The post explains a simple transformerless SMD 5630 type LED tube light circuit which can be built by anybody for illuminating home interior cheaply. The idea was requested by Mr. Smeet.
Technical Specifications
I am a very big fan of your website and it has been much helpful to me in my college projects i wanted to design a driver to drive 1 to 50 SMD 5630 LE and input voltage 110 to 235 v , forward voltage of LED is 3.3v and i need a very efficient circuit i.e all LED should be maximum brigh would u please help us with this circuitlooking forward to your reply soon
thank you
The Design
The LED model shown below is the 5630 type surface mount LED from Samsung which has the following typical voltage and current specifications:
Forward voltage: 3.3V
Optimal Current: Between 50 and 150mA
Power dissipation: 0.5 watts approximate.
Although it is recommended to operate any LED via a current controlled SMPS, for simplicity sake the following compact transformerless power supply may be tried and could prove as good as it's other counterparts.
The present design is based on my previous variable transformerless power supply design, which enjoys a novel crowbar network concept for safeguarding the involved sophisticated devices.
The proposed 5630 SMD LED driver or compact tube light circuit may be understood with the help of the following discussion:
Circuit Operation
The input capacitor which is a high voltage metalized polyester 2uF/400V rated capacitor drops the mains 220v to desirable limits and feeds the connected the bridge rectifier stage.
The bridge rectifier in conjunction with the 1uF/400V rectifies the AC into a 330V DC.
This high DC is applied across the crowbar network comprising the zener, MOSFET and the preset in the stage.
The preset is appropriately set such that the the output matches the total forward drop of the connected LEDs.
If 50 LEDs are connected in series at the output the above preset must be selected to produce precisely a voltage of around 50 x 3.3 = 165V
Once set, this voltage gets clamped and never exceeds even under worse conditions.
The LEDs thus stay safeguarded from all possible high voltage and surge current hazards.
This happens owing to the fact that the mosfet tends to conduct and ground the output voltage whenever the voltage across its drain/source tries to rise above the set value which may be 165V as assumed here.
Other different number of LEDs may be opted for at the output as per individual preferences, and the preset set up as per the calculations discussed above.
In the shown circuit diagram all the LEDs are connected in series to form a chain of 50 LEDs connected one behind the other with anode of one LED connected to the cathode of the other, and so on.
NOTE: Please connect a 50 Ohm / 1 watt resistor in series with the LED chain for better safety of the LEDs
Circuit Diagram
THE WHOLE CIRCUIT WOULD BE FLOATING WITH LETHAL MAINS AC, EXTREME CAUTION IS EXPECTED FROM THE USER WHILE TESTING THE CIRCUIT IN AN UNCOVERED POSITION.
Feedback from one of the dedicated readers of this blog, Mr. Raghavendra Kolkar:
Hello sir good evening, thanks a lot for sending the circuit diagram of led driver. After 5 failures finally the circuit was successful.
I am sending you the picture of the driver and working.
Thanks a lot, so far all your circuits are working well and nice.
Hello there,
I love your page and I’ve learned a lot about LED drivers from it.
If I could ask for some help, I’m using SMD 5630s with a 5V battery source. Is it safe to use the designs you’ve explained before (https://www.homemade-circuits.com/automotive-led-driver-circuits-design-analysis/) or do SMDs require a little different consideration?
I’m using 20 in parallel to make a head light on the front of a bicycle. I also wanted the design to have two settings, high and low, which I assume could be done with PWM, but I’m not exactly sure how without just buying an IC driver.
Any advice on this?
ECE Student Eric
Hello Eric,
Yes the current controllers explained in the article can be used for making your bicycle headlamp. There is nothing critical about SMD LEDs except current control, and heatsinking if the LEDs have the tendency to become hot.
I actually have an article on this which you an refer through the following link. PWM can be a complex circuit, instead you can simply change the intensity by toggling across a couple of current limiting resistors. This design is also discussed in the following article:
https://www.homemade-circuits.com/making-led-halogen-lamp-for-motorbike/
Hello mr swagatam.
