AMIS-30623

12.2 Maximum Velocity

For each stepping mode, the maximum velocity Vmax can be programmed to 16 possible values given in Table 8.

The accuracy of Vmax is derived from the internal oscillator. Under special circumstances it is possible to change the Vmax parameter

while a motion is ongoing. All 16 entries for the Vmax parameter are divided into four groups. When changing Vmax during a motion the

application must take care that the new Vmax parameter stays within the same group.

Table 8: Maximum Velocity Selection Table

Vmax Index

Stepping Mode

Hex

Dec

Vmax

(ull step/s)

Group

Half-stepping

(half-step/s)

1/4

th

Micro-stepping

(micro-step/s)

1/8

th

Micro-stepping

(micro-step/s)

1/16

th

Micro-stepping

(micro-step/s)

0

0

99

A

197

395

790

1579

1

1

136

273

546

1091

2182

2

2

167

334

668

1335

2670

3

3

197

395

790

1579

3159

4

4

213

425

851

1701

3403

5

5

228

456

912

1823

3647

6

6

243

B

486

973

1945

3891

7

7

273

546

1091

2182

4364

8

8

303

607

1213

2426

4852

9

9

334

668

1335

2670

5341

A

10

364

729

1457

2914

5829

B

11

395

790

1579

3159

6317

C

12

456

C

912

1823

3647

7294

D

13

546

1091

2182

4364

8728

E

14

729

1457

2914

5829

11658

F

15

973

D

1945

3891

7782

15564

12.3 Minimum Velocity

Once the maximum velocity is chosen, 16 possible values can be programmed for the minimum velocity Vmin.

Table 9 provides the obtainable values in full-step/s. The accuracy of Vmin is derived from the internal oscillator.

Table 9: Obtainable Values in Full-step/s for the Minimum Velocity

Vmax (Full-step/s)

Vmin Index

A

B

C

D

Hex

Dec

Vmax

Factor

99

136

167

197

213

228

243

273

303

334

364

395

456

546

729

973

0

0

1

99

136

167

197

213

228

243

273

303

334

364

395

456

546

729

973

1

1

1/32

3

4

5

6

6

7

7

8

8

10

10

11

13

15

19

27

2

2

2/32

6

8

10

11

12

13

14

15

17

19

21

23

27

31

42

57

3

3

3/32

9

12

15

18

19

21

22

25

27

31

32

36

42

50

65

88

4

4

4/32

12

16

20

24

26

28

30

32

36

40

44

48

55

65

88

118

5

5

5/32

15

21

26

31

32

35

37

42

46

51

55

61

71

84

111

149

6

6

6/32

18

25

31

36

39

42

45

50

55

61

67

72

84

99

134

179

7

7

7/32

21

30

36

43

46

50

52

59

65

72

78

86

99

118

156

210

8

8

8/32

24

33

41

49

52

56

60

67

74

82

90

97

113

134

179

240

9

9

9/32

28

38

47

55

59

64

68

76

84

93

101

111

128

153

202

271

A

10

10/32

31

42

51

61

66

71

75

84

93

103

113

122

141

168

225

301

B

11

11/32

34

47

57

68

72

78

83

93

103

114

124

135

156

187

248

332

C

12

12/32

37

51

62

73

79

85

91

101

113

124

135

147

170

202

271

362

D

13

13/32

40

55

68

80

86

93

98

111

122

135

147

160

185

221

294

393

E

14

14/32

43

59

72

86

93

99

106

118

132

145

158

172

198

237

317

423

F

15

15/32

46

64

78

93

99

107

113

128

141

156

170

185

214

256

340

454

Notes:

(1) The Vmax factor is an approximation.

(2) In case of motion without acceleration (AccShape = 1) the length of the steps = 1/Vmin. In case of accelerated motion (AccShape = 0) the length of the first step is

shorter than 1/Vmin depending of Vmin, Vmax and Acc.

Rev. 4 | Page 11 of 65 | www.onsemi.com