are very cheap and low quality because out of 100 LED my 46 LED are already dead when I tested that at my home. So I am in confusion that 3 LED in circuit are dead due to capacitor or because of low quality.
Regards
Hi Romy it is due to your LEDs mainly as they are not rated for 50mA. if it is 25mA you have to reduce the capacitor value to 0.47uF 400 volt capacitor. 250 volt cannot be used. with 115volt 60Hz it is ok but not with 230volt 50Hz.
Hi sir,
My question is that how can we find LED’s Rated mA. as I have the same problem as I am using .47uf 250Volt Capacitor for 10 LED with two Resistor 1M 1/4Watt & 470K 1/2 Watt.
Regards.
Dear Seetharaman Sir,
I connected a single 8mm,20mA White LED in series with a 0.22uF capacitor after the rectifier diodes without any resistors as I thought the capacitor is giving 20mA current but within few seconds the LED got burnt out. Kindly tell where I am wrong.Tell me the if anything else is required
Dear Seetharaman Sir,
I want to make circuit of 12 White LEDs using Capacitor. Please tell the
value of Resistors. Can I use a 0.22uF capacitor?
Also Tell me the formula to calculate the resistor values
Thanks!
Sir,
I did’nt find 1uf 400V polyester capacitor but I have same value i.e. 1uf 400v Electrolytic capacitor Can I use this in place of C1 in above circuit
Regards.
Romy
In this circuit you cannot use electrolyte capacitor instead of Polly due to AC Current.
Dear Sir,
i already make this circuit, it is very bright.
Now i want to add 80 leds, please help me
Regards
Mihindu
Hi Mr Seetharaman i would to like to know power consumption for 40 LEDs 3.2volt 20mA. how many watt it consume. tkz.
Hi Mohammed around 2.5 watts.
Hi Mihindu you want to add 80 more to this 24 LED circuit?
Hi Anir 2 X 100 ohms is for limiting inrush current to around 1Amp. For voltage drop and the LED current is known. Calculate the dropping resistance value required. Now instead resistance use the reactance of the capacitor. calculate the capacitor by using the formula
Frequency(f) = 1 / 2π (√R X C) where frequency in Hz, resistance in ohms and capacitance in farades.
how to calculate the value of capacitor (1uF,400v) and the value of resistor (100-ohms) used in the circuit
hi. . Whts the basic calculation of RC circuit (Resistance & capacitor)
(to be glow the no f leds)
Hi Kasun infact it should be 0.42uF to give 20mA but the standard value available is 0.39uF, which will be quite safe for the LEDs. With 1uF 2nos in series (0.5uF) the current will be 22mA for the LEDs. with the component tolerance of 20% and the domestic voltage fluctuations the current may shoot to more than 25mA which may kill your bad LEDs. with 3nos 1uF in series the LEDs will get just 15mA which will be quite safe for the LEDs due to the above indicated reasons. May be the brightness will be slightly lower, which you cannot make out.
Hi Mohmmed 0.47uF 42LEDs, 0.82uF 67LEDs, 1uF 74 LEDs of 3.2volt 20mA
Dear Mr.Seetharaman,
Iam connecting 40 LEDs(3.2v@20mA)with above circuit.Please Let me know which is better for following two capacitors?
1. 0.39uF(400V)
2. 0.47uF(400V)
This both are is good or should be better 0.39uF than 0.47uF?
Also I have 500 pcs pack or 1uF(400V) that’s mistakes buy for this circuit. However how that capacitors use with 40 LEDs(3.2v@20mA ? Which value of capacitor for add as parallel with 1uF(400V)?
Please reply me soon. Thanks in advance!!!
@Seetharaman: Thank you very much sir for your Quick reply. However regarding below comment 0.39uF also working fine for 24LEDs(3.2V@20mA) also? Its mean 24 to 40 LEDs(3.2V@20mA)is working fine with 0.39uF?
Please explain this.
Thanks in advance!!!
Mohammed Faiyaz: Thanks lot for your suggestion. When I make fist time this circuit with 24 LEDs(3.2V@20mA), I face same problem & that all LEDs was burned. but After change value of 1uf to 0.39uF, now this circuit working as great.
Regarding use 1uF- its need 72 LEDs(3.2V@20mA)I think. Please see previous comments.
Seetharaman
December 19, 2011 at 4:51 pm
Hi Malli for 24LEDs(3.2V@20mA)of your specification reduce 1uF to 0.39uF, for 48 LEDs reduce 1uF to 0.57uF (0.47 + 0.1uF) for 72 LEDs use the above circuit no other modifications are required.
Hi Mr Seetharaman im waiting for you’re reply i want to know how many 3.2 Volts 20mA LED’s can glow on 0.47uF, 0.82uF, 1uF, Min & Max Qty’s LED’s ? Plz Reply ASAP.
Hi Mr Seetharaman im waiting for you’re reply i want to know how many LED’s can glow on 0.47uF, 0.82uF, 1uF, Min & Max Qty’s LED’s ? Plz Reply ASAP.
