Driving multiple 24V leds with MOSFETs

Hello, I have these buttons that have 24V leds. LAS3F-11/24/Y ONPOW - Switch: push-button | Pos: 2; SPDT; 0.5A/250VAC; 1A/24VDC; ON-(ON); V10F-11-24Y | TME - Electronic components

Im working on a project where I'd need to drive 10 of those leds separately with an Arduino mega. MOSFET seems to be the way to go, but I'm not really familiar with them.

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This seems to be the way to connect the mosfet, but I'm a bit lost on how to calculate the resistor size and I'm also looking for recommendations for what would be a great MOSFET and power supply to use.

MOSFET is usually used for heavy loads but can also be used for LEDs. I do not find how much current should work on this LEDs but I guess transistor 2N7000 will work - it can withstand up to 60V and current up to 200mA. The value of the resistor is not critical and in this case it depends on how much current the microcontroller can provide at the output - probably any from 1k to 10k will work. Because you will control 10 LEDs instead of using 10 pins of Arduino you can add 2 pieces of 74HC595 and with 3-4 pins from Arduino to control up to 16 LEDs (or more by just increasing the number of 74HC595 and the transistors of course).

For a power supply, you might use a boost DC to DC converter like the MT3608 - from 5V power source for the Arduino you will get 24V for LEDs.

Good luck.

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Tpic6b595 is an 8-bit shift register, very similar to 74hc595, but with built-in MOSFETs. You would need 2, but it could save you quite a lot of wiring/soldering.

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