How to Use IRLZ34N: Examples, Pinouts, and Specs

The IRLZ34N is an N-channel MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) designed for high-speed switching applications. It is known for its low on-resistance (R_DS(on)), which ensures efficient power management and minimal energy loss. This component is widely used in circuits requiring high current handling and fast switching capabilities.

• Power supplies and voltage regulation
• Motor control and driver circuits
• LED lighting systems
• Battery management systems
• DC-DC converters
• General-purpose switching in high-current applications

Below are the key technical details of the IRLZ34N MOSFET:

The IRLZ34N is housed in a TO-220 package with three pins. The pinout is as follows:

1. Gate Control: Apply a voltage to the Gate (G) to control the MOSFET's switching state. A voltage of 5V or higher is typically sufficient to fully turn on the IRLZ34N.
2. Drain-Source Current Flow: When the Gate is activated, current flows from the Drain (D) to the Source (S). Ensure the current does not exceed the maximum rating of 30A.
3. Heat Dissipation: Use a heatsink with the TO-220 package to manage heat dissipation, especially in high-current applications.
4. Protection: Add a flyback diode across inductive loads (e.g., motors) to protect the MOSFET from voltage spikes.

The IRLZ34N can be used to control a DC motor with an Arduino UNO. Below is an example circuit and code:

• Gate (G): Connect to an Arduino digital pin (e.g., D9) through a 220Ω resistor.
• Drain (D): Connect to one terminal of the motor.
• Source (S): Connect to ground (GND).
• The other terminal of the motor connects to the positive supply voltage (e.g., 12V).
• Add a flyback diode (e.g., 1N4007) across the motor terminals to protect the MOSFET.

// Example code to control a DC motor using the IRLZ34N MOSFET
// The motor is connected to pin D9 of the Arduino UNO

const int motorPin = 9; // Define the pin connected to the MOSFET Gate

void setup() {
  pinMode(motorPin, OUTPUT); // Set the motor pin as an output
}

void loop() {
  analogWrite(motorPin, 128); // Set motor speed to 50% (PWM value: 128)
  delay(5000);               // Run motor for 5 seconds

  analogWrite(motorPin, 0);  // Turn off the motor
  delay(5000);               // Wait for 5 seconds
}

• Use a pull-down resistor (e.g., 10kΩ) on the Gate pin to ensure the MOSFET remains off when no signal is applied.
• Avoid exceeding the maximum voltage and current ratings to prevent damage.
• Ensure proper grounding and minimize noise in the circuit for reliable operation.

1. MOSFET Not Turning On

   • Ensure the Gate voltage is at least 5V for full activation.
   • Check for loose or incorrect connections in the circuit.

2. Excessive Heat

   • Verify that the current through the MOSFET does not exceed 30A.
   • Use a heatsink to dissipate heat effectively.

3. Motor Not Running

   • Check the flyback diode orientation and ensure it is properly connected.
   • Verify the PWM signal from the Arduino is functioning correctly.

4. MOSFET Damage

   • Ensure the Gate-Source voltage does not exceed ±16V.
   • Protect the MOSFET from voltage spikes using appropriate components (e.g., TVS diodes).

Q: Can the IRLZ34N be used with 3.3V logic?
A: The IRLZ34N is optimized for 5V logic levels. While it may partially turn on with 3.3V, it is recommended to use a logic-level MOSFET specifically designed for 3.3V operation.

Q: What is the purpose of the flyback diode?
A: The flyback diode protects the MOSFET from voltage spikes generated by inductive loads, such as motors or relays, during switching.

Q: Can I use the IRLZ34N for AC applications?
A: The IRLZ34N is primarily designed for DC applications. For AC applications, consider using a TRIAC or other suitable components.

Q: How do I calculate the required heatsink size?
A: Use the formula P = I² × R_DS(on) to calculate power dissipation, then select a heatsink with adequate thermal resistance to maintain safe operating temperatures.