KASUN:- I have constructed 27 QTY 3.2v 20mA LED’s with 0.47uF, after 2 days 2 LED’s get damaged and also its getting heat and its too bright, then i have increase from 27 to 39 LED’s now its working fine.
Hi Kasun decrease 1uF 400volt to 0.39uF 400volt no other changes are required
Dear Mr.Seetharaman,
Iam connecting 40 LEDs(3.2v@20mA)with above circuit.Please suggest the required changes.
Thanks in advance!!!
Hi Najimi 4volt is too much for the LED. First check with 3 volts battery how much they are consuming use that figure for calculating the circuit values. they my be 3 volt 20mA LEDs, which will not suit the above circuit. it has to be 3.2 volt 50 to 60mA LEDs. (they are called triple LEDs one encapsulation with 3 LEDs of 20mA each)
Hi,
I need instructions and guidance in replacing 4 volt bulb using 0.8 Amps
I am keen to have a circuit using a cluster of 5 LEDs of 5mm dia emitting
total 30 lumens. Using 5 LED reduces emmission of temp.,so no need for a
heat-sink. The Charging voltage is 6 volts DC, which charges a lead-acid
rechargeable Battery of 4 volts /10 Ampere-hour.
The current entering the circuit is approx 4.1 volts DC and the LEDs’ are
3.2 volts. I have put 10 Ohms resistance in each LED in parralel and they
burn reasonably well. But the problem is when they are switched on and 6 volts DC flows,thereby reducing the life.Seeking higher life of LED.Please suggest some gadget that will last atleast 30,000 hours in
the circuit. Please help. My email : surendra.biyani@gmail.com
sir i bought the led,s from electonics shop 8mm they dont know the led volt and wattage any way i mde modification and i connected it as you told, Each led is showing around 4 volts after 1 minuts all led,s blown how can i know the wattage and volt of the led if i remove the filter capasitor main voltage is showing 92 volot
Hi Seetharaman, i have constructed this with 0.47 UF and 27 LED’s, 20 MA 5mm. its working fine, but little bit LED’s getting heat up what can i do ? and also i want to know how many LED’s 25 ma can glow on 0.47 minimum and maximum quantity plz reply ASAP.
Hi Ronak yes both the 100 ohms to be reduced to 33ohms.
Thank you sir.
Could you please tell me if both the 100 ohm resistors are to be brought down to 33 ohms?
Hi Ronak you have to increase 1uF to 2.5uF 400Volts and reduce 100 ohms to 33 ohms 1 watt. increase 10uF 160 volts to 47uF 160volts.(350volt is preferred if you are likely to disconnect the LEDs, or may get disconnected if they are on a different board)
Sir if I want to use 24 nos. of 150mA(8mm,0.5 watt) LEDs, then what changes do I need to bring ?
Hi Kasun this circuit can feed only 50 to 60mA maximum to the LEDs. For 1watt LEDs use standard drivers of 350mA which can drive 1watt LEDs 3nos in series.
Hi Prasad with standard 50-50 LEDs 50 to 60mA will be the requirment. for 100mA 10mm leds you have to add 0.8uF 400 volt n parallel with 1uF 400 volts, Reduce both 100 ohms to 47 ohms 1 watt
Dear Sir,
If we use 1W(300mA-350mA) LED with this circuit, How much LEDs use with for this?
Thanks so much gave this great circuit for us!!!
Dear sir, if I use 100 mA white LED shall I have to increase the wattage of the resistor and what will be its value? Thanks
Dear Mr.Seetharaman,I want to use high brite white 3.2volt 100mA LED instead of 50mA led.In your circuit you use 50mA led.If I use 100mA led it requires to change the wattage of the resistors.Please let me know the value
hey seetharaman i hav a few questions about ‘battery charger circuit using scr’.i hav left you mail..plz reply fast my submission date is near.plz
sir my 56 LED- lamp was working fine- but 3days before, it went out- the 10uF capacitor had blown and also one LED was gone- i replaced them- today evening, suddenly the light started flickering- flashing in 3-4 flashes per minute- where could be the problem?
Sir if I want to use 24 nos. of 150mA(8mm,0.5 watt) LEDs, then what changes do I need to bring?
oh ok thank you- but they r a bit expensive online and is not available locally thats y.
Hi Philip to a minimum of 1 and a maximum of 6 LEDs in series. If you feel the brightness is little less you can increase 3uF to 4uF. No other changes are required. By adding more LED the current will come down little, you will not be in a position to distinguish the brightness change without the help of a Light meter. For higher current LEDs of 300mA and above, I always prefer a driver which is available for a maximum of 3 LEDs in series, which will give you a constant light output and safe also.
Sir is this for 2 LED’s or 4LED’s?
Hi Philip you have to increase 1uF to 3uF (1uF & 2uF in parallel) and reduce both the 100 0hms to 22 ohms with >2 watts rating. no other modifications are required.
Sir what modifications to be made if i’m using 3.2V, 300mA power LED? I intend to make a 2LED and a 4 LED version.
