APPLICATION NOTES CONTINUED
COMMUTATION TRUTH TABLE
HALL SENSOR PHASING
120°
60°
I
COMMAND
= POS.
I
COMMAND
= NEG.
BRAKE
HALL HALL HALL HALL HALL HALL
A
B
C
A
B
C
1
1
0
0
0
1
1
0
X
1
0
X
=
=
=
AØ
H
-
L
L
-
H
-
-
L
BØ
-
H
H
-
L
L
-
-
L
CØ
L
L
-
H
H
-
-
-
L
AØ
L
-
H
H
-
L
-
-
L
BØ
-
L
L
-
H
H
-
-
L
CØ
H
H
-
L
L
-
-
-
L
0
0
0
0
0
0
0
0
1
0
1
1
1
0
0
1
0
X
High Level
Low Level
Don't Care
0
0
0
1
1
1
1
0
X
H
L
-
1
1
1
0
0
0
1
0
X
0
1
1
1
0
0
0
1
X
0
0
1
1
1
0
1
0
X
NOTE:
= SOURCE
= SINK
= OPEN
Because of the true 4 quadrant method of output switching,
the output switches will PWM between the I
COMMAND
POSITIVE
and I
COMMAND
NEGATIVE states, with the average percentage
based on I
COMMAND
being a positive voltage and a negative
voltage. With a zero voltage I
COMMAND
, the output switches will
modulate with exactly a 50% duty cycle between the
I
COMMAND
POSITIVE and I
COMMAND
NEGATIVE states.
4
PRELIMINARY Rev. A 6/00
MSK [ M.S. KENNEDY CORPORATION ]
