Robertc65 Posted August 18, 2005 Author Report Share Posted August 18, 2005 So how much voltage will be going to my LED in this type of circuit while using a bridge. I don't see anything here that limits the voltage down to below 10Volts or so? I quess I just don't understand. Quote Link to comment Share on other sites More sharing options...
Guest Alun Posted August 18, 2005 Report Share Posted August 18, 2005 You don't need to limit the voltage to an LED, just the current an LED always has a constant voltage drop across it just like a normal diode except it's 1.9V or 3.5V instead of 0.6V. Normally a resistor does this but with AC a capacitor can be used as it has an impedance and limitts the AC current. By the way but even though I got away without using a 1k resistor (to limit the surge current) when I used my circuit to power a high brightness LED I would recommend you add one as some LEDs might be more sensitive.VLED can be normally ignored as it's quite low compared to the mains v oltage but if you want to power more than 10 3.5V blue LEDs in series then I recommend you take it into consideration. Quote Link to comment Share on other sites More sharing options...
Robertc65 Posted August 19, 2005 Author Report Share Posted August 19, 2005 Thanks for all of the ideas. That is just what I need. I must be brain dead. I'm was not thinking that an LED is really a diode. I don't have to be concerned about the voltage drop. I have a 6 week old baby at home who has proven to be nocturnal. As a result I have been very sleep deprived lately. Sorry for the confusion. You guys are a great help. Quote Link to comment Share on other sites More sharing options...
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