Dear Seetharaman
I just came across your contribution in circuits today.com website
I have a 23led emergency lamp using a rechargeable battery
Problem the capacitor and resistor in parallel connected to one mains point 230 v has blown out
Cold you pl let me know what are their values.
Early reply requested
Thanks
Mr Datta
Oh Sorry my mistake- I used ordinary ones- triple chip ones are not available here
Hi Philip 24LEDs of 3.2 volt 50mA (triple chip type)is better than 9watts CFL. Definitely something wrong. are you using tripple chip or normal. if it is normal then your eattage will be 3.2 X 56 X .02 that will be 3.6 watts.
Oh 9W? But then an 8W cfl is more energy saving right? it definitely gives more light than this one. Please shed some light-
Hi Philip Congrats. it will be 3.2 v X 56 X 0.05= 9 watts approx. After switching off the current through the LED exponentially redueces hence a faint glow will be seen in total darkness for some time.
Hi its working perfectly now and my night hours will have less impact on electric bill- one interesting thing i have noted is that the LED’s glow for a lil while even after turning the lamp off- i made it the 56 led way- how much power would it be consuming? 78*50mA=3.9 watt?
Hi Philip thank your stars the capacitor should have blown, do not energise without load connected. What you have measured is not the correct voltage, measure only after connecting the load (as there is no zener diode to protect the circuit)it will be around 78volts.
I just tried measuring the voltage b/w the output terminals without connecting the LED’s yesterday- it showed 17V dc and the 160uF cap was heating up- is this normal?
Hi Faiazuddin you require 12volt DC only as three lEDs are connected in series with a current limiting resistance. you can use 12 volt rechageable battery with charger.
Hi Philip you can use 56 LEDs of 3.2 volts 50mA with 1.5uF and with no change in all other components. If you use with 24LEDs all will blow. You can use 2 strings of 35 LEDs in parallel (total of 70LEDs) with 1.5uf.
Hi 1uF poly cap was not available so i got a 1.5uF cap(400 v)- so how many LED’s should i connect with all other components remaining same?
also in the above ckt, how many parallel LED strings can be connected?
Hell Seetharaman i want to do same project with LED Strip is it possible to work,
an i dont know exat details of this LED strip but its work on 12V DC an i dont know what is the power consumption iam uploading the image link:- http://img20.imageshack.us/img20/1195/ledstrip.jpg
is it possible to work on AC current like this components plz reply,
an thanks for earlier reply.
Goodday sir, i want you to send me a schematic diagram using block to describe how a 12v dc power supply may be derived from an ac main source of 240vrms. Please help me out sir
Hi Sankar since we use the Xc of the capacitor, we are concerned with its value and the applied frequency. The voltage choice depends on the applied voltage . here in the above case it is 230VAC. Hence a capacitor of 1uF with an operating voltage of 230volt AC is ideal(unfortunately these capacitors are not readily available in the market) but by calculating peak DC (it is 325Volt)1uF 400Volt (standard voltage range available in the market)can be used successfully.
Hi Sankar as we are using Xc of the capacitor only the value of the capacitor and the applied frequency counts not the voltage. voltage depends on how much we apply. here 230 volt AC is used, you can use 1uF 250AC (which are difficult to find in the market)or to take care of peak voltage 1uF 325volt DC. (the standard voltage available is 1uF 400VDC).
Dear Sir,
Please confirm the type of capacitor that is to be used – 1uFd/ 400 Volts Dc Poly.capacitor or 400 volts AC capacitor. Using different value capacitors will give different voltages as out put. Am I correct?I hope AC Capacitor works more perfectly than a DC capacitor.
Hi Faiyaz the capacitor is 0.1uF 400 volts you have use 5nos in parallel so donot use. Resistances are OK. 0.47uF 250 volt AC capacitor is the right component.Please go ahead constucting the projects you will be sucessful.
Hello Seetharaman, i want to use 24 Led 5mm, as per ur instruction i have to use 0.47uF 400V. but im getting 0.47uF 250V can i use this is it compatible let me know plz reply asap.
an also iam sending components images links,
following components i have got is this ok ?. plz check 1uf 400 & 0.47, 250VAC
1)1uF 400V http://imageshack.us/photo/my-images/213/03052012524.jpg/
2)0.47 250V http://imageshack.us/photo/my-images/440/03052012525.jpg/
3)resistors http://imageshack.us/photo/my-images/171/03052012527.jpg/
Hi Tajinder use the following link for your requirement
http://ixapps.ixys.com/DataSheet/LDS8726-Datasheet-_Rev-N1_0.pdf
Sir,
We are looking forward to assemble led tubelights, would need your help to fix the driver for the same, i intend to use between 240 to 300 smd leds type 3528 each having fv – 3-3.3 volts and Iv – 20mA in my tubelights. Can u recommend me some driver design to run them safely and how many should i connect in series and how many in parallel connections. each of the leds have max. driving current 25 mA.
