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I have 3 led's, would the diagram work the way i want,? Answered

 i would like the 3 leds to work as follows, left speaker left led, right speaker right led, and central led will be off of both speakers, i am quite sorry for my ignorance, i am very new to this and it is a gift for a friend, so i really want to know as much as i can before  i start blowing things up :), 

each led is 1 watt and works best at 700 ma from what i understand, but can work between 350-700, so i am hoping 600 ma is fine, i have a wall plug adapter with switch for 3-12v, i will be using a v meter to test these numbers are accurate, it says current 600 ma., in my previous posts i was recommended to buy a CCR, but i haven't the  time to order this,  will this power source eliminate the need? i also have picked up quality heat sinks, and arctic silver, i am not the best at electronics, i do have a relative who works with HVolt  batterys and knows some about electronics, he works at TDI in nj, hes busy so cant ask him much, i am hoping this to be my last post, please help a guy out, thank you all for your support and positive and helpful comments

first image without resistors second with



7 years ago

No, this will not work. The power supply is too small. The transistors are not connected properly.

Use one of your original drawings from your other post; one of them will work (the second, I think?) I realize you want your colours to mix and stuff but this is not the way to go about it.

(agreeing with steve') you'll need more than 1A and up to 2.1A power supply if you rig them up like that.


ok i have a different power supply, specs are :
Switching Power Supply
Input 100-240v~50/60hz 600 ma
output 15v DC 1500ma

with this PS, should it be ok? and what resistors should i now be using
Thank you :)

You MUST have current limiting resistors or other current limit measures, and you really need a 1K resistor to each base terminal.

Please don't clutter answers with more questions on the same topic- just reply to your original post.


i did math i will need a 1 watt 1 ohm resistor on each for this set up i think

Its not good to have the LEDs running on low value resistors like that, because they won't light up fully, and they aren't that stable with temperature. As Lemonie says, you can't GET 4 x 600mA from a 600mA PSU. Its like having a faucet that delivers 1 gallon per minute when its fully on. Even if you put it in little buckets, it still adds up to 1 gallon per minute !

Well the smoke curling up in what light was left would be kinda psychedelic for a bit.