YOU WILL NEED THIS BOARD

Servo PWM Pi
16 Channel 12-bit PWM and Servo Driver with I2C interface using PCA9685 for driving LEDs and RC servos
£7.59 ex VAT
The Servo PWM Pi is a 16-channel, 12-bit PWM controller for the Raspberry Pi and other compatible single-board computers, suitable for driving LEDs and radio control servos. The board is based around PCA9685 PWM I2C LED controller IC from NXT and can drive each of the 16 outputs with a 12-bit (4096 steps) duty cycle from 0% to 100%.
The output frequency is programmable from a typical 40Hz to 1000Hz. Each output driver is programmed to be either open-drain with a 22 mA current sink capability at 5 V or totem pole with a 22 mA sink, 10 mA source capability at 5 V. 220R current limiting resistors are used on each channel, allowing you to connect servos or LEDs directly to the outputs.
This knowledge base section contains articles and tutorials on the Servo PWM Pi, showing how to use the development board.
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