The design that i am looking forward should run these leds anywhere between 20-25mA constantly.
Thank you
Hi Kosala This can happen if you have used normal 2 pin high bright LEDs, which are meant for 30mA maximum. Now check each LED by supplying from 2nos pentorch cells in series. If they glow alright the problem may be due to capacitor 1uF has become dry or 10uF short or 1N4007 defective. With 2 pentorch supply if LEDs are not glowing check each LED if all of them are damaged check a spare LED with 2 cells and if the glow is ok check the current say if it is 30mA then reduce the capacitor 1uF to 0.47uF 400 volts replace all the LEDs and use.
dear sir…please help me…I made this circuit and after a few days bulbs don’t work please help me…I’m really happy with Ur circuits..so please respond me soon..
dear sir, how much value of resistors should be provided in the circuit for example 220v circuit drops down to 24v how much value of resistor should be provided and how much the wattage is there any specific calculation i dont know the ampere of the circuit
Dear sir
can u send me 36w led drivar circuit diagram input voltage Ac-220 output and i need output DC 42v.
thanks and regards
jitender sharma
I made this and after a few days bulbs dont work please help me…
Hi, If I wanted to use 1.5-1.6V 60mA LEDs I assume I could just double the number up to 48 instead of 24 3V 50ma LEDs to make up the change in voltage between the two types of LED?
Since 48 is a lot of LEDs to blow up in one go if I get it wrong what changes would I need to make if I wanted to use just 24 of the 1.5-16V 60mA LEDs?
Thanks
Hi sir,
For brighter Light I used 55, 3.2-3.6v,20ma cool white led with .47+0.1 µF (0.57 µF). But these are warm @55 °C. These are also not bright enough for small room.
Thanks,
Hi Seetharaman, I have successfully assembled the project and it is working. Thank you for that. There is one thing I observe though which is the LEDs are not bright enough though they are not getting hot. Can you give me some points to check so that at least I could make some adjustments to make it brighter? I wanted it to be as my lamp inside my room. Thank you.
Thanks for reply Sir.
Hi PK standard SMPS for 3 X 1watt LEDs are available the size of the PC is just 10mm/10mm. you can use them they are very in expensive reliable chinese make.
Dear Sir,
Thanks for reply. It seems ok now.
Another question – I got 1 watt LED (3.4 V 300 mA), can I drive one or more of these with 230 V Ac? How?
Hi PK it is OK it can be around 50deg, feel the temperature after using it for 6 to 8hrs if it is warm (check the temp with IR thermometer after switching off) if it is within 50deg it quite OK you can go ahead.
Previously I used 0.33µf+0.1µf but found around same amount of temp so reduced to 0.33µf, but still same temp?
Dear Sir,
I built 3.2-3.6v,20ma 24 cool white led light using 0.33 uf/400v cap, other components as it is.
Using IR temp gun I found around 52 C temperature in LED base, is it normal or I should reduce Cap value ? Other components are normal.
Thanks Seetharaman for the reply. More power!
Dear Readers,
I found this small and very useful calculator,I thought I should share the link here, it might be useful to you.
http://www.electronics2000.co.uk/download.php?source=ea_calc_ad#assistant
Dear Sir,
Thanks for this very useful circuit and satisfying each and every one’s query patiently.
I want to make warm white LED lamps to replace CFL’s in my house, however I could not find resources in India. Could you give me links or shop names where can I find one. Is there anyone having such difficulty?
Thanks Seetharaman! Will update the status soon 🙂 ..
Hi Jeh you can use 600volt capacitor, it may be slightly bigger in size than 400volt one. you are always comfortable with higher voltage capacitors, provided the space is not at premium.
Seetharaman, I was able to order capacitors for C1 in Singapore however it is rated 600volts instead of 400volts, will there be any bad effect?
Hi Jay it is only to discharge the capacitor during switch off. It can be the same value.
Hi Bharath add 0.68uF 400 volt capacitor in parallel with 1uF no other modifications are required.
Hi Asim is your model working, if not some mistakes may be there. If working and getting warmed up it is ok the required rating is only 1/4 watt. Any mistake in the circuit it should burn to protect other expensive components.
Hello sir,
I want to make the DC(12V) to AC(230V) “pure sine wave inverter circuit”. Please if you have any circuit or ideas please mail me or post here. I want the circuit design for minimum 100W power output with 230V pure sine wave.
Please reply me i am waiting for your reply!
-Deepak
mail-deepkajale@gmail.com
Dear Sir,
I have calculated the value for the first capacitor in your circuit (1muF)- however, how do you calculate the resistance values, bridge and the value of the second capacitor?
Looking forward to your response. Thanks!
Hello Seetharam,
If I were to use 60 LEDs of 50mA, what are the modifications required?
Thanks!
