CurrentControl
Phase
Control
One
Shot
Comp.
3718
+38V
A
R4 Typ
Phase
I0 current
I1 current
VREF
0v
5v
0.4v
30v
30v
≈ 2.7 mSec
00
U20 - 15
R4
J2 - 1
J2 – 3
A
B
C
D
Fig. 4.1 Stepper Motor Drive Circuit
B
0v
5v
0.4v
30v
30v
≈ 2.7 mSec
00
U20 - 15
R4
J2 - 1
J2 – 3
A
B
C
D
0v
5v
0.0v
0.4v
0v
38v
38v
≈ 2.7 mSec
00 ≈ 5.5 mSec
U20 - 15
R4
J2 - 1
J2 – 3
A
B
C
D0v
C
D