Note:
- For all types of reference profiles, a zero input
reference (0-V in analog mode, 0% duty in PWM
mode, DIGITAL_SPEED_CTRL = 0b I2C mode
or 0-Hz in frequency mode) stops the motor
irrespective of the reference profile
configuration.
- The reference value in Figure 6-20,
Figure 6-21 and Figure 6-22 is decided by control mode (SPEED_LOOP_DIS) as follows,
- Speed control mode (SPEED_LOOP_DIS
= 0b): SPEED_REF (Hz) = (REF_x/255) x MAX_SPEED (Hz)
- Current control mode
(SPEED_LOOP_DIS = 1b): CURRENT_REF (A) = (REF_x/255) x ILIMIT (A)
Linear reference profiles can be configured by
setting REF_PROFILE_CONFIG to 01b. Linear profiles
feature input references (SPEED_REF or
CURRENT_REF) which change linearly between
REF_CLAMP1 and REF_CLAMP2 with different slopes
which can be set by configuring DUTY_x and
REF_x.
- DUTY_OFF1 configures the duty command below which
the reference will be REF_OFF1.
- DUTY_OFF1 and DUTY_ON1
configure a hysteresis between reference levels, REF_CLAMP1 and REF_OFF1 as shown in
Figure 6-20.
- DUTY_CLAMP1 configures the
duty command till which reference will be constant
with a value REF_CLAMP1. DUTY_CLAMP1 can be placed
anywhere between DUTY_ON1 and DUTY_A.
- DUTY_A configures the duty
command for reference REF_A. The reference changes from REF_CLAMP1 to REF_A linearly
between DUTY_CLAMP1 and DUTY_A. DUTY_A to DUTY_E has to be in the same order as shown in
Figure 6-20.
- DUTY_B configures the duty
command for reference REF_B. The reference changes
linearly between DUTY_A and DUTY_B.
- DUTY_C configures the duty
command for reference REF_C. The reference changes
linearly between DUTY_B and DUTY_C.
- DUTY_D configures the duty
command for reference REF_D. The reference changes
linearly between DUTY_C and DUTY_D.
- DUTY_E configures the duty
command for reference REF_E. The reference changes
linearly between DUTY_D and DUTY_E.
- DUTY_CLAMP2 configures the
duty command above which the reference will be
constant at REF_CLAMP2. REF_CLAMP2 configures this
constant reference between DUTY_CLAMP2 and
DUTY_OFF2 . The reference changes linearly between
DUTY_E and DUTY_CLAMP2. DUTY_CLAMP2 can be placed
anywhere between DUTY_E and DUTY_ON2.
- DUTY_OFF2 and DUTY_ON2 configure a hysteresis between reference levels REF_CLAMP2 and
REF_OFF2 as shown in Figure 6-20.
- DUTY_OFF2 configures the
duty command above which the reference will change
from REF_CLAMP2 to REF_OFF2.