100 ohme resistor hot
Hello Seetharaman, Thank you and I appreciate your reply. May I also know if I can use the same value of resistor (220K 1/4w) if I wanted to change the value of the capacitors to be used for LED’s more than 24 nos, say 50 LEDs? Thanks again
Hi Jeh You can try by connecting 2.2uF 600 volt capacitors in series back to back (+ve of both capacitors connected together and both capacitors negative terminals used in the circuit make it 1.1uF non polar)with 220K 1/4 watts resistances connected in parallel with each one of them.
Hi Nagaraj you can submit your comment on the leave a reply coloun with your name and email address which will not be published. you can send your well tried circuits with the prototype’s photgraphs and a detailed write up to Mr. John of circuitstoday through his email id john@circuitstoday.com
Hi Arun Kumar you can use the same above circuit with 60 LEDs of 20mA by repacing 1uF 400volt with 0.68uF (can be 2nos 0.33 in parallel or one 0.47 and 0.22uF in parallel)400volts and 10uF160volts with 10uF 400volts. For 120LEDs use 2 sets of 60LEDs in parallel by using 1uf and 0.33uF in parallel in place of 1uF400volts in the above circuit, no other change is required.
Sir. How Many diodes can this handle? Is there A minimum? I’m planning to use 10 diodes. Thanks!
Dear Mr Seetharaman,
I am an amateur and would like to replace all incandescent bulbs in my home with suitable LED lights.I plan to use 60 and 120pcs of LED’s used in 60 pcs in series and also in 60 x2 configuration (60 in series string and two parallel strings)Each led has Vf 3.2V, If 20mA ,reverse voltage 5V.Can you pls suggest a reliable circuit with values for the resistors and capacitors to be used .
how to comment and upload circuits?
Hello Seetharaman, I have been scouting for 1uF/400v capacitor here in my country but it seems that the only maximum available value we have is 0.1uF. Most capacitor with voltage capacity of up to 600v are electrolytic type capacitor. Could you advice me if it is possible for me to use such polarized capacitor and how to connect it. I am really exicited to assemble this project.
Thank you
Dear Sir
I tried the 24 LED circuit, it is very good and useful in small rooms. So many circuits i examined. I need good brightness to use in my house to avoid CFL. I used 8mm white LEDs. So I request you to send such a circuit and help me. Thank you. Udayan
Hi Yadi it cannot be predicted. you please feel the LEDs for temperature after a glow of minimum 3hrs. if they are warm better to reduce the current else their life will be reduced drastically. if they are cool running it is safe you can use it with 1uF itself.
hi sir,
thank you for your answer. 0,33uF cannot find in local market. i am already assembled 40nos dip 5mm strawhat led using 1uF 400V polyester capasitor, and the led glow very bright. i has been tried in 3 days, and the led is just fine. how long the time the led can be glow using dip 5mm strawhat with 1uF capasitor?
Hi Yadi the maximum value is 20mA at 3 to 3.2 volts.If you use them in the above circuit you have to reduce 1uF 400 volt to 0.33uF 400volt polyester capacitor. no other change is required.
if i want 2 increase the number of led what changes should i bring
hi sir,
what is maximum forward current value for dip 5mm strawhat superbright? because i use this for above circuit, but the led is not broken.
hi sir, very nice circuit,but cap current capacity (100 ma peak ) is greater than and led max currentas u said 50 ma peak ). then how can leds withstand such a huge current.
Hi Rasitha,
Wattage consumed by 24 LEDs @ 50 mA is 3.85 Watts. This is assuming that the voltage drop across each LED is 3v.
If drop across each LED is 3.2v, then wattage is 4.09 watts.
Send me your email address and I will mail you a calculator that I have made for finding Cx, Wattage and current flow thru LEDs.
How is the quality of the output Light. Is it bright enough to light a decent room. I am very much waiting to assemble this ckt.
What is the cost of 50mA LED in your local market?
Seetharaman sir, May the Year 2012 bring for you happiness, success and filled with Peace, Hope & togetherness of your Family & Friends…Wishing you a HAPPY NEW YEAR.
sir,
i assembled the circuit .. It is nice….what about the wattage of this and 50 LED circuit….
Hi Seetharaman,
What is the price of a High Bright White 3v 50mA LED in your local market?
Hi Seetharaman,
These High Bright White LEDs (3v @50mA) are they available in 2 pin or 4 pin or both type packaging.
If 4 pin packaging, how to wire them?
Hi Stanley you have to use both voltage and current peak value to calculate with filter capacitor, or both in RMS value. o.4 is not a standard value you can use 0.39uF which is around 2.5% less but will suit as the current change will hardly be noticed.
Hi seetharaman
What are those resistors for ? Are the series resistors used for surge current protection ? What are the parallel resistors for ?
Hi Seetharaman,
Are 0.4Uf standard cap available?
What combination to achieve 0.4Uf?
Hi Seetharaman,
In fact in many calculations and in your responses to Japanjot, Murali and Rahul, below, you have used 230 volts rms to calculate voltage to be dropped.
Hi Seetharaman,
With regards to your response, I am confused. In all previous comments to Cx calculations, you have said to use rms value of dropping voltage. Now you have responded to me to use peak value. Pls clarify
Hi Seetharaman,
Are 0.4Uf standard cap available?
