Overview
The Yahboom SG90 servo motor steering gear is a 9g micro servo designed for PWM pulse-width control in compact motion projects. It uses a 3-pin interface (VCC, GND, IO), supports a 0–180° rotation range, and is intended for electronic DIY, smart cars, robots, and robotic arms.
For wiring or selection help, contact support@rcdrone.top or visit https://rcdrone.top/.
Key Features
- 9g servo collection: fast response / high efficiency / long life
- Three-wire control interface: VCC, GND, IO
- PWM pulse width control; pulse width range 500–2500 us corresponding to 0–180° (model-dependent parameters listed below)
- 180° large rotation angle
- Digital servo MCU control description: internal microprocessor amplifies 50 pulses/s signal to 300 pulses/s to improve response; reduces dead band for less jitter and improved accuracy/holding power
- Power protection description (availability depends on version): if the servo remains locked for more than 5 seconds, the power supply is cut off to protect the motor and prolong service life (noted as available for the 9G black metal servo and black plastic high quality servo)
- Recommended to use with a servo controller (accessory)
Specifications
| Parameter | 9G Plastic Digital Servo (Classic) | 9G Plastic Digital Servo (High quality) (YB-SG90) | 9G Metal Digital Servo |
|---|---|---|---|
| Working voltage | 4.8–6.0V DC | 4.8–6.0V DC | 4.8–6.0V DC |
| No load current | 90 mA (4.8V) | 80 mA (4.8V) | 150 mA (4.8V) |
| No load speed | 0.13 sec/60° (4.8V) | 0.14 sec/60° (4.8V) | 0.13 sec/60° (4.8V) |
| Locked rotor torque | 1.3 kgf.cm (4.8V) | 1.3 kgf.cm (4.8V) | 1.3 kgf.cm (4.8V) |
| Locked rotor current | 750 mA (4.8V) | 650 mA (4.8V) | 700 mA (4.8V) |
| Pulse width range | 500–2500 us corresponding 0–180° | 500–2500 us corresponding 0–180° | 500–2500 us corresponding 0–180° |
| Angle accuracy | 180° ± 3° | 180° ± 1° | 180° ± 1° |
| Dead band width | 8 us | 3 us | 3 us |
| Rocker arm type | 20T / Φ4.9 mm | 40T / Φ4.9 mm | 40T / Φ4.85 mm |
| Servo line length | 250 mm ± 5 mm | 245 mm ± 5 mm | 245 mm ± 5 mm |
| Gear material | Plastic gear | Plastic gear | Metal gear |
| Output shaft material | Plastic shaft | Plastic shaft | Metal shaft |
| Shell material | ABS | ABS | ABS |
| Control mode | PWM pulse width control | PWM pulse width control | PWM pulse width control |
| Work life | 200,000 cycles (Min) | 1,000,000 cycles (Min) | 500,000 cycles (Min) |
| Weight | 9 ± 0.5 g | 10 ± 0.5 g | 13.5 ± 0.5 g |
| Characteristic | Affordable, cost-effective | Silent, high precision, long service life | Metal gear, high precision, high strength and long service life |
Product Size (dimensions shown)
- These three servos have the same size.
- Values shown: 32.50, 27.80, 8.56, 12.00, Φ2.20, 23.0, 16.30, 23.20, 27.30 (unit not specified).
PWM Control Signal Reference
- Input signal pulse width (cycle: 20 ms)
- 0.5 ms → 0°
- 1.0 ms → 45°
- 1.5 ms → 90°
- 2.0 ms → 135°
- 2.5 ms → 180°
Applications
- Electronic creative experiment / electronic DIY
- Smart car, RC car
- Robot, robotic arm
Tutorials / Documents
Yahboom tutorial link: https://www.yahboom.net/study/SG90-Servo. The provided materials are described to include development board drive code and related tutorials (Arduino, micro:bit, MSPM0, Raspberry Pi Pico, Raspberry Pi, STM32), and routines described as based on the MSPM0G3507 microcontroller with documentation for KEIL and CCS routines.
Packing List
Packing list details are not specified in the provided text.
Details

Three 9g micro servo options cover everything from budget builds to higher-precision or stronger gear setups.

Compare working voltage, speed, torque, and gear materials across the 9g digital servo variants to pick the right one.

Standard SG90-size dimensions help confirm fit for brackets, robot arms, and small steering mounts.

Choose classic plastic for cost, high-quality plastic for better precision and lower noise, or metal gear for tougher loads.

Digital MCU control improves responsiveness and reduces jitter for smoother motion and steadier holding.

PWM pulse width maps directly to the output angle for straightforward 0–180° position control.

Pairing a servo controller makes it easier to test angles, endpoints, and direction before installing in a project.




Gear material affects durability and load handling—plastic for light duty, metal for higher stress applications.

Some versions add lock-rotor power protection to help prevent damage during stalls and extend service life.

A compact 9g servo is a common choice for DIY robotics, smart cars, and small actuator mechanisms.



Real product views highlight the 3-wire lead and the standard 9g micro servo form factor across versions.

Each kit includes the servo plus mounting screws and a set of horns for common linkage and bracket installs.


The Yahboom SG90M micro servo comes with three mounting screws and three servo horns for straightforward installation and linkage setups.
