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BrianG · 04:44 PM

Regular LEDs typically need ~25mA to achieve full brightness. This is accomplished via a current-limiting resistor. Failure to use something to limit the current will result in them burning up, short life span, etc. I suspect the only reason they aren't burning up on you the way they are set up is because you have two in series, and each typically has a Vf of ~3.5v. Well, the BEC's 5.5v is not enough to fully turn them on, so that limits the current.

Here is a page I recently created for just this sort of thing. Be sure to read the help thingies because there is a lot of info there: http://scriptasylum.com/rc_speed/_led.html

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BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	01.28.2010, 04:42 PM Regular LEDs typically need ~25mA to achieve full brightness. This is accomplished via a current-limiting resistor. Failure to use something to limit the current will result in them burning up, short life span, etc. I suspect the only reason they aren't burning up on you the way they are set up is because you have two in series, and each typically has a Vf of ~3.5v. Well, the BEC's 5.5v is not enough to fully turn them on, so that limits the current. Here is a page I recently created for just this sort of thing. Be sure to read the help thingies because there is a lot of info there: http://scriptasylum.com/rc_speed/_led.html Last edited by BrianG; 01.28.2010 at 04:44 PM.