Best solution to isolate LMD18245 from uController

Hi,

I'm planning to use LMD18245 to drive a Bipolar Stepper Motor (24V 1.8A 1.8°) with microstepping (quarter step drive with torque compensation).

Schematic that I plan to use is the same on datasheet

Below the functional block diagram reported for convenience

I have some question:

- What is the best solution to isolate Motor and Driver from micro controller? I am thinking using optocoupler with LMD18245 input but so I've to genere DAC REF from motor power supply that can be noisy when motor are running. There are better way?

- How can I use external DAC? There is only CS OUT and COMP OUT input, I need also an external comparator?

Thank you

Leonardo