DS90UB935-Q1: can 935 support 12bit 48k sample rate I2S?

Hello Jiawei,

Yes it should be possible based on the max allowable FC GPIO rates of 935. You can reference this app note for I2S considerations and there is a table on page 5 which shows some example supported rates 

https://www.ti.com/lit/an/snla314a/snla314a.pdf?ts=1631077594316&ref_url=https%253A%252F%252Fwww.google.com%252F 

Best Regards,

Casey