Controlling High Current Output with Arduino: Utilizing MOSFET for Switching

Arduino boards are capable of controlling a wide range of electronic components, but their direct output is typically limited to around 40mA per pin. However, there are instances where it becomes necessary to switch higher current loads. To overcome this limitation, MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) or transistors can be employed to act as switches and handle higher currents. This article will guide you through an example that demonstrates the use of a MOSFET to control high current output with Arduino.

Understanding MOSFET for High Current Output

A MOSFET is a type of transistor that is commonly used to switch high current loads in electronic circuits. By connecting the gate pin of the MOSFET to an Arduino pin, we can control the flow of current through the load connected to the drain pin. This allows us to switch on and off higher current devices, such as motors or other non-inductive loads, using an Arduino board.

Circuit Diagram

Note: When working with high current loads, it is important to consider proper circuit design and protection. The provided schematic in this example showcases the use of a motor with a protection diode. However, other non-inductive loads can be utilized without the need for a diode. Ensure that the components and circuit design are suitable for your specific application to prevent damage or unexpected behavior.

PIN connected arduino pin number 5

Example Code

The following code snippet provides an example of using a MOSFET to switch a high current load on and off five times every second:

int outPin = 5; // Output pin for the MOSFET

void setup() {
  pinMode(outPin, OUTPUT); // Sets pin 5 as an output
}

void loop() {
  for (int i = 0; i <= 5; i++) { // Loops 5 times
    digitalWrite(outPin, HIGH); // Turns the MOSFET on
    delay(250); // Pauses for 1/4 second
    digitalWrite(outPin, LOW); // Turns the MOSFET off
    delay(250); // Pauses for 1/4 second
  }

  delay(1000); // Pauses for 1 second
}

Conclusion

Controlling high current output from an Arduino board requires the use of MOSFETs or transistors as switches. By employing these components, you can effectively handle loads that exceed the Arduino’s direct output capabilities. This article introduced the concept of using MOSFETs for high current output control and provided an example code snippet for quick switching. When working with high current loads, always consider circuit design and proper protection to ensure safe and reliable operation