DRV8886AT: Detecting stepper motor 2 by Back EMF

Part Number:DRV8886AT

Hello,

I am using your stepper motor driver, DRV8886AT, to drive stepper motor 1 and want to detect stepper motor 2 by Back EMF. Motor 1 and motor 2 are contacted by a gear. Do we have a devices for this application?

Regards,

David