Adafruit 16-Channel 12-bit PWM/Servo Driver - I2C interface [PCA9685] : ID 815 : $14.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Amazon.com: WWZMDiB PCA9685 16 Channel 12 bit PWM Servo Motor Driver I2C IIC Module for Arduino Raspberry Pi Zero/Zero W/Zero WH/2B/3B/3B+ and Robot : Electronics
PCA9685 16 Channel 12-bit PWM Servo motor Driver I2C Module For Servo – eElectronicParts