STMicroelectronics Fully integrated stepper motor driver mounting the L6472 in a high power PowerSO package EVAL6472PD EVAL6472PD Datenbogen

Produktcode

EVAL6472PD

Programming manual

L6472

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DocID022729 Rev 3

expressed in step/tick (format unsigned fixed point 0.18) and to convert it in step/s the
following formula can be used.

Equation 6

If the FS_SPD value is set to h3FF (max.) the system always works in microstepping mode
(SPEED must go beyond the threshold to switch to full-step mode). Setting FS_SPD to zero
does not have the same effect as setting step mode to full-step two phase on: the zero
FS_SPD value is equivalent to a speed threshold of about 7.63 step/s.

The available range is from 7.63 to 15625 step/s with a resolution of 15.25 step/s.

9.1.10

TVAL_HOLD, TVAL_RUN, TVAL_ACC and TVAL_DEC

The TVAL_HOLD register contains the current value that is assigned to the torque
regulation DAC when the motor is stopped.

The TVAL_RUN register contains the current value that is assigned to the torque regulation
DAC when the motor is running at constant speed.

The TVAL_ACC register contains the current value that is assigned to the torque regulation
DAC during acceleration.

The TVAL_DEC register contains the current value that is assigned to the torque regulation
DAC during deceleration.

The available range is from 31.25 mA to 4 A with a resolution of 31.25 mA, as shown in

Table 12

step s







FSSPD 0.5



 2

–



tick

--------------------------------------------------------

Table 12. Torque regulation by TVAL_HOLD, TVAL_ACC, TVAL_DEC and TVAL_RUN

registers

TVAL_X [6 … 0]

Output current amplitude

0 0 0 0 0 0 0

31.25

0 0 0 0 0 0 1

62.5

…

1 1 1 1 1 1 0

3.969

1 1 1 1 1 1 1