Hello,

I have an audio project involving I2S that I've developed with a Teensy 3.2. It works perfectly.

My next step is to roll this into a simplified custom pcb. I'm happy to iterate this a few times.

I want the board powered by the USB bus, but using the MK20 in built regulator as I don't need to power anything else (beyond the MKL04). I've struggled to find reference diagrams for this but I've had a go - would appreciate some feedback.

I have no need for the analog IO - so how much of the pins like VDDA, VREFH, VREF_OUT, VREFL, VSSA do I need to bother with?

I also want to swap the USB connector for a USB-C. This is fine, I'm happy with that apart from the Mini USB pin 4, which goes to both MK20 and MKL4, but this is used for OTG things, so can I skip this when I swap for USB-C?

My work in progress schematic:
Click image for larger version. 

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