Bead LED (R8) Circuit

I am designing a small PCB board that consists of Vertical Header Pins for VCC(3.3V DC) and GND.
The input is supplied to the 3 Bead LEDs in parallel. I have made an initial schematic (https://drive.google.com/file/d/0B8h1l1g7x3y8YVBnYWdGMnM1VVU/view?usp=sharing).
I need review help on the Schematic and help in generating the fill area for my PCB.
Rest i’m aware of and would revert if more help is needed.

Thanks in advance!

Connecting LED’s (or any diodes) in parallel is usually disappointing because they seldom share current equally.

Will there be an external circuit connected to J1 that controls LED current?

Dale

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If you really need to connect LED in parallel add a small resistor (1R or less) in series for each diode. Becuse each LED are different parameters (even in single batch), these resistors add a small amount of voltage drop to equalize currents.

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Assuming that by “bead leds” @kggp1995 actually means the white leds commonly used in LED car lights, these do have Vf of about 3V and are often wired in direct parallel.

Thanks for all your reply, here’s the datasheet of the LED http://www.farnell.com/datasheets/1636581.pdf

Yes, sure. Does the 1Ohm 1/4 W resistor fit this case?
Also, the LEDs may scale upto 4 in parallel instead of the just 3 LEDs…

LED controlled from the output of a simple transistor that switches the ON/OFF state

Looking at the datasheet, the V4 and V5 ranks won’t work well on a 3V3 supply.
Also you want a mosfet switch. A biploar transistor saturation voltage will be too high

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