Howdy folks. I've done a bit of reading about wiring LEDs but for some reason things are just not clicking for me. So, perhaps with a little bit of proper direction and some tips maybe I can get my LED wiring project for my upcoming case mod completed. The plan: I have a etched acrylic window. I would like to use this window in my upcoming case mod. I would like to mount LED's at the top and bottom of this window, you know, make a little groove and stick the LEDs inside as to light up the etching on the window itself. I would like to use one, or two if absolutely necessary, of my PSU's 12v molex connectors to power the LEDs. I'd like to attach LEDs, 5 at the top, and 5 at the bottom and hope that it gives sufficient amount of light to properly illuminate the window. I'll be using red LEDs as it is meant to mock one of the neon bar signs. The problem: Well.. basically I am not understanding how to wire this. Or maybe I'm just doubting myself cause I don't know much about this subject. What it seems like to me I'd connect a wire to the positive rail of my 12v molex, run it to the positive LED connection, out from negative connection to next LED positive connection, making it's way though each then back to the negative of the 12v molex? And since I'd be using 2 series of 5 LEDs I'd have to use a 100ohm resistor after each series of 5? So 12v positive to LED positive, from LED negative to LED positive, for the series of 5 LEDs, then to 100ohm resistor, connecting both series of 5 LEDs together after the resistors, then back to 12v negative? If anyone could help me figure this out I'd really be grateful.
"So 12v positive to LED positive, from LED negative to LED positive, for the series of 5 LEDs, then to 100ohm resistor, connecting both series of 5 LEDs together after the resistors, then back to 12v negative?" Yes, you got it. We expect some pics when you are done.
"So 12v positive to LED positive, from LED negative to LED positive..." +12V to LED anode, from LED cathode to next LED anode... The cathode is the pointed end on the symbol, sometimes shown with a + sign (especially on rectifier diodes) but connecting it to a positive supply won't work. That end of a diode becomes a positive terminal when the other end is connected to an AC or DC supply. On a round LED the cathode is the shorter lead near the flat on the flange. +12V-----anode---->|---cathode---
have you seen this site? http://led.linear1.org/led.wiz I fed it your series with specs for some 3mm red leds: 2v forward voltage, 20mA forward current. It says yes to your resistor calculation, and shows the following schematic (though prettier on the wizard page itself, it didn't come through on a copy.) Solution 1: 5 x 2 array uses 10 LEDs exactly +12V + -|>|- -|>|- -|>|- -|>|- -|>|- -/\/\/\- + R = 100 ohms -|>|- -|>|- -|>|- -|>|- -|>|- -/\/\/\- R = 100 ohms The wizard says: In solution 1: * each 100 ohm resistor dissipates 40 mW * the wizard thinks 1/4W resistors are fine for your application Help * together, all resistors dissipate 80 mW * together, the diodes dissipate 400 mW * total power dissipated by the array is 480 mW * the array draws current of 40 mA from the source.
