Product introduction:This expansion board is a full-featured robot expansion version on market that can support multiple motors/stepper motors/servos (Stepper/Motor/Servo) at the same time,and can be stacked to expand more control interfaces.It's especially fit for various applications such as DIY robots,smart cars,robotic arms, smart pan/tilts,etc.The control interface simply adopts the I2C interface and is compatible with 3.3/5V levels,so it's also fit for other development boards on market. note: Due to different batches, the appearance, color, and printed words of the product may vary, which does not affect its use. Features: 1. Single power supply, the normal working power supply voltage range is 5V-12V; (Please select the correct input power supply voltage and current according to the motor control voltage you control) 2. Complete data input/output through the I2C bus of for the Raspberry Pi, 3. One I2C interface, compatible with 5V level, can be controlled by for Arduino or other development boards 4. One I2C interface can be connected to various sensors to expand various applications 5. The address of the expansion board is determined by 4 address pins, and a maximum of 16 expansion boards can be used at the same time. 6. Supports 16 PWM channel outputs and can control 16 servos or LED lights. 7. 12-bit resolution, adjustable PWM frequency up to 1.6KHz, configurable push-pull or open-drain output 8. Supports 4-way servo interface and 3P standard interface to facilitate connection of servo and LED lights. 9. Supports 2-channel 6V-12V stepper motors, Supports 4-channel 6V-12V reduction motors 10. Support infrared receiving function for convenient infrared control spec: Working voltage: 5V-12V Interface: I2C interface description: 1. 4-way servo interface ( 0, 1, 14, 15) 2. 4-way motor interface (M1, M2, M3, M4) 3. 2-way stepper motor interface (M1andM2, M3andM4) 4. I2C interface size: 65 x 56 x 21mm Material: PCB colour: blue Package Contents: 1 x Expansion Board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.