powerSTEP01
Programming manual
11.1.16 TVAL_HOLD, TVAL_RUN, TVAL_ACC and TVAL_DEC
These registers are specific for current mode driving (see Section 9).
The TVAL_HOLD register contains the reference voltage that is assigned to the torque
regulation DAC when the motor is stopped.
The TVAL_RUN register contains the reference voltage that is assigned to the torque
regulation DAC when the motor is running at constant speed.
The TVAL_ACC register contains the reference voltage that is assigned to the torque
regulation DAC during acceleration.
The TVAL_DEC register contains the reference voltage that is assigned to the torque
regulation DAC during deceleration.
The available range is from 7.8 mV to 1 V with a resolution of 7.8 mV, as shown in Table 15.
Table 17. Torque regulation by TVAL_HOLD, TVAL_ACC, TVAL_DEC and TVAL_RUN
registers
TVAL_X [6..0]
Peak reference voltage
0
0
0
0
0
0
0
0
0
0
0
0
0
1
7.8 mV
15.6 mV
1
1
1
1
1
1
1
1
1
1
1
1
0
1
992.2 mV
1 V
11.1.17 T_FAST
This register is specific for current mode driving (see Section 9).
The T_FAST register contains the maximum fast decay time (TOFF_FAST) and the
maximum fall step time (FALL_STEP) used by the current control system (Section 9.2 and
Section 9.3 for details):
Table 18. FS_SPD register
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TOFF_FAST
FAST_STEP
The available range for both parameters is from 2 μs to 32 μs.
Table 19. Maximum fast decay times
TOFF_FAST [3..0] FAST_STEP[3..0] Fast decay time
0
0
0
0
0
0
0
1
2 μs
4 μs
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