WSAL15275 – Servo Driver HAT/en

Documentation notice: This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.

Summary

The Servo Driver HAT adds 16 PWM/servo channels to a Raspberry Pi via the I2C interface. Control is handled by the PCA9685 driver IC with 12-bit resolution per channel.

Related products at JW Tech

Technical overview

Controlled over I2C; no extra GPIO pins required
16 channels, each with 12-bit resolution
Input supply: 6 V to 12 V at the green VIN terminal block
Logic voltage: 3.3 V; servo input voltage: 5 V
Dimensions: 65 mm × 30 mm; mounting hole diameter 3.0 mm
Jumpers A0–A4 select the PCA9685 I2C device address; different combinations allow multiple modules in parallel
Top pin headers: black = GND, red = 5 V, yellow = PWM signal
Maximum output current of the onboard regulator: 3 A
Compatible platforms per source: Raspberry Pi, Jetson Nano, VisionFive2

Commands and examples – verify before use:

sudo raspi-config
sudo reboot
sudo apt-get update
sudo apt-get install python-pip
sudo pip install RPi.GPIO
sudo apt-get install python-smbus
sudo apt-get install p7zip-full
wget https://www.waveshare.com/w/upload/6/6c/Servo_Driver_HAT.7z
7zr x Servo_Driver_HAT.7z -r -o./Servo_Driver_HAT
sudo chmod 777 -R Servo_Driver_HAT
cd Servo_Driver_HAT/Raspberry\ Pi/
cd python/
sudo python PCA9685.py
cd python3/
sudo python3 PCA9685.py
cd Wifi-Control/
sudo python main.py
sudo apt-get install pi-bluetooth bluez bluez-firmware blueman
sudo usermod -G bluetooth -a pi
sudo vi /etc/systemd/system/dbus-org.bluez.service

Notes and version constraints

When driving high-power servos, the Raspberry Pi's 5 V supply may be insufficient; remove the 0-ohm resistor and connect external 6–12 V to VIN
Precise angular positioning is only entry-level; highly accurate angle jumps are not guaranteed
If you observe jitter, squeaking or overheating, it is usually mechanical wear of the internal potentiometer
When stacking multiple modules, set jumpers A0–A4 so each unit gets a unique I2C address
Default Bluetooth discovery time is only 180 s; persistent discovery requires edits to /etc/bluetooth/main.conf
Some steps depend on the exact hardware revision (HAT vs HAT (B)) and may need manual confirmation

Source and revision record

Servo Driver HAT - Waveshare Wiki
Source revision: 79075
Captured: 2026-08-31T02:46:23+00:00
SHA-256: 3e6d6ebae2d4abf603c2f9727821bf5fa94ae80ebe0c4fdc7fdb4bd9cbe68fab