I need some help choosing a transistor for my project

Hi, my name is Fabrizio, I’m just starting with arduino and i want to make a LED strip (5050 - 5 meters) to play along with music. I have this schema and the code, but i want to know why is this guy using IRF520 Mosfet to power the leds, i mean, why that mosfet and not other? It will be really helpful it someone could explain me a little more about the best option for a transistor/mosfet to use in this case.
Thanks in advance!

Scematics-on-beat-RGB-strip.jpg

5 meters is a lot of LEDs, which will require a lot of current. You need a beefy transistor to handle a lot of current without excessive heating which is inefficient and could damage the transistor.

@tylernt: Yes, the LEDs work with 6A. So the IRF520 is a good choice, or you'd recommend something else?

When looking for MOSFETs for direct drive from logic level (5V) signals, you must get logic-level MOSFETs.

the key spec on the datasheet is the value of Vgs at which the Rds(on) is specified. "Rds(on) at Vgs=4.5V" is typically the specification to look for. 4.5V is used to allow for below-spec 5V supplies. If the only Rds(on) values are given for Vgs=10V, or if Vth is specified as "2--4V" then is NOT logic level.

Vth (threshold voltage) confuses a lot of newcomers - its the voltage at which the device switches OFF. For logic level devices it will typically be 0.5 to 1.0V or so.

Try FQP30N06L, FDP65N06, IRLU3636PBF, or FDP3651U

You might look at the below logic level MOSFET and board.

https://www.sparkfun.com/products/10213

https://www.sparkfun.com/products/12959

frcavada: @tylernt: Yes, the LEDs work with 6A. So the IRF520 is a good choice, or you'd recommend something else?

As others already have told you, this fet is NOT a good choice for this application. You need a LOGIC fet. They sometimes have an "L" in the serial number.

A 220ohm gate resistor, as on the schematic diagram, is good. Adding a three 10k resistors, from each output pin to ground, is wise. That keeps the gate firmly grounded when Arduino boots up. Leo..

Thanks to all, as you're saying this one "IRL520NPbF" should work, right?

@BillHo , for those that you proposed

BillHo: Try FQP30N06L, FDP65N06, IRLU3636PBF, or FDP3651U

, the only one that i can get in my country is the FDP3651U, but i read the datasheet and it only says Rds(on) values for Vgs=10V, and you said that it'd not be a logical one for this reason. Does it work anyway?

Thanks again

IRF520 is a high voltage fet. NOT ok for 12volt. 0.22ohm @5voltGS is quite high. You will loose 1.32volt. Less brightness when all LEDs are on, and 8watt of heat in the mosfet (heatsink NEEDED). Better find another one.

FDP3651U is also a high voltage fet, and NOT a logic fet. Not suitable.

https://www.sparkfun.com/products/10213 0.035ohm @5voltGS. 0.21volt loss@6A. 1.26watt of heat@6A. Probably no heatsink needed.

State your country. Maybe be we can find you a supplier. Leo..

Wawa: IRF520 is a high voltage fet. NOT ok for 12volt. 0.22ohm @5voltGS is quite high. You will loose 1.32volt. Less brightness when all LEDs are on, and 8watt of heat in the mosfet (heatsink NEEDED). Better find another one.

FDP3651U is also a high voltage fet, and NOT a logic fet. Leo..

Ok, thanks a lot, what about this one? IRLZ24N

I’m from Chile, this is a list of the components of my best supplier so far.
Link

BUK9508-55b is a logic fet. 0.008ohm

FDP8880 is a logic fet. 0.012ohm

Rest is not suitable

Wawa: BUK9508-55b is a logic fet. 0.008ohm

FDP8880 is a logic fet. 0.012ohm

Rest is not suitable

Thanks a lot!