N-Channel MOSFET for switching 400mA @ 3.3V

[Tantal]

I am looking for a logic level N-Channel MOSFET for switching 400mA @ 3.3V (I'd like to turn on/off LEDs with a 3.3V Arduino).

R_DS,on and V_GS(th) seem to be the key parameters here, no?

Which one would you recommend?

[con-f-use]

1. Go to mouser or the distributor of your choice
2. Look for N-MOS, filter for >500 mA, a threshold voltage <2V and maybe the package (smd, through-hole)
3. Order 100 of the cheapest

The majority of N-MOS on the planet should suit your needs. A typical jelly-bean is the NTR4170.

(Bonus Points: Calculate on-state power and compare it to the datasheet's thermal characterisitcs, most should take your 400mA without hesitation, unless you plan to switch really rapidly)