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Unread 29-01-2006, 20:34
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Al Skierkiewicz Al Skierkiewicz is offline
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AKA: Big Al WFFA 2005
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Re: [Help] OI Modification

Quote:
Originally Posted by BrianBSL
You decide how much current to give them, based on the resistor size you use in series with it. But at 10mA, you are not going to get more than 1 LED unless you use a larger resistor and thus have the LED be less bright. Some "bright" LED's produce their rated intensity at a forward current of 20mA or more, sometimes even in the hundreds of mA for very bright LED's (although this is extremely rare).
I think it is important to make an explanation here for casual observers. The LED outputs are switched to the 5 volt power supply through an internal resistor. This resistor will correctly limit the output current to 10 ma when connected directly to an LED (without a resistor).
From the OI Reference Guide, p.5, "The LED drivers provide 5V that is current limited to 10mA. Connect the LED’s anode to the desired LED drive pin. Connect the LED’s cathode to any ground pins."
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Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.