What combination to achieve 4Uf?
Hi Rasitha increase 1uF to 1.2uF no other change.
Hi Stanley it should be 0.4Uf for 15nos 25mA LEDs,
for 300LEDs of 3volt @ 50mA it should be 9uF. calculate for peak voltage and current as AC is converted to DC. above 108LEDs no capacitor required, better to prvide a 250volt VDR as protection against surges.
Sir,
If I use 100 LEDs of 3volts 50mA rating, then total voltage a/c LEDs will be 300v (100 x3). But my mains is only 230v @50Hz. So logically no Cx required because no voltage drop required. Is my logic ok. If Cx required then how to calculate in this case.
Hi Seetharaman, I have connected 15 LEDs (3volts 25mA) in series using above ckt. Now using formula, I have come to value of Cx as follows. Please let me know if my calculations are right. Also what is the standard nearby value of Cx available.
Total voltage a/c LEDs is 45v @ 25mA (3 x 15). So votage drop required is 185v @25mA (230-45). So R is 7.4k ohms (185/0.025). So Cx is 0.43mF. So what is standard nearby value of Cx
Secondly, If I use 21mA for LEDs Cx comes to 0.36mF. So can I use 0.33mF Cap?
sir,
…….how i can cnnct 50 LED s……to this circuit…what will be changed……?..
Hi Malli check after running for 15minutes whether LEDs are getting heated up. if not no problem. if they are getting heated up reduce the capacitor value to next available lower value. Driving the LEDs with higher current will reduce their life.
Hello sir here the available capacitor are .22 .33uf .47uf .68uf, I tried with .47uf for 24 led and .68uf for 48led its working fine and bright. can i use like this or i have to change. all leds are 3.2v 20ma. if i have to change what should i do pls help me sir
Hi Malli for 24LEDs of your specification reduce 1uF to 0.39uF, for 48 LEDs reduce 1uF to 0.57uF (0.47 + 0.1uF) for 72 LEDs use the above circuit no other modifications are required.
Hi Nishanth you cannot mix up LEDs. same type alone can be used in series. To use 50nos RED LEDs in series use the same circuit reduce 1uF to 0.33uF no other component requires any change.
hello sir,
please explain how to connect 50no’s of LED in AC mains
hello sir,
how can I use five bright LED’s forty five red LED’s in the circuit in series.What changes needed to make in the circuit
sorry sir its 3.2 3.4v 20ma led. not 25ma. please help me
sir i have 3.2-3.4v, 25ma led iam planing to do 3 types of led, 24nos, 48nos, 72nos please help me and let me know what are d changes i have to make in this circuit
malli
Thanks Seetharaman for the unselfish reply/information. May I again ask you a favor if you could publish a transformerless power supply circuit that is connected from the main (240v) and gives an output of 9v dc. This is to be used for IC operated projects like LED Chaser etc.
More power!
Jeh
Hi Jeh you can use 2 capacitors in series, ensure that you use 220k resistance in parallel with each capacitor. (capacitor voltage value will get doubled but capacitor value will get halved if you use them in series).
Hello Seetharaman, We dont have 400volts range. We only have 250volts. Though some electrical appliance use 2000volts. Can I use the 250volts capacity?
Thanks
Hi Jeh what is the maximum value available in your market in 400volts range. if 0.47uF(470nF) use two in parallel.
Hello Seetharaman, Thanks for the reply. I intend to assemble the project that I have bought all the parts except for the polyester capacitor (1mf/400v) which is not available locally. Could you advice me if what could I use as a substitute?
Thanks and more power
what about the bridge rectifier diode number(in4007 ah?)
Hi Hari in this circuit current and surge limiting are taken care by 100ohms before and the one after bridge rectifier plus the filter capacitor 10uF before LED circuit
Hi Jeh the above circuit is the correct one.
Hi Anish you are correct normal LEDs can handle but they get heated up soon . you kindly checkup the temperature raise of LEDs after about a minute of glowing (by using heat sensitive part of your body-may be back portion of palm or face) if it is quite warm, the LED current has to be reduced or you have to use thick large PCB to dissipate the temperature. if the raise in temperature in not taken care the LEDs will fail fast.
Hai seetharaman sir,
My attempt to find whether the LED’s I have are super bright or not:
I do not have a constant current source. So, i used a 5v regulator and 200 ohms resistors which gave around 24mA. Then the voltage drop was around 3.0 volts. When I replaced 200R with 100R, the current supplied was around 46mA and the voltage drop across LED is around 3.15V. How can I conclude? BTW, normal LED’s wont stand more than 25mA i think… Am i correct?
Hello Seetharaman, I was looking/surfing for a circuit for LED and found this site. I read the chain of messages and have read about the circuit diagram which is incorrect. You said that you have corrected on your comment dated 26 June 2010 of which I did not see. May I know if the diagram above is now the edited or corrected one?
