How to Use DVR8825 Stepper Driver: Examples, Pinouts, and Specs

The DVR8825 is a high-performance microstepping driver designed for controlling stepper motors. It features adjustable current control, enabling smooth motor operation and reduced noise. With support for up to 2.5A per phase and multiple microstepping modes (full, half, quarter, eighth, and sixteenth), the DVR8825 is ideal for applications requiring precise motor control. Common use cases include robotics, 3D printers, CNC machines, and other automation systems.

• Input Voltage Range: 8.2V to 45V
• Maximum Current per Phase: 2.5A (with sufficient cooling)
• Microstepping Modes: Full, 1/2, 1/4, 1/8, 1/16
• Logic Voltage: 3.3V or 5V compatible
• Thermal Shutdown Protection: Yes
• Overcurrent Protection: Yes
• Dimensions: 15mm x 20mm (approx.)

The DVR8825 has 16 pins, which are typically arranged as follows:

The microstepping mode is determined by the states of the MS1, MS2, and MS3 pins:

1. Power Supply: Connect the motor power supply (8.2V to 45V) to the VMOT and GND pins. Add a decoupling capacitor (e.g., 100µF) across these pins to reduce voltage spikes.
2. Motor Connection: Connect the stepper motor coils to the A1, A2, B1, and B2 pins. Ensure the correct pairing of the motor wires.
3. Logic Power: Connect the VDD pin to the logic voltage (3.3V or 5V) and the GND pin to the logic ground.
4. Control Signals: Connect the STEP and DIR pins to your microcontroller or control circuit. Use the ENABLE pin to enable or disable the driver as needed.
5. Microstepping Configuration: Set the MS1, MS2, and MS3 pins to configure the desired microstepping mode.
6. Current Adjustment: Use the onboard potentiometer to adjust the current limit. Start with a low setting and gradually increase it while monitoring the motor's performance and temperature.

• Heat Dissipation: The DVR8825 can handle up to 2.5A per phase with adequate cooling. Use a heatsink or active cooling to prevent overheating.
• Current Limiting: Set the current limit to match your stepper motor's rated current to avoid damaging the motor or driver.
• Decoupling Capacitors: Always use a capacitor (e.g., 100µF) across the VMOT and GND pins to protect the driver from voltage spikes.
• Sleep Mode: Use the SLEEP pin to reduce power consumption when the driver is not in use.
• Fault Handling: Monitor the FAULT pin to detect and respond to fault conditions.

Below is an example of how to control a stepper motor using the DVR8825 and an Arduino UNO:

// Define pin connections
#define STEP_PIN 3  // Connect to the STEP pin of the DVR8825
#define DIR_PIN 4   // Connect to the DIR pin of the DVR8825

void setup() {
  pinMode(STEP_PIN, OUTPUT); // Set STEP pin as output
  pinMode(DIR_PIN, OUTPUT);  // Set DIR pin as output

  digitalWrite(DIR_PIN, HIGH); // Set initial direction (HIGH = one direction)
}

void loop() {
  // Generate a step pulse
  digitalWrite(STEP_PIN, HIGH); // Set STEP pin HIGH
  delayMicroseconds(500);       // Wait for 500 microseconds
  digitalWrite(STEP_PIN, LOW);  // Set STEP pin LOW
  delayMicroseconds(500);       // Wait for 500 microseconds
}

1. Motor Not Moving:

   • Check the power supply connections to VMOT and GND.
   • Verify the STEP and DIR signals from the microcontroller.
   • Ensure the motor coils are correctly connected to A1, A2, B1, and B2.

2. Overheating:

   • Ensure the current limit is set correctly using the potentiometer.
   • Add a heatsink or active cooling to the driver.

3. Driver Not Enabling:

   • Check the ENABLE pin. It should be pulled low to enable the driver.
   • Verify the logic power supply (VDD and GND).

4. Fault Condition (FAULT Pin Low):

   • Check for overcurrent or thermal shutdown conditions.
   • Reduce the current limit or improve cooling.

5. Motor Vibrating but Not Rotating:

   • Verify the microstepping mode configuration (MS1, MS2, MS3).
   • Ensure the motor coils are correctly paired.

• Can I use the DVR8825 with a 12V power supply? Yes, the DVR8825 supports motor power supplies from 8.2V to 45V, so 12V is within the acceptable range.

• How do I set the current limit? Use the onboard potentiometer. Measure the VREF voltage and calculate the current limit using the formula:
  Current Limit = VREF × 2 (for DVR8825).

• What happens if I exceed the current limit? The driver will enter overcurrent protection mode, and the FAULT pin will go low. Reduce the current limit or improve cooling to resolve this.

• Can I use the DVR8825 with a 3.3V microcontroller? Yes, the DVR8825 is compatible with both 3.3V and 5V logic levels.