2-Phase Stepper Motor Bipolar Driver ICs (2W1-2 Phase Excitation/Micro-step Support)
A3955SB/SLB
sStep
Sequence
Bridge A
Full
Step
1
Half
Step
1
Quarter
Step
1
2
2
3
4
2
3
5
6
4
7
8
3
5
9
10
6
11
12
4
7
13
14
8
15
16
Eigth
Step
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
PHASE
A
H
H
H
H
X
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
X
H
H
H
H
H
H
H
H
H
H
H
D
2A
H
L
L
L
L
L
L
L
H
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
H
H
H
H
H
H
H
H
D
1A
L
H
H
L
L
L
H
H
L
L
H
H
H
H
H
L
L
H
H
L
L
L
H
H
L
L
H
H
H
H
H
L
D
0A
L
H
L
H
L
H
L
H
L
H
L
H
H
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
H
H
L
H
I
LOADA
70.7%
55.5%
38.2%
19.5%
0%
−19.5%
−38.2%
−55.5%
−70.7%
−83.1%
−92.4%
−100%
−100%
−100%
−92.4%
−83.1%
−70.7%
−55.5%
−38.2%
−19.5%
0%
19.5%
38.2%
55.5%
70.7%
83.1%
92.4%
100%
100%
100%
92.4%
83.1%
PHASE
B
H
H
H
H
H
H
H
H
H
H
H
H
X
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
X
H
H
H
D
2B
H
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
H
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
D
1B
L
L
H
H
H
H
H
L
L
H
H
L
L
L
H
H
L
L
H
H
H
H
H
L
L
H
H
L
L
L
H
H
D
0B
L
H
L
H
H
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
H
H
L
H
L
H
L
H
L
H
L
H
I
LOADB
70.7%
83.1%
92.4%
100%
100%
100%
92.4%
83.1%
70.7%
55.5%
38.2%
19.5%
0%
−19.5%
−38.2%
−55.5%
−70.7%
−83.1%
−92.4%
−100%
−100%
−100%
−92.4%
−83.1%
−70.7%
−55.5%
−38.2%
−19.5%
0%
19.5%
38.2%
55.5%
Bridge B
sCurrent
Vector Locus
A
100
92.4
83.1
TEP
MAXIMUM FULL-STEP
TORQUE (141%)
10
0%
1/4
STE
P
CURRENT IN PERCENT
3/
8
ST
70.7
C
O
N
ST
AN
T
1/8 S
EP
55.5
2
1/
EP
ST
TO
R
Q
U
E
5/
T
8S
EP
38.2
S
3/4
TE
P
19.5
7/8 S
TEP
B
19.5
A
38.2
55.5
FULL STEP
B
100
70.7
83.1 92.4
CURRENT IN PERCENT
A3955SB/SLB
91