• Wide Compatibility: Supports ST/SC series serial bus servos, making it versatile for various robot projects.
• Flexible Control: Offers UART and USB dual-mode communication, allowing easy control of multiple servos.
• Professional Power Supply: Equipped with a 2P 3.5mm screw terminal for secure and reliable power connections.
• Compact Design: Measures only 42mm x 25mm, ideal for integration into space-constrained projects.
• Ecosystem Support: Seamlessly integrates with Seeed Studio XIAO series development boards for expanded functionality.

What is the Bus Servo Driver Board?

The Bus Servo Driver Board is a serial bus servo driver designed to manage and control servos operating on serial communication protocols (such as the ST/SC series). Through integrated control circuitry and communication interfaces, it converts user commands into servo actions, enabling coordinated multi-servo operation. Unlike traditional PWM control, serial bus technology provides more efficient communication and greater scalability, making it particularly suited for robotics projects requiring multiple servos. This driver board offers both UART and USB control options, allowing users to choose between embedded system integration or convenient desktop debugging based on their needs.

Advantages of the Bus Servo Driver Board

Compared to other servo control solutions, the Bus Servo Driver Board stands out with distinct advantages. First, its compact 42mm x 25mm size and elegant design make it easy to integrate into space-constrained projects without compromising performance. Second, its dual-mode communication (UART and USB) balances real-time performance with ease of use—users can embed it into complex systems via UART or perform rapid debugging via USB, eliminating cumbersome wiring. Additionally, it supports control of multiple servos with angle and load feedback, outperforming single-servo controllers in multi-degree-of-freedom applications. Paired with the Seeed Studio XIAO ecosystem, developers can quickly build feature-rich robotic systems, reducing the time from concept to prototype. Whether for education, research, or DIY creation, this driver board excels with its professional performance and user-friendliness.

Q: How do I power the Bus Servo Driver Board?

A: Connect the power supply via the onboard 2P 3.5mm screw terminal. The input voltage range is 5-12V DC, which must match the rated voltage of the servos used and provide sufficient current to support all connected servos during operation.

Q: How do I connect servos and control devices to the board?

A: Servos are connected to the driver board via the 2.5mm 3P terminal, ensuring proper wiring (power, ground, signal lines). Control devices can be connected to a computer via the USB interface or to a microcontroller via the UART interface, with the specific mode determined by the jumper settings.

Q: How many servos can this driver board control?

A: It can control multiple ST/SC series serial bus servos, with the exact number depending on the power supply capacity and bus load conditions. Theoretically, it supports a large number of servos working together.

Q: What’s the difference between USB and UART modes, and how do I choose?

A: USB mode is plug-and-play, ideal for quick debugging and PC-based control; UART mode offers higher real-time performance, suitable for embedded system integration. Choose based on your application: USB for debugging, UART for embedded projects.

Note Change Record

2026/8/20, a 51 Ω resistor in a 0402 package and a TVS diode in a SOD-123 package have been added to suppress voltage overshoot.

• Supports serial bus servo driving for robotic arms (such as the SO-ARM100 Low-Cost AI Arm Servo Motor Kit for LeRobot and SO-ARM100 Low-Cost AI Arm Servo Motor Kit Pro for LeRobot).

• In order to use the servo driver board to control Feetech servos without XIAO, you would need following rework Stepsa. Short out JP1 and JP2 respectively

• 
• b. Add jumper to following pin header
• 
• Enables servo control in hexapod robots.
• Provides servo driving for humanoid robots.
• Assists wheeled robots with servo support.
• Facilitates servo use in DIY and educational projects.