This is my first message to you. I saw your page a day ago. A very beautiful and outstanding page. I am 60 years old. I am an electrician. Let me call you brother and the one who made us love electronics.
I wish you continued success.
Kenan PEHLİVANOĞLU from Turkey.
Thank you so much Kenan, and welcome to this blog! I appreciate your kind thoughts.
Hi brother, i have a 30 0 30 ac audio amplifier Transformer after rectification i got 46 volt dual supply dc, but problem is most of the audio amplifier board is working 24 o 24 volt, dc to dc converter is most expensive, how to reduce the voltage 46 to 24 using resistors, u have a time tell me a advice, thanks
Hi Senthil, using resistors may not be possible, since the current will be too low then and the amplifier won’t work.
You will have to build a buck converter circuit, as discussed in the following article:
DC to DC Converter Circuits using SG3524 [Buck, Boost Designs]
However, even the above circuit is rated to wok with a max 40V , so 46V will be too high.
The best way is too buy a 15-0-15 trafo and use it directly for the amp
Hi, I would like to power some of these 5630 leds to use as a grow light for tomatoes, but I would like to avoid to make myself a high voltage system. So I wanted to stick with 12 or 24v power supplies. However, now I really don’t know how to make it so that I can f.ex. wire a maximum amount of leds to power them with a 12v 2a adapter which are common, or for a 24v power supply if that one suites better.
I looked at this post but I’m still not sure how to exactly do it https://electronics.stackexchange.com/questions/207087/how-many-smd-5630-leds-can-i-power-with-12v-1a-power-supply?rq=1.
Do you have any idea on how this could be done efficiently?
Hi, Assuming the LED is 50 mA, 3.3 V each, you can connect the 3 to 4 LEDs in one series, and use 3 such strings in parallel.
If your 12V is very constant, then you an put 4 LEDs in series, and use 3 such strings in parallel with the supply, without any resistor
If the 12V is not constant, the you can add 3 LEDs in series, and 3 such strings in parallel.
This will require a resistor in series with each of the strings.
Resistor value will be R = 12 – 9.9 / 0.05 = 42 ohms 1/4 watt
I want triac spification for led tube light driver or triac model number.
you can try BT136
I have 165 SMD led connected in parallel and every 5 in series so I need a voltage drive with 400 volt Dc output and my input is 220 V AC. How I can change the above circuit to fit my case thanks.
You can use the first circuit from the following article:
https://www.homemade-circuits.com/how-to-make-led-bulb-circuit/
you will have to first adjust the output voltage to match the FWD voltage of the 5 SMD LEDs in series.
My SMD Led forward voltage is 12 Volt and I have a group of 5 leds in parallel connected in series with another 5 Leds till 165 Leds so I need input voltage of 400 Volt DC.
Please If you can clarify more how I can make the circuit fit my case with a source of 220 volt AC.
Sorry I was wrong un the first comment here I clarify I have 165 SMD led with forward voltage for every Led 12 Volt they are connected every 5 Led in parallel and in series with another 5 leds till 165 led so I need input DC voltage 400 Volt DC and my input AC is 220 volt So I need circuit that Can do this job and have surge protection from overvoltage and overcurrent and I don’t have a problem if the circuit is a bit complicated. Thank you
You can try this, and check how the LEDs work with this set up:
thanks very much
yes obtain my desired voltage by adding a resistor to the circuit above know how to add drive to protect the leds from over voltage and over current.
Do I connect the output of this circuit to the circuit above ?
If yes please tell me how ?
Thanks
I mean by my last comment that I obtained the desired voltage 400 volt by the circuit you post here by adding a resistor. BUT know how to protect the leds from overvoltage and overcurrent to I conect this cicuit to this https://www.homemade-circuits.com/how-to-make-led-bulb-circuit/
If yes please send me how
If know please send me how I will do it
Thanks again
If the current rating of the LEDs is over 50 mA, no current limiting will be required since the circuit can provide 50 mA max.
