3694Views10Replies

Author Options:

How to connect 10x 10W Power LED? Answered

I have 10x 10W LED, vf = 9V and fc=600mA.

I planned to conect them 2 in a row and 5 rows in parallel.

From this, i know that the overall row Vf = 18V and fc=600mA
overall current drawn from the source = 3A (min)

I plan to use 24V source to power this circuit, anyone can kindly advise me,

1. How I ensure the current into each row is constant at 600mA?
2. do I need voltage regulator or just a power resistor connect onto each row will do?

anyone pls kindly advise.. Thanks a million

PS: Happy new year to you all

10 Replies

user
acidjc (author)2011-01-02

Thanks all for your kind advise, I planning to use this

https://www.instructables.com/id/Super-simple-high-power-LED-driver/

any advise will this good enough for my 2x 10W running at 600mA , 24V DC supply

I computer to use a 2ohm 1W resistor + a LM317, as according to the instruction stated in the link above.

Select as Best AnswerUndo Best Answer

user
frollard (author)2010-12-30

Don't just use a passive resistor for 10 watts of power - you're burning off a quarter of the power to get down from 24 to 18, and it will vary with temperature. Resistor = bad!

Use a constant CURRENT source that self-adjusts to allow for temperature and voltage variation.

https://www.instructables.com/id/Circuits-for-using-High-Power-LED-s/

Step 6/7 has several...they advise (as always) find a power source that CLOSELY MATCHES your sum led forward voltages! Otherwise, you're just wasting power.

Select as Best AnswerUndo Best Answer

user
steveastrouk (author)frollard2010-12-31

TO be honest, though clever, the circuits in there don't address the dissipation issues. For efficiency, and to be true switch mode, you need to use an inductor in the circuit. I have one or two designs I am going to put up on here sometime.

Select as Best AnswerUndo Best Answer

user
frollard (author)steveastrouk2010-12-31

tis true -- they still rely on good source choice to reduce waste -- but they do provide protection from the perils of over-current -- the cheapest win-lose scenario that is easy to pull off. True win-win (as described in the ible) requires smart switch-mode electronics, and more skill than most people have.

Select as Best AnswerUndo Best Answer

user
steveastrouk (author)frollard2010-12-31

Granted. Its not actually hard, using National's Simple Switchers to make a constant current drive - I've done it myself. Linear do a really nice driver for 3V LEDs, it needs their chip, and an inductor !

Steve

Select as Best AnswerUndo Best Answer

user
frollard (author)steveastrouk2010-12-31

I really can't wait to see your incarnation! I've been hankerin for a smps that is accessible to 'us' :)

Select as Best AnswerUndo Best Answer

user
aelias36 (author)2010-12-30

Google is your friend. I've already used it for you, though:

http://led.linear1.org/led.wiz

You only need LEDs and resistors.

Select as Best AnswerUndo Best Answer

user
frollard (author)aelias362010-12-30

not for ten watt leds -- it gets too complex on these huge ones: the logistics of small leds make it feasable to just use a resistor -- on big leds, you're asking for trouble using a big resistor.

Select as Best AnswerUndo Best Answer

user
aelias36 (author)frollard2010-12-30

Oh, sorry! I misread. I thought it was 10 *mW* . My bad!

Select as Best AnswerUndo Best Answer

user
frollard (author)aelias362010-12-30

yeah, easy mistake - its what I thought at first.

Select as Best AnswerUndo Best Answer