How to Use Servo MG90S: Examples, Pinouts, and Specs

The MG90S is a small, lightweight servo motor commonly used in robotics and hobby projects. It features a metal gear for improved durability and provides precise control of angular position, making it ideal for applications requiring movement and positioning. This servo motor is widely appreciated for its reliability, compact size, and ease of use.

• Robotic arms and grippers
• RC vehicles (cars, boats, planes)
• Pan-tilt camera systems
• Automated mechanisms and animatronics
• Educational and DIY electronics projects

The MG90S servo motor is designed to deliver high performance in a compact form factor. Below are its key technical details:

The MG90S servo motor has a 3-wire connector with the following pinout:

1. Power Supply: Ensure the servo is powered by a stable 4.8V–6.0V source. For best performance, use an external power supply if the servo draws more current than your microcontroller can provide.
2. Wiring:
   • Connect the brown wire to the ground (GND) pin of your microcontroller or power supply.
   • Connect the red wire to the 5V or 6V power source.
   • Connect the orange wire to a PWM-capable pin on your microcontroller.

The MG90S can be controlled using the Arduino Servo library. Below is an example code to rotate the servo to specific angles:

#include <Servo.h> // Include the Servo library

Servo myServo; // Create a Servo object to control the MG90S

void setup() {
  myServo.attach(9); // Attach the servo signal pin to Arduino pin 9
}

void loop() {
  myServo.write(0); // Move the servo to 0 degrees
  delay(1000);      // Wait for 1 second

  myServo.write(90); // Move the servo to 90 degrees
  delay(1000);       // Wait for 1 second

  myServo.write(180); // Move the servo to 180 degrees
  delay(1000);        // Wait for 1 second
}

• Avoid Overloading: Do not exceed the torque rating of the servo to prevent damage to the motor or gears.
• Use Proper Power Supply: If using multiple servos, ensure the power supply can handle the combined current draw.
• PWM Signal: Ensure the PWM signal is within the specified range (500 µs to 2500 µs) to avoid erratic behavior.
• Mechanical Limits: Avoid forcing the servo beyond its physical rotation limits (0° to 180°).

1. Servo Not Moving:

   • Cause: Incorrect wiring or insufficient power supply.
   • Solution: Double-check the wiring and ensure the power supply provides adequate voltage and current.

2. Erratic Movement:

   • Cause: Noisy or unstable PWM signal.
   • Solution: Use a clean PWM signal from a microcontroller or servo controller.

3. Overheating:

   • Cause: Prolonged operation under high torque or stalled conditions.
   • Solution: Avoid stalling the servo and ensure it operates within its torque limits.

4. Limited Rotation:

   • Cause: Servo is designed for 180° rotation.
   • Solution: This is normal behavior. If continuous rotation is needed, use a continuous rotation servo.

Q: Can the MG90S be powered directly from an Arduino UNO?
A: While the MG90S can be powered from the Arduino's 5V pin, it is recommended to use an external power supply for reliable operation, especially if multiple servos are used.

Q: What happens if I send a PWM signal outside the specified range?
A: Sending a PWM signal outside the 500 µs to 2500 µs range may cause the servo to behave unpredictably or stop responding.

Q: Can the MG90S rotate more than 180°?
A: No, the MG90S is designed for a maximum rotation angle of 180°. For continuous rotation, consider using a different type of servo.

Q: How much current does the MG90S draw?
A: The current draw depends on the load. Under no load, it typically draws around 10–100 mA, but under high torque, it can draw up to 700 mA.

By following this documentation, you can effectively integrate the MG90S servo motor into your projects and troubleshoot common issues with ease.