My son is working on a project in which he is using 36 total LEDs consisting of 7 different LED's. There are 6 different solid colored LEDs varying from 1.88v to 3.2v and one color changing that is around 3v - 3.5v. He is wiring the LEDs in series of 3 and wants to connect 4 series, for a total of 12 LEDs to one 9 volt battery which will be wired to a lighted switch. Ideally, I would like to experiment with him to find the best solutions, but we are on limited time, so I am hoping to get a few answers to help him along. I'm a novice with this stuff, so please let me know if I need to add any additional information.
Here is a rough overview of the layout for 4 of the series that have the biggest difference in voltage. There would be 2 other sets similar to this, but the voltages of the LED's would be closer to each other.
My questions are this.
The switch is a lighted toggle switch (I believe it's 12v). I know that it can be powered by a 9v as we have used it in other projects, but not like this. Will the power drain from the switch impact the LED's? If so, can multiple 9v batteries be wired into the switch in parallel and will that have any impact?
Will running different rated LED's in the same series have a negative impact? He is looking to put the lower voltage LED's in the front of the series. Will that hurt the higher voltage LED's that follow them? He is looking to wire 2 solid color LED's on the same series as one of the color changing LED's.
What can he expect as far as battery life with this setup? He only needs it to stay powered for 10 minutes max.
When running multiple series in parallel. Will he need a resistor on each series or is one resister between the end of all series and the power source sufficient?
Thanks for any help you can provide!