Linear has a post @ [H] forums about an LED fade circuit, it links to http://ourworld.compuserve.com/homepages/Bill_Bowden/page5.htm , I'm not circuitly inclined, so I tried to use a dumbed down version, found here; http://www.metku.net/index.html?sect=view&n=1&path=mods/colorfade/index_eng ok, I've got the components, I'm using 3 AA batteries for power in series; (4.5 volts) I've got all the correct resistors, I have a 33microfarad cap, and a bunch of blue LEDs, the LM324 quad op amp, and 4401 and 4403 PNP and NPN transistors, but no matter how hard I try, I can't get the LEDs to fade out of phase with each other. A computer engineer on our floor actually got one to fade, but he was using a different part number than I was for the NPN transistor (2n2222, I believe) . Also, I want 4 LEDs to fade in unison out of phase with 2 other LEDs; is that possible with this circuit? can anyone gimme some help with this circuit? how would I go about trying to trouble shoot to begin with? I have a digicam, so I could take pictures of it, but I think someone with a schematic might be a little more helpful, if that is the problem. Thanks a lot XtuRmN8r
If you want one set of LEDs to be 180° out of pahse with the other, then connect one set at pin 1 and the other at pin 7, properly boosted with a transistor.
could you elaborate? perhaps a schematic pretty please? like an transistor (will 33 microfarad work) then split into 4 LEDs (properly resisted)? I assume you mean pins 1 and 7 on the LM324? Thx XtuRmN8r
