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Transformer less 6v smd led driver circuit? Answered

Hi, I have buy a 6V smd led board which have12leds. Now I what to make a cheap transformer less power supply that light it in 220v ac  mains. I try with a 474k capacitor with 100k resistor parallel and 4 dioads and  a 1k resistor connect to the positive dc output . It works but the light of led is too low. I want a circuit  like in led bulbs to drive them. Thank you.

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rickharrisBest Answer (author)2016-07-16

It will be cheaper to buy an LED lamp with a switched mode power supply and take it out. You will not be able to buy the components for less.

You will also get something that works. It isn't possible to fault find your circuit remotely.

Working with mains electricity is dangerous - 240 volts can and will KILL.

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Soumojit (author)rickharris2016-07-16

I am working on a new project to make a led bulb with old bottles. Can
you provide the circuit. I want to make by own and I know what is ac
mains and I already make things that work on AC mains

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rickharris (author)Soumojit2016-07-16

The web is awash with LEd driver circuits. No point in my repeating things - use google.

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Soumojit (author)rickharris2016-07-16

Just tell me a thing if I connect my 6v led to the videos 12V led circuit will it work? I dont want to blow it

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rickharris (author)Soumojit2016-07-17

Now your lack of knowledge is worrying. NO you can't connect 12 volts to a 6 volt LED panel . Your panel has a designed voltage and current to operate successfully - This should be stated.

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Soumojit (author)2016-07-20

I success fully drive the led with transformer less power supply

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iceng (author)Soumojit2016-07-20

Congratulations !

What is your mains 220VAC 50~ ?

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iceng (author)Soumojit2016-07-20

As one experimenter to another let me help you continue your work .

Sooner or later you will be testing new devices and will for ease of work on live circuits ! . . . That's QK . . ..... . BUT follow this ONE RULE ! ! !

_____________When you touch a live circuit__________________

ALWAYS Keep One Hand in your Back Pocket

_____________________That__is__ALL_____________________

When you do that, electricity will never stop (Fibrillate) you heart...

Neat .... isn't it .... A simple action that keeps .........you alive..

Just for me .. as you read this ... right Now ..

Please put your left hand in your back pocket ..

and wave to me with your other hand..

Best Regards..

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Soumojit (author)iceng2016-07-21

Thanks, but how this happens and can I touch live 220v?

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iceng (author)Soumojit2016-07-21

To get a SHOCK which is electric current to flow through your body there must be an entry point and a leaving point.

Every day you see birds landing on a power pole bare "hot" wire with no harm... That is because only one point of contact and no current can flow... A larger bird with a long wing spread that touches the other wire will die instantly.

I Never try to touch a "hot" wire ... but it happens and then my shoes are good insulators up to 300 VAC and I'm just as safe as that bird with my other hand in my back pocket.

As you get more into electronics you will be making capacitor, resistor adjustments and using clip cords on a live circuit where you accidentally touch a hot wire. With one hand in your pocket you will survive like the bird.

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Yonatan24 (author)2016-07-16

Why not buy a power supply? I think it would be cheaper and easier to use :)

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Soumojit (author)Yonatan242016-07-16

I am working on a new project to make a led bulb with old bottles. Can
you provide the circuit. I want to make by own and I know what is ac
mains and I already make things that work on AC mains

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rickharris (author)Soumojit2016-07-16

Videos and ccts for LED driver are all over the web so no need for me to repeat things.

Use at your own risk - I have not tested the above cct.

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Soumojit (author)rickharris2016-07-16

Can it work with my 6v led and another thing in this video he use make a 1mf non poler 400v capacitor. I have a capacitor 155J 400v should this work?

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Downunder35m (author)Soumojit2016-07-17

You have to calculate the correct values.
But is it really that hard to use Google these days????

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rickharris (author)Soumojit2016-07-16

As I and others have said designing switch mode PSU's is not a trivial task and potentially dangerous. personally I am not happy to offer detailed advice to someone remotely where I have no control over what they do or how they do it.

You should look for local expertise or better still buy a suitable power supply.

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-max- (author)Soumojit2016-07-16

If you choose to build the transformerless power supply, then you must be aware of it's shortcomings and more importantly it's dangers. Capacitors, although appear to act like open circuits with DC voltages, they do act like frequency-dependant resistors with AC power (if you want to know more, google up some stuff on impedance and reactance). High value capacitors or smaller capacitors with higher frequency AC applied can conduct lethal currents. Furthermore, when some capacitors fail, they may fail short-circuit, allowing maximum current flow until something gives out and explodes.

It is important to use class X or class Y thin-film type capacitors, and take care to not get too poke around with a transformerless power supply. That said, when made properly and carefully, transformerless supplies do work well for LEDs, especially if you are willing to accept some flicker.

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iceng (author)-max-2016-07-16

+1

This style design is lethal (kill newbies) and power line fluctuations destroy the LED. https://www.instructables.com/id/Transformer-less-1...

Better to buy a small mains wall wart like Yonatan suggested...

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