I'm making a H-bridge for a 12V DC-motor. I have to choose a flyback diode but I have a hard time determining the motor's back EMF voltage. I'm assuming this voltage won't be more than double the supply voltage of 12.6V. The maximum current through the motor is 6A. I'm also assuming that my transistor Q5 should be on when changing the direction of the motor leaving a path for the current made from the back EMF to flow in. Is this correct?
I was also wondering if there is a need of some sort of decoupling when a high current is rushing to V_Batt?