I am researching a way to generate PWM for 7 independent DC motor drivers, each connected to a 12 V DC motor. The drivers take in a PWM signal, a direction signal and a 12 V DC supply and use this to control the speed of the motors.
Currently, the design uses the Adafruit 16-Channel 12-bit PWM/Servo Driver board, based on the PCA9685 IC to generate multiple PWM signals from only one Arduino 101 (via the I2C bus). The issue with this IC and boards based on this IC is that the maximum possible PWM frequency that it can generate (1600 Hz) produces an audible hum from the motors when active.
It would be better to have a PWM generating circuit that can generate PWM at ~25 kHz, where it would be outside the audible frequency range. The circuit must be controlled by an Arduino, as this is the platform that existing software has been developed for.
Are there any pre-made circuit boards or integrated circuits that would allow this functionality?