How to Use A5984 Stepper Motor Driver Carrier: Examples, Pinouts, and Specs

The A5984 Stepper Motor Driver Carrier by Pololu (Manufacturer Part ID: 1194453) is a compact and efficient driver designed to control bipolar stepper motors. It offers advanced features such as adjustable current control, microstepping capabilities (up to 1/32-step), and built-in protection mechanisms like overcurrent and thermal shutdown. This makes it an excellent choice for applications requiring precise motor control, such as robotics, 3D printers, CNC machines, and other automation systems.

• Robotics and mechatronics
• 3D printers and CNC machines
• Automated conveyor systems
• Camera gimbals and pan-tilt systems
• Precision positioning systems

The A5984 Stepper Motor Driver Carrier has 16 pins. Below is the pinout and description:

1. Power Connections:

   • Connect the motor power supply (8 V to 35 V) to the VMOT pin.
   • Connect the logic power supply (3.3 V or 5 V) to the VDD pin.
   • Ensure all grounds (GND) are connected.

2. Motor Connections:

   • Connect the two coils of the stepper motor to OUT1A, OUT1B, OUT2A, and OUT2B.
   • Identify the motor coils using a multimeter if necessary.

3. Control Signals:

   • Use the STEP pin to send pulses for stepping the motor.
   • Use the DIR pin to set the rotation direction.
   • Configure the microstepping mode using the MS1 and MS2 pins.

4. Current Limiting:

   • Adjust the current limit by setting the REF voltage. Use the formula:

     Current Limit (A) = VREF / (8 × RS)
     

     where RS is the sense resistor value (typically 0.1 Ω).

5. Enable and Sleep:

   • Pull the ENABLE pin low to activate the driver.
   • Pull the SLEEP pin low to minimize power consumption when the driver is idle.

Below is an example of how to control the A5984 Stepper Motor Driver Carrier with an Arduino UNO:

// Define pin connections
#define STEP_PIN 3  // Connect to STEP pin on A5984
#define DIR_PIN 4   // Connect to DIR pin on A5984
#define ENABLE_PIN 5 // Connect to ENABLE pin on A5984

void setup() {
  // Set pin modes
  pinMode(STEP_PIN, OUTPUT);
  pinMode(DIR_PIN, OUTPUT);
  pinMode(ENABLE_PIN, OUTPUT);

  // Enable the driver
  digitalWrite(ENABLE_PIN, LOW); // Pull ENABLE low to activate driver
}

void loop() {
  // Set direction
  digitalWrite(DIR_PIN, HIGH); // Set direction to clockwise

  // Step the motor
  for (int i = 0; i < 200; i++) { // 200 steps for one revolution (1.8°/step motor)
    digitalWrite(STEP_PIN, HIGH); // Generate a step pulse
    delayMicroseconds(1000);      // 1 ms pulse width
    digitalWrite(STEP_PIN, LOW);
    delayMicroseconds(1000);      // 1 ms delay between steps
  }

  delay(1000); // Wait 1 second before reversing direction

  // Reverse direction
  digitalWrite(DIR_PIN, LOW); // Set direction to counterclockwise

  // Step the motor in reverse
  for (int i = 0; i < 200; i++) {
    digitalWrite(STEP_PIN, HIGH);
    delayMicroseconds(1000);
    digitalWrite(STEP_PIN, LOW);
    delayMicroseconds(1000);
  }

  delay(1000); // Wait 1 second before repeating
}

• Always use a decoupling capacitor (e.g., 100 µF) near the VMOT pin to stabilize the motor power supply.
• Ensure proper heat dissipation if operating near the maximum current limit.
• Avoid connecting or disconnecting the motor while the driver is powered to prevent damage.

1. Motor Not Moving:

   • Verify power supply connections to VMOT and VDD.
   • Check the ENABLE pin is pulled low to activate the driver.
   • Ensure the STEP pin is receiving pulses.

2. Motor Vibrates but Does Not Rotate:

   • Check the wiring of the motor coils. Ensure each coil is connected to the correct output pins.
   • Verify the DIR pin is set correctly for the desired direction.

3. Driver Overheating:

   • Reduce the current limit by adjusting the REF voltage.
   • Add a heatsink or improve ventilation around the driver.

4. FAULT Pin is Low:

   • Check for overcurrent or thermal shutdown conditions.
   • Ensure the motor is not drawing more current than the driver can handle.

• Can I use the A5984 with a unipolar stepper motor? No, the A5984 is designed for bipolar stepper motors only.

• What happens if I exceed the maximum input voltage? Exceeding 35 V on the VMOT pin can permanently damage the driver. Use a regulated power supply.

• How do I select a microstepping mode? Set the MS1 and MS2 pins according to the microstepping mode table provided in the technical specifications.

This concludes the documentation for the A5984 Stepper Motor Driver Carrier. For further assistance, refer to the Pololu product page or contact technical support.