I just made a 3.6v mod with led, is it necessary to use the 470 ohm resistor on the led?
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Yes, more than likely you will need a resistor, but what value resistor varies. If you use the LED calculator in the link below, there are 3 values that you need to know:
1. Power supply voltage (yours is 3.6 volts)
2. Voltage Drop (or Forward Voltage) of your LED
3. Current Rating of your LED
If you open the below link and hold your mouse cursor over the blue question mark ( ? ) another box will open up to show you the most common values to use. Enter the appropriate values then select Design Circuit.
LED Calculator
1. Power supply voltage (yours is 3.6 volts)
2. Voltage Drop (or Forward Voltage) of your LED
3. Current Rating of your LED
If you open the below link and hold your mouse cursor over the blue question mark ( ? ) another box will open up to show you the most common values to use. Enter the appropriate values then select Design Circuit.
LED Calculator
Thanks shortstuff116
Just as a general rule, a supply voltage of 5 volts needs a 150 ohm resistor for most leds. However, we tend to be talking about 4.2 volts max for a single li-on cell, so 100 ohms works well for max brightness on most leds. If you use a blue or white led, then the resistor can be 47 ohms, since the voltage forward is about 3.5 volts. But if you just want a reasonable brightness for an indicator led, stick to 150 ohms (give or take 50 ohms) for normal brightness of virtually any led.
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Quick question as well. I want to add a multi color led. Red for on, and blue for vape. What I've found though is either no indication of what color will be what, or that when both positives are "on" it will be red. Is there a way to wire it the way I want or am I stuck with blue as on, and red as vape?
If you have a bicolor LED it probably has 3 leads on it. One long lead which is normally the negative terminal (-) and two shorter leads, one for each of the two colors and are the positive terminals (+).
The longer lead is wired to the negative part of your circuit. Then you can apply a positive lead with resistor to each of the two smaller leads separately and use whichever one you want for whatever purpose. It's just like two leds in one but each sharing a common ground.
Hope this helps.
The longer lead is wired to the negative part of your circuit. Then you can apply a positive lead with resistor to each of the two smaller leads separately and use whichever one you want for whatever purpose. It's just like two leds in one but each sharing a common ground.
Hope this helps.
If you stick to 100 ohms for 3.7v and 470 ohms for 5v you will be okay with most LEDs. That's what I have been using and works well for me. I use 470 for 5 volts to dim down the brightness a bit because anything less is usually too bright.
You can just tack solder your resistor to the led and try it with the batteries to see how your particular led behaves and make sure you have the correct brightness you want.
I have a protoboard that I use to test various values which makes it pretty easy. Plug and play.
You can just tack solder your resistor to the led and try it with the batteries to see how your particular led behaves and make sure you have the correct brightness you want.
I have a protoboard that I use to test various values which makes it pretty easy. Plug and play.
I understand what your saying, and I think I understand how to wire it all up. I guess what's throwing me is the dual color led at madvapes. It states that if both positives are on, I.e. Kill switch on, and vape switch depressed, then a certain color will automaticly be on. My understanding is that if say blue gets a positive feed it will be on, if red gets a positive feed it will be on, and if both get a positive feed red will be on. Is this correct thinking?If you have a bicolor LED it probably has 3 leads on it. One long lead which is normally the negative terminal (-) and two shorter leads, one for each of the two colors and are the positive terminals (+).
The longer lead is wired to the negative part of your circuit. Then you can apply a positive lead with resistor to each of the two smaller leads separately and use whichever one you want for whatever purpose. It's just like two leds in one but each sharing a common ground.
Hope this helps.
Sorry, I misread your original question. I just spent some time trying to find an answer for you but all I could find was that what is called the "dominant wavelength" for that particular LED is red, and you would need one that is blue.
If I can find an answer I'll let you know.
If I can find an answer I'll let you know.
That's exactly what I thought. How can you find the dominant wave length. Most other dual color LEDs don't specify what color will be the dominant color. Is inalways going to be red in a blue/red led? Guess more reseach is needed. Thanks for your help thus far.
I'm actually not 100% sure about the dominate wavelength yet, but my thoughts are now looking at the use of a tri-color LED, the RGB (Red Green Blue). Depending on how their leads are wired, you can get any one of those colors to light and if done properly, pretty much anywhere along the color spectrum.
I'll post as I learn.
I'll post as I learn.
Thanks for all the help. I wonder if the dual color ones have something in it that tells it when the two positives are on and defaults the Ed to be on a d blue off, or If the red just overpowers the blue. If that was the case you think it would end up with a mauve or purple look to it. Just thinking out loud here. I'm not very knowledgeable on the subject.
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