Excelcier
03-04-2003, 05:09 PM
Ok, there has been a large amount of posts where people have wanted to know the proper resistor values. Here's the final answer with electrical background and reasoning so people can stop asking.
OPEN THE ATTACHED PICTURE FOR THE CALCULATION!
Take a common blue LED for example from case-mod.com;
5mm Blue LED - 2200 MCD
Specs:
Emitting Color: Blue
Wavelength(nm): 470
Lens Type: Water Clear
Typ. MCD: 2200mcd
Typ. Voltage: 3.5v (4.0v MAX)
mA: 20
Viewing Angle: 15
Lead Length: 27mm
The important items is the max voltage and mA rating. Electrical theory 101;
V=IR voltage = current x resistance.
There, now quit asking....
OPEN THE ATTACHED PICTURE FOR THE CALCULATION!
Take a common blue LED for example from case-mod.com;
5mm Blue LED - 2200 MCD
Specs:
Emitting Color: Blue
Wavelength(nm): 470
Lens Type: Water Clear
Typ. MCD: 2200mcd
Typ. Voltage: 3.5v (4.0v MAX)
mA: 20
Viewing Angle: 15
Lead Length: 27mm
The important items is the max voltage and mA rating. Electrical theory 101;
V=IR voltage = current x resistance.
There, now quit asking....