Datasheet

Programming manual L6480

48/75 DocID023278 Rev 4

9.1.11 INT_SPEED

The INT_SPEED register contains the speed value at which the BEMF compensation curve

changes slope (Section 7.4 on page 38 for details). Its value is expressed in step/tick and to

convert it in [step/s] the following formula can be used:

Equation 10

where INT_SPEED is the integer number stored in the register and tick is 250 ns.

The available range is from 0 to 976.5 step/s with a resolution of 0.0596 step/s.

Any attempt to write the register when the motor is running causes the command to be

ignored and the NOTPERF_CMD flag to rise (Section 9.1.24 on page 59).

9.1.12 ST_SLP

The ST_SLP register contains the BEMF compensation curve slope that is used when the

speed is lower than the intersect speed (Section 7.4 on page 38). Its value is expressed in

s/step and the available range is from 0 to 0.004 with a resolution of 0.000015.

When ST_SLP, FN_SLP_ACC and FN_SLP_DEC parameters are set to zero, no BEMF

compensation is performed.

Any attempt to write the register when the motor is running causes the command to be

ignored and the NOTPERF_CMD flag to rise (Section 9.1.24 on page 59).

9.1.13 FN_SLP_ACC

The FN_SLP_ACC register contains the BEMF compensation curve slope that is used when

the speed is greater than the intersect speed during acceleration (Section 7.4 on page 38

for details). Its value is expressed in s/step and the available range is from 0 to 0.004 with

a resolution of 0.000015.

When ST_SLP, FN_SLP_ACC and FN_SLP_DEC parameters are set to zero, no BEMF

compensation is performed.

Any attempt to write the register when the motor is running causes the command to be

ignored and the NOTPERF_CMD flag to rise (Section 9.1.24 on page 59).

Table 15. Voltage amplitude regulation registers

KVAL_X [7…0] Output voltage

00000000 0

00000001 V

x (1/256)

…

11111110 V

x (254/256)

11111111 V

x (255/256)

step/s

INT_SPEED 2

18–



tick

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