Optimal method for multiple MOSFETs for LED driving with a shared power rail

Question

I have three LEDs (RGB), with the following forward voltages and current:

• red 2.25 V @ 0.35 A
• green 3.3 V @ 0.35 A
• blue 3.1V @ 0.35 A

I plan on using three (3) RFP30N06LE MOSFETs in parallel @ 0.35 A each using independent TTL-based PWM dimming from the PWM pins of an Arduino, each MOSFET connected in parallel to a shared 9V - 12V @ 1 A power rail fed with a wall wart supply.

What would the optimal method be to wire these MOSFETs in parallel and use the same shared power rail?

Answer 1

Just like that, in parallel:

^{simulate this circuit – Schematic created using CircuitLab}

However, if all three LEDs can be on at once, you might want a bigger power supply. The maximum current to power the LEDs is:

$$ 0.35A + 0.35A + 0.35A = 1.05A $$

This is 5% more than your power supply's rating already, plus you need to allow for some current to power control circuitry probably, and probably you want to allow some margin for reliable operation.