Over voltage can never happen, since the input is 220V.
Please specify the current rating of the LED module
The rating of one SMD led is 12 Volt 75 MA.
The hole circuit need 400 volt 0.375 A.
For 0.375 Amp the capacitor values will need to be increased to 4 uF/400V each
Hi
What should i do to powering 200 5630 leds with this circuit? I think that i must change resistor of triac… right?
Hi, actually for long LED strings a triac controlled output is simply not required. The surge can be controlled using a resistor, a NTC or an MOV. You can configure it as explained in the following articles:
https://www.homemade-circuits.com/simplest-100-watt-led-bulb-circuit/
Assuming you have 220V as the input, You can make two strings having 100 LEDs each with a calculated limiting resistor, and aditional protection such as an NTC or MOV:
I am operating 1w 3LEDs by Nokia Mobile standard battery. When I connected to the LEDs about 1 yard far, the brightness is optimum but about 12 yards far the brightness is not optimum.so I am guessing brightness is decreasing with distance. How can solve that issue???
you mean to say when LED wire length from the battery is increased, brightness goes down?? then make sure the battery is close to the LEDs
Yes u got my problem but the LEDs need to keep 12 yards distance from battery with circuit for lighting the outer space. Please suggest me alternative way. If I connect capacitor 10v 1000uf in LEDs positive and negative then that situation will improve??
There's no solution to this except keeping the battery near to the LEd, because as the wire length increases the resistance offered by the wire also increases causing a proportionate amount of decrease in the current for the LED….
If I increase positive's wire gauge or both then it can develop the situation??
I don't think that will do any good….the distance which the electrons have to cover is causing the issue
Hello sir,
I am Tanuj, from KOLKATA. Can you please tell me how many 5730 smd led is connected in parallel or series with transformerless power supply? The power supply made by 1uf/400 volt capacitor with paraller connected 1M resistor.after that adding bridge rectifier and zener diode.
Hello Tanuj, it will depend on the output voltage setting of the power supply…..divide the output voltage with 3.3V, that will give you the number of LEDs that could be accommodated.
Hello swagatam,
I want to drive 90 5630/5730 leds using this circuit.
(I wanna drive each at these specifics Vf=3.3-3.4; If=130-150mA)
Considering forward voltage drop of 3.4v per led the total would be 3.4×90=306v.
Without the dropping capacitor c1, the direct rectified dc voltage for 220-260vac would be between 310-370vdc.
So safe consideration would be say 350vdc.
With 350Vdc as Vs and voltage drop of 306v(with If=140mA) for the leds a 300ohm resistor could be used for the led string.
Now i wanna know if the above circuit will work with these specs and what changes would be required to be made to your circuit ?
Also where do I shunt a mov for surge protection ?
Looking forward to your reply, would really appreciate it.
Hello Jeremiah, without C1 your LEDs will not last long…so C1 is a must.
for getting 150mA you may have to use a 4uF/400V capacitor for C1
for yout application you can ignore the triac circuit it wn't be required….instead use an 10 ohm NTC in series with the input capacitor for arresting the initial surge currents.
Hey,thnx fr the reply…
Btw, Will the circuit give out the needed 306Vdc
Also does using much higher rated capacitor(1.2kv) change the output ?
I'm unable to find a 10ohm.ntc, can I use an mov?
yes the discussed circuit will be able to provide the required amount of voltage which will equal to the input supply limit….1kV indicates the breakdown limit of the cap, the output can be never above the input supply level
NTC is better suited than MOV for this application, you can try a 5 ohm NTC
Will 10k BTC work??
Also,, can I use two 5ohm ntc in series?
you can put two in series but a single 5 ohm will also do!
Thnx fr the reply… Will test test it out and revert…