Thanks and regards
Hi Seetharaman,
Thank you for the help. One more doubt. There are strong recommendations to use LEDs only with a current limiting resistance(since a small change in V can make greater change in I without a resister in series and harmful for LEDs.) I guess 100E used after bridge to limit surge also acts as a current limiting one. Or do we use one more suitable resistance for current limiting ?
I found some useful information regarding LEDs with FAQ and some wizards to calculate circuit config. at
http://led.linear1.org/led.wiz may be useful for many reading this post.
Hi Hari with 3.2 volt 25mA LEDs it will be 61 volt 25mA. you require only 0.39uF at the most you ca use 0.47uF. with 1uF it will draw >50mA which may damage your LEDs. If you wand Zener protection use 32volt 1watt zener Diodes in series and in reverse bias condition in parallel with 19uF 160 volts against surge (not really required)
Hi Seetharaman
Thanks for your advice. Now I have rewired 19 LEDs in Series, but total voltage is around 60V for 19LEDs(using 1Mf/400V). I guess it is drawing more current, since LEDs are VERY bright.
I invite your attention to your response to Mr. Murali dated October 5, 2010 as…
“Hi Murali for 19 LEDs reduce capacitor to 0.82uF, a standard value or use a 15volt in series with th LED loop.”
You didn’t mention the 15V component, I guess it is a zener reverse biased ? Please clarify.
I hope I can use a 0.33Mf and 0.47Mf in parallel instead of 0.82Mf if available. Here I get only 1MF and 0.47MF/400V capacitors in the local stores and no other value is currently available.
Hi Babla each series requires say 25mA current you require 75mA current. 0.22uF 400volt cannot give you the required current raise the capacitor value of 2uF instead of 1uF(connect one more 1uF 400v in the above circuit. now you are getting only less than 5mA current in each loop.
Hi i connect the 3 cerise of LED each cerise are 50 LED, i connect IN4007 Diode in Bridge & .22uf/400Volt paralal in 110 K Resistance, each cerise 100 Ohm Resistance But do not Glow Bright,Pl. Help me The Circuit & solb the problem
Hi hari for 19 LEDs in parallel it will be 3volts @ 380mA this calls for a 5uF capacitor in place of 1uF 400volts. 100 ohms should be reduced to 33 ohms 10watts. The 10uF should be raised to 100uF400 volts. You have to use 12volts 10 watt zener diode before 7805. no space and not worth the trouble. buy a 3volt 500mA step down transformer and fit it in the space occupied by the battery. feed the transformer output to the rectifier circuit already present. no need for any other modifications. will be most reliable.
Hi Seetharaman,
I have a chinese make LED lamp with 19LED and a 4V battery earlier. Now the battery failed and I wish to convert it to a mains operated lamp. I have modified it with your circuit with an additional 7805 and 47E at the output to get around 3.0V since LEDs are already soldered in parallel. But the input of 7805 is around 32V. what changes should be made to your circuit to get the output voltage around 10-12V so that 7805 will drive safely LEDs in parallel. The LED is small bright white type and works within 2.6-3.0V and 20ma range.
thank you.
Cheap and best. Thank you very much Sir.
Hi Prabhat you ca use 100LEDs of 3volt 25mA standard white LEDs in the above circuit with just one change of replacing 1uF with 4.4uF (2nos 225k 400 volts in parallel)
cant we use this circuit for 100 LEDs?
Hi Asankap it is better to use 400volts if LED chan is likely to have any dry joint or to test power supply portion without LEDs. i prefer 10uF 400volts as filter capacitor
Dear Seetharaman,
Thanks for your reply
i meant the capacitor after the bridge(electrolytic capacitor).most of the manufactures use 4.7uf 400v cap.i use 80leds(40 in series) and 108leds(54 in series).is 250v capacitor enough or 400v one better?
Thank you
Hi Asankap it should be 0.47uF 400 volts not 4.7uF.
Hi Manoj for 9LEDs use o.47uF 400volts inplace of 1uF 400volts no other change is required.
Thank u Seetharaman Sir for a wonderful circuit. Your circuit is excellent and working perfectly. What are the changes made to reduce the LEDs to 9 nos? Hope you will reply soon.
Regards
MANOJ VJ
Read more: https://www.circuitstoday.com/mains-operated-led-circuit#ixzz1XvawVZ92
Under Creative Commons License: Attribution
Dear Seetharaman,
Thanks for your reply.is 4.7uf 250v electrolytic capacitor enough for 80leds(40 in series)?.is 400v better?
Thank you
Hi Asankap for 3.2 volt 20mA LEDs you have to use 0.47uF instead of 1uF. these resistances are for surge current limitting, hence need not be changed. you can use any non capacitor rated for atleast 400volts. 1N4007 you can use PHILIPS ITT EC etc.
Hi seetharaman,
Just a one question.i am using 5mm 3.2v 20ma bright white leds(i drive them at 16ma to get maximum efficiency).What is the minimum safe resistor values for before and after the bridge rectifier(100 ohms resisters)?
