ZHCSER7C October 2015 – November 2018 DRV8885
PRODUCTION DATA.
Built-in indexer logic in the DRV8885 allows a number of different stepping configurations. The Mx pins are used to configure the stepping format 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; BOUT current is the cosine of the electrical angle. Positive current is defined as current flowing from xOUT1 to xOUT2 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 will advance one step.
Note that if the step mode is changed from full, ½, ¼, 1/8, or 1/16 to full, ½, ¼, 1/8, or 1/16 while stepping, the indexer will advance to the next valid state for the new MODE setting at the rising edge of STEP. If the step mode is changed from or to non-circular ½ step the indexer will go 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. This is shown in the table below with cells outlined 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% |
Non-circular 1/2–step operation is shown below. This stepping mode consumes more power than circular ½-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 |