SLLSEK2A June   2014  – March 2017 DRV8846

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 PWM Motor Drivers
      2. 7.3.2 Micro-Stepping Indexer
      3. 7.3.3 Current Regulation
      4. 7.3.4 Decay Mode
      5. 7.3.5 Blanking Time
      6. 7.3.6 Protection Circuits
        1. 7.3.6.1 Overcurrent Protection (OCP)
        2. 7.3.6.2 Thermal Shutdown (TSD)
        3. 7.3.6.3 Undervoltage Lockout (UVLO)
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Stepper Motor Speed
        2. 8.2.2.2 Current Regulation
        3. 8.2.2.3 Decay Modes
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

7.3.2 Micro-Stepping Indexer

To allow a simple step and direction interface to control stepper motors, the DRV8846 contains a microstepping indexer. The indexer controls the state of the H-bridges automatically. When the correct transition is applied at the STEP input, the indexer moves to the next step, according to the direction set by the DIR pin. In 1/8, 1/16, and 1/32 step modes, both the rising and falling edges of the STEP input may be used to advance the indexer, depending on the M0 / M1 setting.

The nENBL pin disables the output stage in indexer mode. When nENBL = 1, the indexer inputs are still active and respond to the STEP and DIR input pins; only the output stage is disabled.

The indexer logic in the DRV8846 allows a number of different stepping configurations. The M0 and M1 pins configure the stepping format (see Table 2).

Table 2. Step Mode Settings

M1 M0 STEP MODE
0 0 Full step (2-phase excitation), rising-edge only
0 Z 1/2 step (1-2 phase excitation), rising-edge only
0 1 1/4 step (W1-2 phase excitation), rising-edge only
Z 0 8 microsteps/step, rising-edge only
Z Z 8 microsteps/step, rising and falling edges
Z 1 16 microsteps/step, rising-edge only
1 0 16 microsteps/step, rising and falling edges
1 Z 32 microsteps/step, rising-edge only
1 1 32 microsteps/step, rising and falling edges

Note that the M0 and M1 pins are tri-level inputs. These pins can be driven logic low, logic high, or high-impedance (Z), like the I0 and I1 pins described previously.

For 1/8, 1/16, and 1/32-step modes, selections are available to advance the indexer only on the rising edge of the STEP input, or on both the rising and falling edges.

The step mode may be changed on-the-fly while the motor is moving. The indexer advances to the next valid state for the new M0 / M1 setting at the next rising edge of STEP.

The home state is 45°. The indexer enters the home state after power-up, after exiting UVLO, or after exiting sleep mode (see the yellow-shaded cells in Table 3 also indicated with a table note).

Table 3 shows the relative current and step directions for different step mode settings. At each rising edge of the STEP input, the indexer travels to the next state in the table. The direction is shown with the DIR pin high; if the DIR pin is low, the sequence is reversed. Positive current is defined as xOUT1 = positive with respect to xOUT2.

Table 3. Relative Current and Step Directions

1/32 STEP 1/16 STEP 1/8 STEP 1/4 STEP 1/2 STEP FULL STEP 70% WINDING CURRENT A WINDING CURRENT B ELECTRICAL ANGLE
1 1 1 1 1 100% 0% 0
2 100% 5% 3
3 2 100% 10% 6
4 99% 15% 8
5 3 2 98% 20% 11
6 97% 24% 14
7 4 96% 29% 17
8 94% 34% 20
9 5 3 2 92% 38% 23
10 90% 43% 25
11 6 88% 47% 28
12 86% 51% 31
13 7 4 83% 56% 34
14 80% 60% 37
15 8 77% 63% 39
16 74% 67% 42
17(1) 9(1) 5(1) 3(1) 2(1) 1(1) 71% 71% 45
18 67% 74% 48
19 10 63% 77% 51
20 60% 80% 53
21 11 6 56% 83% 56
22 51% 86% 59
23 12 47% 88% 62
24 43% 90% 65
25 13 7 4 38% 92% 68
26 34% 94% 70
27 14 29% 96% 73
28 24% 97% 76
29 15 8 20% 98% 79
30 15% 99% 82
31 16 10% 100% 84
32 5% 100% 87
33 17 9 5 3 0% 100% 90
34 –5% 100% 93
35 18 –10% 100% 96
36 –15% 99% 98
37 19 10 –20% 98% 101
38 –24% 97% 104
39 20 –29% 96% 107
40 –34% 94% 110
41 21 11 6 –38% 92% 113
42 –43% 90% 115
43 22 –47% 88% 118
44 –51% 86% 121
45 23 12 –56% 83% 124
46 –60% 80% 127
47 24 –63% 77% 129
48 –67% 74% 132
49 25 13 7 4 2 –71% 71% 135
50 –74% 67% 138
51 26 –77% 63% 141
52 –80% 60% 143
53 27 14 –83% 56% 146
54 –86% 51% 149
55 28 –88% 47% 152
56 –90% 43% 155
57 29 15 8 –92% 38% 158
58 –94% 34% 160
59 30 –96% 29% 163
60 –97% 24% 166
61 31 16 –98% 20% 169
62 –99% 15% 172
63 32 –100% 10% 174
64 –100% 5% 177
65 33 17 9 5 –100% 0% 180
66 –100% –5% 183
67 34 –100% –10% 186
68 –99% –15% 188
69 35 18 –98% –20% 191
70 –97% –24% 194
71 36 –96% –29% 197
72 –94% –34% 200
73 37 19 10 –92% –38% 203
74 –90% –43% 205
75 38 –88% –47% 208
76 –86% –51% 211
77 39 20 –83% –56% 214
78 –80% –60% 217
79 40 –77% –63% 219
80 –74% –67% 222
81 41 21 11 6 3 –71% –71% 225
82 –67% –74% 228
83 42 –63% –77% 231
84 –60% –80% 233
85 43 22 –56% –83% 236
86 –51% –86% 239
87 44 –47% –88% 242
88 –43% –90% 245
89 45 23 12 –38% –92% 248
90 –34% –94% 250
91 46 –29% –96% 253
92 –24% –97% 256
93 47 24 –20% –98% 259
94 –15% –99% 262
95 48 –10% –100% 264
96 –5% –100% 267
97 49 25 13 7 0% –100% 270
98 5% –100% 273
99 50 10% –100% 276
100 15% –99% 278
101 51 26 20% –98% 281
102 24% –97% 284
103 52 29% –96% 287
104 34% –94% 290
105 53 27 14 38% –92% 293
106 43% –90% 295
107 54 47% –88% 298
108 51% –86% 301
109 55 28 56% –83% 304
110 60% –80% 307
111 56 63% –77% 309
112 67% –74% 312
113 57 29 15 8 4 71% –71% 315
114 74% –67% 318
115 58 77% –63% 321
116 80% –60% 323
117 59 30 83% –56% 326
118 86% –51% 329
119 60 88% –47% 332
120 90% –43% 335
121 61 31 16 92% –38% 338
122 94% –34% 340
123 62 96% –29% 343
124 97% –24% 346
125 63 32 98% –20% 349
126 99% –15% 352
127 64 100% –10% 354
128 100% –5% 357
(1) The indexer enters the home state after power-up, after exiting UVLO, or after exiting sleep mode.