Adafruit 16-Channel 12-bit PWM/Servo Driver - I2C interface (PCA9685)

This is a versatile PWM and Servo driver breakout board designed for projects that require precise control of multiple PWM outputs, such as creating a robot or controlling a lot of LEDs. It allows you to control 16 PWM outputs with only two pins and even chain up to 62 breakouts, giving you a total of 992 PWM outputs.

The board uses I2C to control the PWM driver, which has a built-in clock, so you don't need to continuously send data, freeing up your microcontroller for other tasks. It’s compatible with 5V systems and can be used with 3.3V microcontrollers. It’s also capable of sinking up to 5.5V outputs, which is useful for controlling high-voltage LEDs.

This breakout board is equipped with six address select pins for easy chaining, adjustable PWM frequencies up to 1.6 kHz, and 12-bit resolution for each output. The resolution is particularly useful for servo control, providing about 4µs precision at a 60Hz update rate. The outputs can be configured in push-pull or open-drain mode, and there’s a pin to quickly disable all outputs.

Additional features include a terminal block for power input, reverse polarity protection, and a green power-good LED. The design also includes a place for adding a large capacitor if needed, and 220-ohm resistors on each output line for protection, making it easy to drive LEDs. The breakout board also includes solder jumpers for address selection and connectors for servos and LEDs.

The product comes fully assembled and tested, and it includes headers and a terminal block for easy assembly. A bit of soldering is required to attach the headers, a simple task even for beginners. This board is ideal for controlling multiple servos or LEDs in a compact and efficient manner.

Specifications:

• Dimensions: 2.5" x 1" x 0.1" (62.5mm x 25.4mm x 3mm)
• Weight: 5.5g (without headers or terminal block), 9g (with headers & terminal block)
• I2C address range: 0x40–0x7F (selectable via jumpers)
• Adjustable PWM frequency: up to 1.6 kHz
• 12-bit PWM resolution per output
• Includes EagleCAD files, datasheets, and Fritzing object in the tutorial

Revision History:

• December 20, 2022: PCB updated with a legible silkscreen (Pinguin version)
• February 16, 2015: Beefier polarity-protection transistor added, with no change in functionality.