Hi guys,
I'm looking for a I2C PWM Expander with individual PWM Frequencies for each output of the Expander.
My plan is to run several Mosfets with different Loads and control them with this PWM Expander.
I found the Adafruit PWM Expander, but it only has a fixed Frequency for all Outputs.
My thoughts were to either group my mosfets and use the same chip as on the Adafruit Expander, cheap microcontrollers that may be able to handle this task or a specific chip that is capable of doing this.
Any recommendation is a help and appreciated! Advices on ICs would be awesome.
The Board you are recommending is exactly the board that I'm talking about in the initial post. It only supports one frequency for all outputs, not a individual frequency for each output.
This could mean 'several' PCA9685 boards.
They can be daisy-chained to theoretically about 60.
Don't know of any other PWM chips with variable PWM frequency an only one output.
Leo..
Right now I'm assuming to have 30 Mosfets. Ofc I could use multiple PCA9685 and group the mosfets for example as 250Hz, 1kHz, 10kHz, 25kHz. This would mean that there could be loads that are best suited at 100kHz and I would need to have one more PCA9685 just to handle that one. But It would be great if there is a IC that is like the PCA9685, but allows to set the PWM Frequency of each Output though I2C.
8 bit is not enough?
Anyway with some care it should be possible to write a program for a microcontroller to do something like that. If the frequency is too high it will handle only a few channels. OTOH if you may afford to use an ATMega for 6 channels it should be straightforward. I think HW I2C is a great advantage for such project and ATMega48 is very cheap on eBay.