LED help (resistor or driver)

[z_bobbygs13]

I want to build an L.E.D. that has 20 lights

1 watt

300ma

2.4 vf

I've got diagrams that show how many lights in series and parallels and the resistors I should use, but I want to know if a driver would be better and if I use a driver that outputs more volts that my leds would I still need resistors. I would need a 48 volt driver but if I use a 50 volt driver do I need to use resistors to handle the two extra volts?

 

[ngwanhoe]

I am doing one too and find out its not as simple as you think.

If use driver no need resistors under normal circumstances.

Leds needs current Amp to run efficiently not voltage.

I have made a mistake purchacing a step up driver from 3vdc (2 x AA Batteries) to 15vdc and the leds light up but the light is not bright. Found out later that yes volt is enought but current (Amp) are not.

Normally a 3w Led needs 0.35 - 1a which brightest at 1a. I tested 4.8v to a single 3w Led and its very bright, registering 0.9a on meter or tester.

So put high power batteries using resistor or driver.

Best using driver because can help save energy and prolong led life.

Cheers

 

[onetrickpony]

We need to know your input voltage and what kind of supply it is. SLA battery, lion, nimh, or AC? Most important is the voltage.

There are soooo many ways you could do this it's actually going to be pretty easy. The more leds you are planning on using, the more options you have in your circuit.

Give us a little more info and I'm sure I or someone else can help you out.

 

[doctaq]

it depends on how much your leds costed, if you dont care about them much, you can just step down with a resistor but a driver will make it more reliable, if you have a driver you will not need to worry about what the exact voltage is as long as it is within range of the driver