How to Use DRV8825: Examples, Pinouts, and Specs

Introduction

The DRV8825 is a high-performance stepper motor driver designed for precise control of bipolar stepper motors. It features adjustable current control, microstepping capabilities (up to 1/32 steps), and can handle up to 2.5A per phase with proper cooling. This makes it an ideal choice for applications requiring smooth and accurate motor control, such as 3D printers, CNC machines, and robotics. Its compact design and ease of integration make it a popular choice among hobbyists and professionals alike.

Explore Projects Built with DRV8825

ATmega328P Microcontroller-Driven Stepper Motor with DRV8825

This circuit is designed to control a bipolar stepper motor using a DRV8825 stepper motor driver, which is interfaced with a Nano 3.0 ATmega328P microcontroller. The microcontroller sends step and direction signals to the DRV8825, which in turn drives the stepper motor's coils. Power is supplied to the system through a 5V adapter for the logic and a DC power source for the motor, with an electrolytic capacitor for voltage smoothing on the motor supply.

Open Project in Cirkit Designer

ESP32-Controlled Miniature Golf Course with Interactive Features

This circuit is designed for an interactive miniature golf course feature, which includes a stepper motor controlled by a DRV8825 driver for a rotating windmill obstacle, two IR sensors for detecting the presence of a golf ball, and two LED strips for visual effects. An ESP32 microcontroller is programmed to manage the sensors, control the stepper motor, drive the LED strips, and interface with a DFPlayer Mini MP3 module for sound effects. The circuit is powered by a 12V power supply with a buck converter to step down the voltage for the logic components, and electrolytic capacitors are used for voltage smoothing.

Open Project in Cirkit Designer

ESP32-Powered Wi-Fi Controlled Robotic Car with OLED Display and Ultrasonic Sensor

This circuit is a battery-powered system featuring an ESP32 microcontroller that controls an OLED display, a motor driver for two hobby motors, an ultrasonic sensor for distance measurement, and a DFPlayer Mini for audio output through a loudspeaker. The TP4056 module manages battery charging, and a step-up boost converter provides a stable 5V supply to the components.

Open Project in Cirkit Designer

ESP32-Controlled Weather Station with BME280 Sensor and Rain Detection

This circuit features an ESP32 microcontroller interfaced with a DRV8825 stepper motor driver to control a bipolar stepper motor, an Adafruit BME280 sensor for environmental monitoring, and a YL-83 rain sensor for detecting precipitation. The ESP32 uses I2C communication to interact with the BME280 sensor and digital/analog signals to read from the rain sensor's control board. Power management is handled by a solar charger power bank connected to the DRV8825 and a capacitor for voltage smoothing.

Open Project in Cirkit Designer

Technical Specifications

Motor Type Supported: Bipolar stepper motors
Operating Voltage: 8.2V to 45V
Maximum Current: 2.5A per phase (with sufficient cooling)
Microstepping: Full-step, 1/2, 1/4, 1/8, 1/16, and 1/32 steps
Logic Voltage: 3.3V or 5V compatible
Thermal Shutdown: Built-in over-temperature protection
Overcurrent Protection: Built-in short-to-ground and shorted-load protection
Dimensions: 15mm x 20mm (approx.)

Pin Configuration and Descriptions

The DRV8825 module has 16 pins. Below is the pinout and description:

Pin	Name	Description
1	VMOT	Motor power supply (8.2V to 45V). Connect to the stepper motor power source.
2	GND	Ground for motor power supply.
3	B2	Motor coil B output 2.
4	B1	Motor coil B output 1.
5	A1	Motor coil A output 1.
6	A2	Motor coil A output 2.
7	GND	Ground for logic power supply.
8	VDD	Logic power supply (3.3V or 5V).
9	ENABLE	Enable/disable the driver (active low).
10	MS1	Microstepping resolution selector (see table below).
11	MS2	Microstepping resolution selector (see table below).
12	MS3	Microstepping resolution selector (see table below).
13	RESET	Resets the driver (active low).
14	SLEEP	Puts the driver into low-power sleep mode (active low).
15	STEP	Step input. Each pulse moves the motor one step.
16	DIR	Direction input. Determines the rotation direction of the motor.

Microstepping Resolution Table

The microstepping resolution is configured using the MS1, MS2, and MS3 pins:

MS1	MS2	MS3	Microstepping Mode
Low	Low	Low	Full Step
High	Low	Low	1/2 Step
Low	High	Low	1/4 Step
High	High	Low	1/8 Step
Low	Low	High	1/16 Step
High	Low	High	1/32 Step

Usage Instructions

Connecting the DRV8825 to a Stepper Motor

Power Supply: Connect the VMOT pin to the motor power supply (8.2V to 45V) and the GND pin to the power ground.
Motor Connections: Connect the stepper motor coils to the A1, A2, B1, and B2 pins. Ensure the correct pairing of the motor wires.
Logic Power: Connect the VDD pin to the logic power supply (3.3V or 5V) and the GND pin to the logic ground.
Control Pins: Connect the STEP and DIR pins to your microcontroller or control circuit. Use the ENABLE pin to enable or disable the driver.
Microstepping: Configure the MS1, MS2, and MS3 pins to set the desired microstepping resolution.
Current Adjustment: Use the onboard potentiometer to adjust the current limit. This prevents overheating and ensures optimal motor performance.

Example: Using DRV8825 with Arduino UNO

Below is an example code to control a stepper motor using the DRV8825 and Arduino UNO:

// Define the control pins for the DRV8825
#define STEP_PIN 3  // Connect to the STEP pin of DRV8825
#define DIR_PIN 4   // Connect to the DIR pin of DRV8825

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 = clockwise)
}

void loop() {
  // Generate a pulse to move the motor one step
  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
}

Important Considerations

Cooling: If driving motors at high currents, ensure proper cooling (e.g., heatsinks or fans) to prevent overheating.
Current Limit: Always set the current limit to match your motor's rated current to avoid damage.
Power Sequence: Always connect the logic power (VDD) before the motor power (VMOT) to prevent damage to the driver.
Decoupling Capacitors: Add a capacitor (e.g., 100µF) across VMOT and GND to reduce voltage spikes.

Troubleshooting and FAQs

Common Issues

Motor Not Moving:
- Check the wiring of the motor coils (A1, A2, B1, B2).
- Verify the STEP and DIR signals from the microcontroller.
- Ensure the ENABLE pin is set to LOW.
Overheating:
- Ensure the current limit is set correctly using the potentiometer.
- Add a heatsink or fan for better cooling.
Erratic Motor Movement:
- Check the microstepping configuration (MS1, MS2, MS3).
- Verify the power supply voltage and current rating.
Driver Not Responding:
- Ensure the RESET and SLEEP pins are not held LOW.
- Verify the logic power (VDD) and motor power (VMOT) connections.

FAQs

Q: Can I use the DRV8825 with a unipolar stepper motor?
A: No, the DRV8825 is designed for bipolar stepper motors only.

Q: How do I calculate the current limit?
A: Use the formula: Current Limit = VREF / (8 * R_sense). For most DRV8825 modules, R_sense is 0.1Ω.

Q: What happens if I exceed the maximum current rating?
A: The driver may overheat or trigger overcurrent protection, potentially damaging the module.

Q: Can I daisy-chain multiple DRV8825 drivers?
A: Yes, you can control multiple drivers using separate STEP and DIR signals for each motor.

By following this documentation, you can effectively integrate the DRV8825 into your projects for precise and reliable stepper motor control.