Hello!
I'm trying to make calculations for a 900 led matrix (the 5mm white transparent & bright ones) that I want to use it for videography ligths, as a DIY proyect.
I'm a beginner on electronics, but after read the basics I can make simple circuits with leds (I'm already make a few ones but only 7 led max.).
Data:
Power suply: 12v
Led: 3,7v, 20ma
My first thought was make a simple paralel conection: 30 treads of 30 leds each one. but, after calculations I had this results:
-A resistor of 15ohm for each thread, with 5w consumption
- 2,2w of consumption for each thread for leds
so... 5w+2,2w=7,2w x 30 threads, 216w. To move all this circuit need a 18amp power supply (20ma X 900led= 18amp).
Then I think: Must be a more efficient way to connect all leds, in fact, commercial lamps made it of leds can work whit batteries (that is a VERY desirable feature that I would like make in this project)!
I array them in series-paralel in that way: 10 treads of 30 subseries of 3 leds each one, the resistor is for each thread.
Make calculations:
-A resistor of 45ohm for each thread , but only dispate 0,54w.
-A led consumption of 6,6w for thread
So.. 0,54w+6,6w=71,1w. But this array only needs 20ma X 300 (groups of 3 led in series)= 6amp power suply
Any error on my calculations?
Any advice, improve?
I'm trying to make calculations for a 900 led matrix (the 5mm white transparent & bright ones) that I want to use it for videography ligths, as a DIY proyect.
I'm a beginner on electronics, but after read the basics I can make simple circuits with leds (I'm already make a few ones but only 7 led max.).
Data:
Power suply: 12v
Led: 3,7v, 20ma
My first thought was make a simple paralel conection: 30 treads of 30 leds each one. but, after calculations I had this results:
-A resistor of 15ohm for each thread, with 5w consumption
- 2,2w of consumption for each thread for leds
so... 5w+2,2w=7,2w x 30 threads, 216w. To move all this circuit need a 18amp power supply (20ma X 900led= 18amp).
Then I think: Must be a more efficient way to connect all leds, in fact, commercial lamps made it of leds can work whit batteries (that is a VERY desirable feature that I would like make in this project)!
I array them in series-paralel in that way: 10 treads of 30 subseries of 3 leds each one, the resistor is for each thread.
Make calculations:
-A resistor of 45ohm for each thread , but only dispate 0,54w.
-A led consumption of 6,6w for thread
So.. 0,54w+6,6w=71,1w. But this array only needs 20ma X 300 (groups of 3 led in series)= 6amp power suply
Any error on my calculations?
Any advice, improve?