Thank you
Hi seetharaman
thanks for publishing such a valuable circuit.i have few questions regarding this circuit.i had a problem with 1N4007 MIC make and electrolytic capacitor.what are the best brands to use in these energy saving lamps?are nichicon and rubycon good?any specific brand for 1n4007?
there are different sizes and type of Metallized Polyester Film Capacitors.(ex:-cbb21,CL21).so,what is the best type and brand for better life
Thank you
Hi Deepak for red LED maximum is 2volts at 35mA better not to drive at the limits may shorten its life.
Hello sir, thank you for reply!
you have given the rating for 5mm Red LED as 1.7V at 20mA
i want to know that whether it is same for high bright Red LEDs which has appearance like white LEDs when OFF and emits high bright Red light when ON. plz reply!
i want 2 channelor 3or,4 channel led power supply,circuit diagram ,,,,,,,,,,plz sirrrrrrrrr,
Hi Deepak 5 mmRed LEDs will be rated for 1.7 volt at 20mA. for 50 LEDs it will be 85 volts. Reduce 1uF 400 volts to 0.37uF 400volts (0.22 in parallel with 0.15uF, 0.33uF 400volts can also be used) no other change is required.
hello sir,
yes sir i want to connect only 50 nos. of red 5mm LEDs (which has clear glass like outer appearance),so please tell mi what changes should be done in above circuit & component values to make single string of 50 red LEDs. Sorry sir, but i don’t know the current and voltage rating of that red LED so kindly request you that suggest me changes.
Hi Deepak you can connect only one colour per string, as the currents are different for different colour LEDs.
hi sir,
thank u for your reply! Sir please tell mi what changes should be done in above circuit & component values to make single string of 5mm 50nos.of white-to-red LEDs. olz give detail of all changed component & their values.
plz reply!
Hi Deepak you cannot mix up LEDs in serial string as their current ratings are different. you can make 5 different colour individual 5 strings and place the LEDs alternately.
Hi Anish feed 25mA from a constant current source, check for the visual brightness and measure the drop across the LED if it is 3.2 or greater then the LED is normal one. If the drop is just around 2.9volt. increase the current to 50mA, the drop across the LED is between 3.2 and 3.4volt visual brightness level will indicate it is hi bright LED. if you have lux meter feed 50mA to the LED keep the LUX meter at 1 meter distance it should indicate between 180 and 210LUX. if so it is high bright LED.
Hi seetharaman,
I am an old(66yrs) electronic hobbyist need your help. On a 8mm white LED packet written fd-3.2 to 3.6volts, wattage-0.25w. What will be the operating current range of the LED’s. Kindly reply soon.
Regards
am choudhary
Thanks Sir. Your circuit is excellent and working perfectly. What are the changes made to reduce the LEDs to 9 nos? Hope you will reply soon.
“RAMZAN GREETINGS”
Regards
MANOJ VJ
Hi Mr.Seetharaman, please do provide a table or something similar so that we can calculate particular capacitance and resistance needed for particular no.of.leds.
BTW i have a bunch of 100 white LEDs So, how do i know whether it is super bright or ordinary LED and how can i estimate its current rating…
Regards
hello sir,
i want to make mains operated lighting for deepawali using led. i want to make —
1)50nos. 5mm white-to-red series led string light
2)50nos. 5mm white-to-blue series led string light
3)50nos. 5mm white-to-green series led string light
so i request you that please tell me all the changes needed to make the all 3 cases i mentioned above. i don’t know the rating of these red, blue & green led’s. therefore i request you that please tell me suitable changes.
waiting for your reply!
Hi Murali increase 1uF to 5uF and reduce both 100 ohms to 33ohms 5watts, increase 10uF 160 volts to 47uF 160 volts no other changes are required
dear sir i want to connect 3 high power led of 3.2v of 350ma pls tell me what r d changes is requir in this circuit
Hi Rohit 56 nos LED 56 X 3.2 is 179.2 volt hence you have to use 250volts capacitor before 160volt is getting blown up.
Hi Capsun In the above circuit you can use 250volts are higher voltage capacitor
For 45 LEDs of 3.2 volt @ 20mA use 0.47uF instead of 1uF. no other change is required.
Iam connecting 45 LEds (3.2v @20mA) .Please suggest the required changes .Thanks in advance
Dear Sir I could only find 10 micro farad 250 vols in my place . Can i use this 10 microfarad/250 volts capacitor .Waiting for reply
Hello Seetharaman,
I made this circuit, with the following changes
-56 nos white led used 3.2v 25mA
-0.47Uf 400v against 1Uf PPC.
-All other components remained the same, the LED’s light up etc., Is this circuit okay, I figure that the 10Uf 160v will not last long, cause I find it getting warm.
Kindly advise.
Thank you sir.
Thanks Sir.
Hi Chetan you can use 10uF 400volt.
Sir, in my circuit the 160 volt 10 uF capacitor has bulged on the top, so can I use 400 volt 10uF capacitor I have found that capacitor in the electronic choke of tube light.. can I use that capacitor.