Hello everyone,
I am a woodworker specializing in display stands. I have been installing LED's in my displays for some time now and continually run into the same issue - I frequently get requests for a setup of Red, Yellow, and Green LEDs in a particular display (see pic). The problem is that these lights have different forward voltages, and the greens always end up significantly brighter than the yellow and red. Here are the specs for the LEDs:
Green: 3.0 - 3.4v 20mA - 12000 mcd
Yellow: 1.8 - 2.2v 24mA - 12000 mcd
Red: 1.8 - 2.2v 24mA - 12000 mcd
Supply Voltage: 9v
I have tried wiring them both totally in series, which does not light whatsoever, and in parallel, in which case the brightness is the issue. I have seen pairs of LEDs in series then wired in parallel but i'm totally confused about that one. I have tried multiple different resistors suggested by online calculators, in every location of the circuit I can think to try. But nothing seems to even out the brightness. I have very little knowledge of electronic circuits so I'm hoping someone will be kind enough to propose a solution, because I'm just stabbing in the dark at this point. I've attached a diagram of how the LEDs are laid out, if any further information is needed please let me know. Thanks for your time and help in advance!
I am a woodworker specializing in display stands. I have been installing LED's in my displays for some time now and continually run into the same issue - I frequently get requests for a setup of Red, Yellow, and Green LEDs in a particular display (see pic). The problem is that these lights have different forward voltages, and the greens always end up significantly brighter than the yellow and red. Here are the specs for the LEDs:
Green: 3.0 - 3.4v 20mA - 12000 mcd
Yellow: 1.8 - 2.2v 24mA - 12000 mcd
Red: 1.8 - 2.2v 24mA - 12000 mcd
Supply Voltage: 9v
I have tried wiring them both totally in series, which does not light whatsoever, and in parallel, in which case the brightness is the issue. I have seen pairs of LEDs in series then wired in parallel but i'm totally confused about that one. I have tried multiple different resistors suggested by online calculators, in every location of the circuit I can think to try. But nothing seems to even out the brightness. I have very little knowledge of electronic circuits so I'm hoping someone will be kind enough to propose a solution, because I'm just stabbing in the dark at this point. I've attached a diagram of how the LEDs are laid out, if any further information is needed please let me know. Thanks for your time and help in advance!
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