PCA9685 contain an I2C-controlled PWM driver with a built-in clock.
5V compliant, which means you can control it from a 3.3V microcontroller and still safely drive up to 6V outputs.
Support using only two pins to control 16 free-running PWM outputs .
3 pin connectors in groups of 4, so you can plug in 16 servos at one time .
12-bit resolution for each output – for servos, that means about 4us resolution at 60Hz update rate.