JAJSCW8A January 2017 – July 2018 DRV8886
UNLESS OTHERWISE NOTED, this document contains PRODUCTION DATA.
Built-in indexer logic in the DRV8886 device allows a number of different step modes. The M1 and M0 pins are used to configure the step mode as shown in Table 2.
M1 | M0 | STEP MODE |
---|---|---|
0 | 0 | Full step (2-phase excitation) with 71% current |
0 | 1 | 1/16 step |
1 | 0 | 1/2 step |
1 | 1 | 1/4 step |
0 | Z | 1/8 step |
1 | Z | Non-circular 1/2 step |
Table 3 shows the relative current and step directions for full-step through 1/16-step operation. The AOUT current is the sine of the electrical angle and the BOUT current is the cosine of the electrical angle. Positive current is defined as current flowing from the xOUT1 pin to the xOUT2 pin while driving.
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 logic high. If the DIR pin is logic low, the sequence is reversed.
On power-up or when exiting sleep mode, keep the STEP pin logic low, otherwise the indexer advances one step.
NOTE
If the step mode is changed from full, 1/2, 1/4, 1/8, or 1/16 to full, 1/2, 1/4, 1/8, or 1/16 while stepping, the indexer advances to the next valid state for the new step mode setting at the rising edge of STEP. If the step mode is changed from or to noncircular 1/2 step the indexer goes immediately to the valid state for that mode.
The home state is an electrical angle of 45°. This state is entered after power-up, after exiting logic undervoltage lockout, or after exiting sleep mode. Table 3 lists the home state in red.
FULL STEP | 1/2 STEP | 1/4 STEP | 1/8 STEP | 1/16 STEP | ELECTRICAL ANGLE (DEGREES) | AOUT CURRENT (% FULL-SCALE) | BOUT CURRENT (% FULL-SCALE) |
---|---|---|---|---|---|---|---|
1 | 1 | 1 | 1 | 0.000° | 0% | 100% | |
2 | 5.625° | 10% | 100% | ||||
2 | 3 | 11.250° | 20% | 98% | |||
4 | 16.875° | 29% | 96% | ||||
2 | 3 | 5 | 22.500° | 38% | 92% | ||
6 | 28.125° | 47% | 88% | ||||
4 | 7 | 33.750° | 56% | 83% | |||
8 | 39.375° | 63% | 77% | ||||
1 | 2 | 3 | 5 | 9 | 45.000° | 71% | 71% |
10 | 50.625° | 77% | 63% | ||||
6 | 11 | 56.250° | 83% | 56% | |||
12 | 61.875° | 88% | 47% | ||||
4 | 7 | 13 | 67.500° | 92% | 38% | ||
14 | 73.125° | 96% | 29% | ||||
8 | 15 | 78.750° | 98% | 20% | |||
16 | 84.375° | 100% | 10% | ||||
3 | 5 | 9 | 17 | 90.000° | 100% | 0% | |
18 | 95.625° | 100% | –10% | ||||
10 | 19 | 101.250° | 98% | –20% | |||
20 | 106.875° | 96% | –29% | ||||
6 | 11 | 21 | 112.500° | 92% | –38% | ||
22 | 118.125° | 88% | –47% | ||||
12 | 23 | 123.750° | 83% | –56% | |||
24 | 129.375° | 77% | –63% | ||||
2 | 4 | 7 | 13 | 25 | 135.000° | 71% | –71% |
26 | 140.625° | 63% | –77% | ||||
14 | 27 | 146.250° | 56% | –83% | |||
28 | 151.875° | 47% | –88% | ||||
8 | 15 | 29 | 157.500° | 38% | –92% | ||
30 | 163.125° | 29% | –96% | ||||
16 | 31 | 168.750° | 20% | –98% | |||
32 | 174.375° | 10% | –100% | ||||
5 | 9 | 17 | 33 | 180.000° | 0% | –100% | |
34 | 185.625° | –10% | –100% | ||||
18 | 35 | 191.250° | –20% | –98% | |||
36 | 196.875° | –29% | –96% | ||||
10 | 19 | 37 | 202.500° | –38% | –92% | ||
38 | 208.125° | –47% | –88% | ||||
20 | 39 | 213.750° | –56% | –83% | |||
40 | 219.375° | –63% | –77% | ||||
3 | 6 | 11 | 21 | 41 | 225.000° | –71% | –71% |
42 | 230.625° | –77% | –63% | ||||
22 | 43 | 236.250° | –83% | –56% | |||
44 | 241.875° | –88% | –47% | ||||
12 | 23 | 45 | 247.500° | –92% | –38% | ||
46 | 253.125° | –96% | –29% | ||||
24 | 47 | 258.750° | –98% | –20% | |||
48 | 264.375° | –100% | –10% | ||||
7 | 13 | 25 | 49 | 270.000° | –100% | 0% | |
50 | 275.625° | –100% | 10% | ||||
26 | 51 | 281.250° | –98% | 20% | |||
52 | 286.875° | –96% | 29% | ||||
14 | 27 | 53 | 292.500° | –92% | 38% | ||
54 | 298.125° | –88% | 47% | ||||
28 | 55 | 303.750° | –83% | 56% | |||
56 | 309.375° | –77% | 63% | ||||
4 | 8 | 15 | 29 | 57 | 315.000° | –71% | 71% |
58 | 320.625° | –63% | 77% | ||||
30 | 59 | 326.250° | –56% | 83% | |||
60 | 331.875° | –47% | 88% | ||||
16 | 31 | 61 | 337.500° | –38% | 92% | ||
62 | 343.125° | –29% | 96% | ||||
32 | 63 | 348.750° | –20% | 98% | |||
64 | 354.375° | –10% | 100% | ||||
1 | 1 | 1 | 1 | 360.000° | 0% | 100% |
Table 4 shows the noncircular 1/2–step operation. This stepping mode consumes more power than circular 1/2-step operation, but provides a higher torque at high motor rpm.
NON-CIRCULAR 1/2-STEP | AOUT CURRENT
(% FULL-SCALE) |
BOUT CURRENT
(% FULL-SCALE) |
ELECTRICAL ANGLE (DEGREES) |
---|---|---|---|
1 | 0 | 100 | 0 |
2 | 100 | 100 | 45 |
3 | 100 | 0 | 90 |
4 | 100 | –100 | 135 |
5 | 0 | –100 | 180 |
6 | –100 | –100 | 225 |
7 | –100 | 0 | 270 |
8 | –100 | 100 | 315 |