PCA9685 16-Channel PWM Servo Driver Board | ATMOSFÆR ENGINEERING

I2C-controlled 16-channel servo driver with built-in PWM generator and clock - control up to 16 servos using only 2 GPIO pins. Features 12-bit resolution for smooth, precise servo movements without occupying your microcontroller. Includes 16 standard servo connectors, onboard 1000µF capacitor for stable power delivery, and chainable design for massive multi-servo projects like hexapods and robot arms.

Technical Specifications:

• IC: PCA9685 PWM Driver
• Interface: I2C (TWI)
• Servo Channels: 16 independent outputs
• Resolution: 12-bit (4096 steps) - 4µs precision @ 60Hz
• PWM Frequency: Adjustable, typically 50-60Hz for servos (up to 1.6kHz)
• Operating Voltage: 2.3V - 5.5V (logic)
• Servo Power (V+): 4.8V - 6V (external supply required)
• Output Current: 25mA per channel (control signal only)
• I2C Addresses: Configurable (up to 62 boards = 992 servos on one I2C bus)
• Servo Connectors: 16x standard 3-pin headers (0.1" pitch compatible)
• Onboard Capacitor: 1000µF 10V for power stability
• Protection: Reverse polarity protection, 220Ω series resistors
• Board Dimensions: 62mm x 25mm x 13mm
• Power Indicator: Green LED
• Operating Temperature: -40°C to +85°C

Features:

• Hardware PWM generator (no microcontroller timer usage)
• Control 16 servos with just 2 wires (SDA/SCL)
• 5V tolerant I2C (works with 3.3V and 5V microcontrollers)
• Plug-and-play servo headers (no soldering needed)
• Chainable via I2C address selection (up to 992 servos!)
• Onboard capacitor reduces servo jitter
• Output enable pin for emergency stop
• High resolution for smooth servo motion
• No PWM frequency drift (built-in clock)

Pin Configuration:

• VCC: Logic power (3.3V - 5V from microcontroller)
• V+: Servo power input (4.8V - 6V, external battery/supply)
• GND: Common ground
• SDA/SCL: I2C communication
• OE: Output enable (pull low to disable all servos)
• 16x Servo Headers: Standard 3-pin (Signal/VCC/GND)

Servo Connection:

• Simply plug servos into any of 16 headers
• Connect external 5V-6V power supply to V+ terminal
• Wire VCC to microcontroller logic voltage
• Connect SDA/SCL to microcontroller I2C pins

Applications:

• Hexapod/quadruped robots (6-18 servos)
• Robot arms and grippers (4-6 servos)
• Humanoid robots (12+ servos)
• RC vehicle control surfaces
• Camera pan-tilt gimbals (2-3 servos)
• Animatronics and props
• Multi-axis positioning systems
• Educational robotics projects

Expansion Capability:

• Chain up to 62 boards on single I2C bus
• Total capacity: 992 servos from 2 GPIO pins
• Perfect for complex multi-leg robots or large installations

Important Notes:

• Must use external power for servos - connect 4.8V-6V battery to V+ terminal
• Do NOT power servos from microcontroller voltage pin (insufficient current)
• Onboard 1000µF capacitor included for servo power stability
• Set PWM frequency to 50Hz for standard analog servos (60Hz for digital)
• All servos share same update frequency (independent positions)
• Reverse polarity protection on power input

Typical Setup:

1. Connect VCC to microcontroller logic voltage (3.3V or 5V)
2. Connect GND to microcontroller ground
3. Connect SDA/SCL to microcontroller I2C pins
4. Connect external 5-6V battery to V+ terminal (servos)
5. Plug servos into headers
6. Configure I2C driver in your firmware

Compatible with Arduino, ESP32, Raspberry Pi, STM32, PIC, AVR, ARM Cortex, and any microcontroller with I2C support. Libraries available for most platforms.