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AS5132

Datasheet - Detailed Descri p ti on

7.3.2 Step Output Mode

Step Output mode provides a specific combination of the A incremental signal and the index signal I. The number of pulse can be configured with

the input pattern of the test input pins.

Figure 17. Step Mode of the AS5132 with Different Number of Pulses

7.3.3 Pre-Commutation Function

This feature can be used to optimize the torque characteristic at a certain speed of the BLDC motor. The output signals U, V and W can be

shifted by a specific number of degrees back and forward. The AS5132 distinguish between the static and dynamic pre commutation value. The

static value is similar to an additional zero programming and can be programmed only once. The dynamic value is stored in the interface register

and can be changed during operation.

The pin DIR defines if the value of pre-commutation is added or subtracted. The dynamic commutation register will be set to zero after a rotation

change indicated by the external pin DIR. Due to internal synchronization, the outputs U,V,W will change 3 internal clock cycles after the change

of DIR input signal.

Table 7. Definition of the Pre-Commutation Direction

DIR

Rotation

Consequence

0

Clock wise

PRE_COM values added to absolute angle

1

Counter clock wise

PRE_COM values subtracted from absolute angle

Absolute position

STEP

180

12

12

3

179

178

177

176

175

6

5

4

Absolute position

STEP

12

34

90

89

88

87

12

56

7

Absolute position

STEP

12

60

59

3

58

12

4

5

Absolute position

STEP

12

24

3

1

2