A3981KLPTR-T Allegro Microsystems Inc, A3981KLPTR-T Datasheet - Page 28

• Manufacturer Part Number: A3981KLPTR-T
• Description: AUTOMOTIVE PROGRAMMABLE STEPPER DRVR
• Manufacturer: Allegro Microsystems Inc

Specifications of A3981KLPTR-T

• Applications: Stepper Motor Driver, 2 Phase
• Number Of Outputs: 1
• Voltage - Load: 7 V ~ 28 V
• Voltage - Supply: 3 V ~ 5.5 V
• Operating Temperature: -40°C ~ 150°C
• Mounting Type: Surface Mount
• Package / Case: 28-TSSOP (0.173", 4.40mm Width) Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

A3981
32/63=50.8% and so on. The value at each Step Angle Number is
then assigned to its corresponding phase table values as follows:
where DI
Angle Number n.
A selection of the values and the corresponding phase current
table entries is shown in figure12. The full set of phase current
table values is shown in the table below.
These 16 values are then loaded sequentially into the phase
current table through the Phase Table Load register of the serial
interface. Each value is then distributed to the appropriate Step
Angle Numbers as described above and as shown in table 4C in
the Phase Table Load Register section.
A representation of the final result is shown in figure 13. This
is the digitized version of the required current profile shown in
figure 13.
Value 10 20 25 28 29 30 31 32 35 40 50 58 60 62 63 63
Step
PT
n
represents the digitized value of the current at Step
1
0
2
1
3
2
4
3
5
4
PT
6
5

n
7
6
1

8
7

9 10 11 12 13 14 15 16
8
DI
n
9 10 11 12 13 14 15
Automotive, Programmable Stepper Driver
Figure 13. Resulting example current profile
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
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