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I'm building an LED Lamp and need some advice?

Hi
I am making a lamp using 7xLED lights @3.2v =22.4v
I Aim To Use A 24V Transformer But Need A Resistor To Soak Up The Remaining 1.6V.
Can You Advise Which One Is Suitable And How This Is Installed In The System?
Thank You

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Comments

July 4, 2019 07:10

The commercial transformer work by supplying a constant current so as long as your LED voltages add up to less than the maximum output voltage they will drive the load without a dropper resistor. Here is an example of 350mA LED driver which will drive any series connected LEDs requiring 2.5 to 24V
The summary data states 1 to 6 LED's though, so it may not be suitable for 7 depending on the LED spec over temparture and tollerances.
https://uk.rs-online.com/web/p/led-drivers/7377060/
This part does not specify any typical number of LED's driven but can go to a higher voltage so will drive 7 or more.
https://uk.rs-online.com/web/p/led-drivers/7805789/
So the real question is 350mA a suitable current?

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July 2, 2019 11:55

I don't have the transformer yet so advice on type, model etc and whether i require a resistor would be much appreciated .Thank you!

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June 20, 2019 07:36

What is the transformer you are planning to use? Is this a special LED driving transformer? If so you may not need a resistor in series.

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July 2, 2019 11:55

@Boss Thank you for your response. I haven't got the transformer yet, advice on type and make etc would be much appreciated.Also whether i need a resistor and if so can you advise.Thanks again!

July 3, 2019 07:02

@MichaelStockman