Most of us love to decorate things around us to make it look better. In fact attractive environment can set and enlighten the mood to a great extent. Adapting this idea and using this design you can perform your desktop decoration in workplace, home etc using LED’s. And the best thing about the design is it is powered by System USB port no power special power supply arrangement required.
This decorative lights was powered by system USB port which gives 5V/500mA as output. This design was intend to lit up the speakers placed near the your PC. The LED section was categorized into two groups one for the Left speaker and another for the right. Each groups contains 2-Red, 2-green and 2- Blue LED’s for decoration. The calculation is as follows
Red and Green LED’s operate at 2v/20mA. Since Red and Green LED’s are connected in series current consumption remains same. So the current limiting resistor
R1 = ( Vcc- LED voltage ) / Current
R1 = ( 5 – 4 )/ 20mA
R1= 50 Ohm.
Blue LED’s operate at 3v/30mA. So the current limiting resistor is
R2 = ( Vcc – LED voltage ) / Current
R2 = ( 5 – 3 ) / 30mA
R2 = 60 ohm.
The total current consumption by a single group that is Red, blue and green LED’s two each is given by
Itotal = 2 x ( 20 + 30 ) mA
Itotal = 100mA.
Each group takes 100mA making the total current consumption to 200mA. You can add, replace combine LED’s but make sure it takes only upto 500mA. I hope the idea was clear so now you have to figure out how to build and where to place the LED’s around your desktop. Think of creative combinations and make your Desktop environment attractive. Here are some ideas for you.
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