PCA9685 Servo Controller Board – Precision Control for Model Railways

Smooth & Reliable Automation for Turnouts, Semaphores, and Signals

Bring your layout to life with the PCA9685 Servo Controller Board — the perfect solution for model railway automation. With the ability to control up to 16 independent servos or LED channels, this board makes it easy to motorize turnouts, animate semaphore signals, or illuminate block signals with smooth precision.

Need help setting it up? Follow our step-by-step DCC-EX servo controller configuration guide to get your turnouts, signals, and smooth servo movement working correctly with the PCA9685.

✅ Key Benefits for Railway Modelers

• Effortless turnout control – smoothly operate up to 16 turnouts with realistic motion.
• Animate semaphores – replicate the graceful movement of mechanical signals with fine PWM control.
• Control signal lights – use PWM dimming for prototypical lighting effects.
• Expandable design – daisy-chain multiple boards to manage large layouts with hundreds of outputs.
• Seamless integration – works with Arduino, Raspberry Pi, DCC++/EX, and other layout control systems.
• Independent power supply – run your servos and lights without overloading your main controller.

🔧 Technical Specifications

• Controller Chip: PCA9685
• Channels: 16 independent PWM outputs
• Resolution: 12-bit (4096 steps)
• Frequency Range: Adjustable from 24Hz to 1526Hz
• Interface: I²C (only 2 wires needed from your controller)
• Input Voltage: 5V logic / up to 6V servo power
• I²C Addressing: 62 possible addresses (control nearly 1,000 servos!)
• Size: ~62mm x 26mm – compact enough to mount under your baseboard

💡 Why Model Railway Hobbyists Love It

Traditional turnout motors and relays can be noisy, abrupt, or power-hungry. The PCA9685 Servo Controller offers:

• Realistic movement – replicate the slow sweep of real turnouts and semaphores.
• Quiet operation – servos move smoothly without the “clunk” of solenoids.
• Scalable layouts – expand control without re-wiring your entire system.
• Prototypical lighting – fade LEDs for authentic signal aspects and yard lighting.

Perfect for:

• Turnout (point) control
• Semaphore signals
• Colour-light signal masts
• Animated level crossings
• Station building lighting