How to Use MDD20A CYTRON MOTOR DRIVER: Examples, Pinouts, and Specs

The MDD20A is a dual-channel motor driver designed for controlling DC motors and stepper motors. It is capable of handling up to 20A of continuous current per channel, making it ideal for high-power motor control applications. The driver features built-in protection mechanisms, including overcurrent and thermal overload protection, ensuring reliable operation even under demanding conditions. Its compact design and ease of use make it a popular choice for robotics, automation, and other motor control projects.

• Robotics (e.g., controlling robot wheels or arms)
• Automation systems
• Electric vehicles and carts
• Conveyor belts
• Stepper motor control for CNC machines or 3D printers

• Input Voltage Range: 7V to 30V DC
• Continuous Current: 20A per channel
• Peak Current: 30A per channel (for short durations)
• Control Signals: PWM (Pulse Width Modulation) and Direction
• PWM Frequency: Up to 20kHz
• Logic Voltage: 3.3V or 5V compatible
• Protection Features: Overcurrent, thermal shutdown, and undervoltage lockout
• Dimensions: 84mm x 62mm x 25mm
• Weight: Approximately 100g

The MDD20A has two sets of input pins for motor control and two sets of output terminals for connecting motors. Below is the pin configuration:

1. Power Supply: Connect a DC power supply (7V to 30V) to the VM and GND terminals. Ensure the power supply can provide sufficient current for your motors.
2. Motor Connections: Connect the motors to the output terminals (M1A, M1B, M2A, M2B). For DC motors, the polarity determines the default rotation direction.
3. Logic Connections: Connect the control signals (PWM1, DIR1, PWM2, DIR2) to a microcontroller or other control device. Ensure the logic voltage matches the microcontroller's output (3.3V or 5V).
4. Grounding: Connect the GND pin of the MDD20A to the ground of your microcontroller to ensure a common reference.

• Use appropriate heat dissipation methods (e.g., heatsinks or fans) if operating near the maximum current rating.
• Ensure the power supply voltage does not exceed 30V to avoid damaging the driver.
• Use a fuse or circuit breaker to protect the motor driver and connected components from overcurrent conditions.
• For stepper motors, use both channels of the MDD20A to control the two motor coils.

Below is an example of how to control a single DC motor using the MDD20A and an Arduino UNO:

// Define control pins for Motor 1
const int pwmPin = 9;  // PWM signal for speed control
const int dirPin = 8;  // Direction control

void setup() {
  // Set pin modes
  pinMode(pwmPin, OUTPUT);
  pinMode(dirPin, OUTPUT);
}

void loop() {
  // Rotate motor in one direction
  digitalWrite(dirPin, HIGH);  // Set direction
  analogWrite(pwmPin, 128);    // Set speed (0-255, 128 = 50% duty cycle)
  delay(2000);                 // Run for 2 seconds

  // Stop motor
  analogWrite(pwmPin, 0);      // Set speed to 0
  delay(1000);                 // Wait for 1 second

  // Rotate motor in the opposite direction
  digitalWrite(dirPin, LOW);   // Change direction
  analogWrite(pwmPin, 200);    // Set speed (200 = ~78% duty cycle)
  delay(2000);                 // Run for 2 seconds

  // Stop motor
  analogWrite(pwmPin, 0);      // Set speed to 0
  delay(1000);                 // Wait for 1 second
}

• Adjust the pwmPin and dirPin values to match your wiring.
• The analogWrite function sets the motor speed, where 0 is off and 255 is full speed.

1. Motor Not Spinning

   • Cause: Incorrect wiring or insufficient power supply.
   • Solution: Double-check all connections and ensure the power supply meets the voltage and current requirements.

2. Overheating

   • Cause: Operating near or above the maximum current rating without proper cooling.
   • Solution: Add a heatsink or fan to the motor driver and reduce the motor load if possible.

3. Erratic Motor Behavior

   • Cause: Noise or interference in the control signals.
   • Solution: Use shielded cables for control signals and ensure proper grounding.

4. Driver Not Responding

   • Cause: Logic voltage mismatch or damaged components.
   • Solution: Verify the logic voltage (3.3V or 5V) and inspect the driver for physical damage.

1. Can the MDD20A control stepper motors?

   • Yes, the MDD20A can control stepper motors by using both channels to drive the two motor coils.

2. What is the maximum PWM frequency supported?

   • The MDD20A supports PWM frequencies up to 20kHz.

3. Can I use the MDD20A with a 3.3V microcontroller?

   • Yes, the MDD20A is compatible with both 3.3V and 5V logic levels.

4. Is reverse polarity protection included?

   • No, the MDD20A does not have reverse polarity protection. Ensure correct power supply polarity to avoid damage.