How to Use VNH5019: Examples, Pinouts, and Specs

The VNH5019 is a high-current H-bridge motor driver designed to control DC motors in both forward and reverse directions. Manufactured with robust protection features such as overcurrent protection, thermal shutdown, and under-voltage lockout, the VNH5019 is ideal for applications requiring reliable motor control. Its compact design and high current-handling capability make it a popular choice for robotics, industrial automation, and remote-controlled vehicles.

• Robotics and automation systems
• Remote-controlled vehicles
• Conveyor belts and industrial actuators
• Electric wheelchairs and mobility devices
• General-purpose DC motor control

The VNH5019 motor driver is designed to handle high currents and voltages while providing precise motor control. Below are its key technical specifications:

The VNH5019 has 30 pins, with key pins used for motor control and power connections. Below is a summary of the most important pins:

1. Power Connections:

   • Connect the motor power supply to the VIN pin (5.5V to 24V).
   • Connect the logic power supply (3V to 5.5V) to the VCC pin.
   • Ensure all GND pins are connected to the ground of the power supply.

2. Motor Connections:

   • Connect the motor terminals to the OUTA and OUTB pins.

3. Control Signals:

   • Use the INA and INB pins to control the motor direction:
     • INA = High, INB = Low: Motor rotates forward.
     • INA = Low, INB = High: Motor rotates backward.
     • INA = Low, INB = Low: Motor brakes (low-side braking).
     • INA = High, INB = High: Motor brakes (high-side braking).
   • Use the PWM pin to control motor speed by providing a PWM signal (up to 20 kHz).

4. Enable and Diagnostics:

   • Pull the EN/DIAG pin high to enable the driver.
   • Monitor the EN/DIAG pin for fault conditions (e.g., overcurrent or thermal shutdown).

5. Current Sensing:

   • The CS pin outputs a voltage proportional to the motor current. Use this for monitoring or feedback.

• Use decoupling capacitors (e.g., 100 µF electrolytic and 0.1 µF ceramic) across the VIN and GND pins to reduce noise and voltage spikes.
• Ensure the motor's stall current does not exceed the VNH5019's peak current rating (30A).
• Use heat sinks or proper ventilation if operating near the maximum current limit to prevent thermal shutdown.
• Avoid reverse polarity on the VIN or VCC pins to prevent damage to the driver.

Below is an example of how to control a motor using the VNH5019 with an Arduino UNO:

// Define pin connections
#define INA 7       // Connect to INA pin of VNH5019
#define INB 8       // Connect to INB pin of VNH5019
#define PWM 9       // Connect to PWM pin of VNH5019
#define EN_DIAG 10  // Connect to EN/DIAG pin of VNH5019

void setup() {
  // Set pin modes
  pinMode(INA, OUTPUT);
  pinMode(INB, OUTPUT);
  pinMode(PWM, OUTPUT);
  pinMode(EN_DIAG, OUTPUT);

  // Enable the motor driver
  digitalWrite(EN_DIAG, HIGH);
}

void loop() {
  // Rotate motor forward at 50% speed
  digitalWrite(INA, HIGH);
  digitalWrite(INB, LOW);
  analogWrite(PWM, 128); // 50% duty cycle (128 out of 255)
  delay(2000);           // Run for 2 seconds

  // Rotate motor backward at 75% speed
  digitalWrite(INA, LOW);
  digitalWrite(INB, HIGH);
  analogWrite(PWM, 192); // 75% duty cycle (192 out of 255)
  delay(2000);           // Run for 2 seconds

  // Brake the motor
  digitalWrite(INA, LOW);
  digitalWrite(INB, LOW);
  analogWrite(PWM, 0);   // Stop PWM signal
  delay(2000);           // Brake for 2 seconds
}

1. Motor Does Not Spin:

   • Ensure the EN/DIAG pin is pulled high to enable the driver.
   • Verify that the INA, INB, and PWM signals are correctly configured.
   • Check the motor power supply voltage and connections.

2. Driver Overheats:

   • Ensure the motor's current does not exceed the VNH5019's maximum ratings.
   • Add a heat sink or improve ventilation around the driver.

3. Fault Detected on EN/DIAG Pin:

   • Check for overcurrent or thermal shutdown conditions.
   • Reduce the motor load or improve cooling.

4. No Current Sense Output:

   • Verify the CS pin connection and ensure it is not left floating.
   • Check the motor current; the CS pin only outputs a voltage proportional to the current.

Q: Can the VNH5019 drive two motors simultaneously?
A: No, the VNH5019 is a single H-bridge driver designed to control one motor at a time.

Q: What is the maximum PWM frequency supported?
A: The VNH5019 supports PWM frequencies up to 20 kHz.

Q: Is reverse polarity protection included?
A: No, the VNH5019 does not have built-in reverse polarity protection. Use external diodes or circuitry to prevent damage.

Q: Can I use the VNH5019 with a 3.3V microcontroller?
A: Yes, the VNH5019 is compatible with logic levels from 3V to 5.5V, making it suitable for 3.3V microcontrollers.