Specifications

20 Gear Drive, Plymouth Ind. Park, Terryville, CT 06786
Tel: [phone] Fax: [phone] http://www.amci.com
CHOOSING YOUR SETTINGS
3
23
DIP Switch Settings (continued)
Step Resolution (SB3-1,2,3,4)
The SD17063 offers sixteen step resolutions.
Based on a 1.8° per step motor, figure 3.5 lists
the available step resolutions along with the
amount of rotation per indexer pulse.
The resolution that you should choose is
dependent on your application and equip-
ment. Full step resolution usually offers
slightly better torque at high speeds, but
microstepping offers smoother operation at all
speeds.
If you’re using the stepper motor to position a
load, you may be able to use step resolution to
simplify your indexer programming. An
example of this is setting the step resolution
to 36,000 when you want to rotate a table with
0.1° resolution. With this setting, the table
will theoretically rotate 0.1° for every ten
pulses applied to the drive. The actual
amount of rotation, and its final position,
depends on the motor and the holding torque
it must generate, so position feedback to the
indexer may still be necessary to accurately
position the load.
When determining your step resolution, make
sure you do not exceed the capabilities of
your indexer. For example, assume your
motor must rotate at thirty revolutions per
second and the maximum output frequency
from the indexer is 250,000 pulses per sec-
ond. Dividing 250,000 pps by 30 rps equals
8,333.3 pulses per revolution. Therefore, the
upper limit for the resolution setting is 5,000
steps per revolution. If you set the step reso-
lution to 10,000 steps per turn or higher you
will not be able to achieve your required
speed because the indexer cannot output
pulses fast enough.
The SD17063 has a maximum input fre-
quency of 2 MHz. It has been extensively
tested to motor speeds of fifty revolutions per
second at all step resolutions.
The state of these switches is latched on power up. Therefore, you must cycle power to the
drive or activate the Reset Input before the drive recognizes a change to this setting.
Figure 3.5 Step Resolution Switch Settings
12345
SB2
O
N
12345
SB3
O
N
12345
SB4
O
N
12345
SB1
O
N
Step Resolution
Switch Block 3: Switches 1 – 4
200 Steps/Rev
(FULL)
or SELF TEST1
400 Steps/Rev
(HALF)
1,000 Steps/Rev
(1/5)
2,000 Steps/Rev
(1/10)
5,000 Steps/Rev
(1/25)
10,000 Steps/Rev
(1/50)
12,800 Steps/Rev
(1/64)
18,000 Steps/Rev
(0.02°)
21,600 Steps/Rev
(1 arc min.)
25,000 Steps/Rev
(1/125)
25,400 Steps/Rev
(1/127)
25,600 Steps/Rev
(1/128)
36,000 Steps/Rev
(0.01°)
50,000 Steps/Rev
(1/250)
50,800 Steps/Rev
(1/254)
20,000 Steps/Rev
(1/100)
= Not Used When Setting Step Resolution
1
1) Self Test Mode is selected when the Step Resolu-
tion switches are set to 200 S/Rev, Anti-Resonance is
disabled, and the Output Waveform switches are set
to -4%, -6%, or -10% 3
rd
harmonic.