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

The MG90S is a small, lightweight servo motor widely used in robotics, RC vehicles, and hobby projects. It features a durable metal gear system, ensuring improved precision and longevity compared to plastic gear servos. The MG90S operates within a voltage range of 4.8V to 6.0V and provides a rotation angle of approximately 180 degrees. Its compact size and reliable performance make it an excellent choice for applications where space is limited and precise control is required.

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

Below are the key technical details of the MG90S servo motor:

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

1. Power Supply: Connect the red wire to a 5V power source (or 6V for higher torque). Ensure the power supply can provide sufficient current (at least 1A is recommended).
2. Ground: Connect the brown wire to the ground (GND) of your circuit.
3. Signal: Connect the orange wire to a PWM-capable pin on your microcontroller (e.g., Arduino).

• Voltage Range: Do not exceed the 6.0V maximum operating voltage to avoid damaging the servo.
• Current Requirements: Ensure your power supply can handle the current draw, especially under load.
• PWM Signal: The MG90S requires a PWM signal with a pulse width between 1 ms (0°) and 2 ms (180°). A 1.5 ms pulse corresponds to the neutral position (90°).
• Mechanical Limits: Avoid forcing the servo beyond its physical rotation limits to prevent damage.

Below is an example code to control the MG90S servo motor using an Arduino UNO:

#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 to pin 9 on the Arduino
}

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
}

• Use a dedicated power supply for the servo if your circuit includes multiple components to avoid voltage drops.
• Secure the servo firmly in place to prevent vibrations or misalignment during operation.
• Calibrate the servo's range of motion in your code to ensure it operates within safe limits.

1. Servo Not Moving

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

2. Servo Jittering

   • Cause: Electrical noise or unstable power supply.
   • Solution: Use a capacitor (e.g., 100 µF) across the power and ground lines to stabilize the voltage.

3. Servo Overheating

   • Cause: Prolonged operation under heavy load or exceeding voltage limits.
   • Solution: Reduce the load on the servo or ensure the operating voltage is within the specified range.

4. Limited Rotation

   • Cause: Incorrect PWM signal or mechanical obstruction.
   • Solution: Verify the PWM signal timing and ensure there are no physical obstructions.

Q: Can the MG90S rotate continuously?
A: No, the MG90S is a standard servo with a rotation range of approximately 180°. For continuous rotation, use a continuous rotation servo.

Q: Can I power the MG90S directly from the Arduino?
A: While possible, it is not recommended as the Arduino's 5V pin may not provide sufficient current under load. Use an external power supply for reliable operation.

Q: How do I know if the servo is receiving a signal?
A: The servo will typically make a slight noise or move to its default position when powered and receiving a valid PWM signal.

Q: Can I use the MG90S with a Raspberry Pi?
A: Yes, but you will need to generate a PWM signal using a library like RPi.GPIO or an external PWM controller for precise control.