Datasheet

TMC2130 DATASHEET (Rev. 1.09 / 2017-MAY-15) 37
www.trinamic.com
5.5.4 PWMCONF – Voltage PWM Mode stealthChop
0X70: PWMCONF – VOLTAGE MODE PWM STEALTHCHOP
Bit
Name
Function
Comment
…
-
reserved
set to 0
21
freewheel1
Allows different
standstill modes
Stand still option when motor current setting is zero
(I_HOLD=0).
%00: Normal operation
%01: Freewheeling
%10: Coil shorted using LS drivers
%11: Coil shorted using HS drivers
20
freewheel0
19
pwm_
symmetric
Force symmetric PWM
0
The PWM value may change within each PWM cycle
(standard mode)
1
A symmetric PWM cycle is enforced
18
pwm_
autoscale
PWM automatic
amplitude scaling
0
User defined PWM amplitude. The current settings
have no influence.
1
Enable automatic current control
Attention: When using a user defined sine wave
table, the amplitude of this sine wave table should
not be less than 244. Best results are obtained with
247 to 252 as peak values.
17
pwm_freq1
PWM frequency
selection
%00: f
PWM
=2/1024 f
CLK
%01: f
PWM
=2/683 f
CLK
%10: f
PWM
=2/512 f
CLK
%11: f
PWM
=2/410 f
CLK
16
pwm_freq0
15
PWM_
GRAD
User defined amplitude
(gradient)
or regulation loop
gradient
pwm_
autoscale=0
Velocity dependent gradient for PWM
amplitude:
PWM_GRAD * 256 / TSTEP
is added to PWM_AMPL
14
13
12
11
pwm_
autoscale=1
User defined maximum PWM amplitude
change per half wave (1 to 15)
10
9
8
7
PWM_
AMPL
User defined amplitude
(offset)
pwm_
autoscale=0
User defined PWM amplitude offset (0-255)
The resulting amplitude (limited to 0…255)
is:
PWM_AMPL + PWM_GRAD * 256 / TSTEP
6
5
4
3
pwm_
autoscale=1
User defined maximum PWM amplitude
when switching back from current chopper
mode to voltage PWM mode (switch over
velocity defined by TPWMTHRS). Do not set
too low values, as the regulation cannot
measure the current when the actual PWM
value goes below a setting specific value.
Settings above 0x40 recommended.
2
1
0