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Iceland
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Hello.

I have a question about a project that I am starting.

What I have
5 meters of led strip (http://www.sparkfun.com/products/10260)
14.4V power supply
Arduino

What I need
I want to let the arduino to set 0-12V (variable voltage) to each R/G/B wire, by using external power supply.
Because the whole chain takes 6000 mA @ 12.0V

What I know
The PWM ports can only output 0-5V, and 60 mA per channel.

Can anybody direct me to the right direction, which components are best here?
Linear Regulators, Shift Register or what.

What is the easiest way?
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Seattle, WA USA
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Quote
What I know
The PWM ports can only output 0-5V, and 60 mA per channel.
You might want to check this fact. The recommended upper limit is usually 40mA, with 20mA being recommended for long term use.

You can use a transistor to control each leg. Transistors can toggle at PWM speeds, and can control that amount of current.
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I don't think you connected the grounds, Dave.
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Quote
The PWM ports can only output 0-5V
sp. "The PWM ports can only output 0 or 5V"
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Iceland
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Whoops... thanks for the correction.

so a PWM pin set to 50% duty cycle, connected to transistor and external power supply, should give me 50% brightness on led strip ?

How do you hook up an transistor to external power supply?
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Johannesburg. UTC+2
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How do you hook up an transistor to external power supply?

.... like this
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Iceland
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Can these transistors, like BC546, hold up to 2A@12V ?

the datasheet says 100 mA / 500 mW.

Any other solution ?
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You'll need to look at the datasheets for various transistors...
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