so your saying every 3 leds put a resistor?The LEDs would most likely be wired in strings of three, with a current limiter; either an active semiconductor device, or more likely a simple resistor.
60/3 = 20 strings
400mA / 20 = 20mA, which is a typical LED current.
Blue LEDs typically have a Vf of between 3.2v to 3.8v.
3.4v x 3 = 10.2v total.
So, the resistor would have to drop 1.8v across itself allowing 20mA to pass.
1.8v/20mA = 90 Ohms.
If each led needs 20mA to work then you can put up to 1000 leds! However, if you use Sgt's idea you can put up to 3000 leds with the same power consumption. Its a compromise between with what I mentioned before.I think ill go with a resistor every LED. How many do you think i can put on with a 12v dc car battery?
|Thread starter||Similar threads||Forum||Replies||Date|
|S||Novice needing help with soldering LED strip lights.||General Electronics Chat||10|
|Help about potentiometer||General Electronics Chat||13|
|Unknown diode. Need help||Technical Repair||3|
|B||Resistor identification help.||Technical Repair||15|
|I||Help finding an old part||Datasheets, Manuals & Parts Identification||3|
by Gary Elinoff
by Robert Keim
by Lisa Boneta
by Sam Holland