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LED & electronics newbie project Answered

Im brand spanking new to electronics so i have a few questions here on LEDs. If you connect say 20 LEDs in series, can you still power them with regular batteries (1.5V)? I would like to use the mains to power the LEDs. I have various adapters lying around ranging grom 5V to 12V. What changes, if any, will I have to make to the configuration and will I need extra components? I want to make lighting for a very small permanently dark room where I can use a switch to turn on the LED lights.


You won't want to hook them all up in series. At a minimum you'll need a 40V power source. You'd be better off running them in parallel or at least series-parallel. metku.net had my favorite LED resistor calculator, but they seem to be down.

Thanks im checking the resistance calcs and will try and understand them. How do i connect them in parallel? Will the LEDs dim? This is the configuration i have at the moment with 20 LEDs (not tested yet). Does it look safe enough?


Search the internet for LED resistor calculator. There seem to be a lot of copies of the same calculator that only takes input valtage of 32V, but it would be a good start for you.