PWM DAC mode fast or phase correct?

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Hello,

I am considering micro-stepping a motor with an Allegro chip. One of the inputs to the chip can be used to set the limit of the coil current in one of the coils. I would like to generate these voltages (one for each coil current control) with an AVR using PWM. The voltages should remain stable for the time of one micro-step. The micro-steps are long, maybe 1 mS each, so they will include many timer cycles at the same duty cycle.

Theoretically, the fast PWM method requires less filtering than the phase correct method. Dean's tutorial says phase correct is important for motor control, but in this application is doesn't seem to me to matter much.

Should I use fast PWM, phase correct PWM, or does it make much difference?

Regards,

John