Most standard 4 lead 1.8 degree, two phase, hybrid stepping motors will operate with the DB drive. Phase current is resistor selectable.
Most motor manufactures specify current ratings with unipolar drive techniques. Bipolar drives provide double the current of unipolar drives with the same current setting. Divide the manufactures motor current rating by two to set the bipolar drive.
My Motors are:
Holding torque 425oz
Shaft diameter .25
Voltage 4v
Current 2.8A
Nema 23
Body size 60mm w X 86mm L most 270-280oz motors are 57mm w X 76 mm L
Wires 4 wire bipolar
Steps 200 steps per revolution
So Based on this I Think I still need to set the DB drive current to 2.8A with the correct resistor value. ( Since they are rated @ 2.8A 4Wire Bipolar )
Rather than dividing the 2.8A by 2 and setting it at 1.4A