Datasheet

DocID023278 Rev 4 23/75
L6480 Functional description
75
Figure 7. Automatic Full-step switching in Boost mode
6.5 Absolute position counter
An internal 22-bit register (ABS_POS) records all the motor motions according to the
selected step mode; the stored value unit is equal to the selected step mode (full, half,
quarter, etc.). The position range is from -2
21
to +2
21
-1 steps (see Section 9.1.1 on page
44).
6.6 Programmable speed profiles
The user can easily program a customized speed profile defining independently
acceleration, deceleration, maximum and minimum speed values by ACC, DEC,
MAX_SPEED and MIN_SPEED registers respectively (see Section 9.1.5 on page 45, 9.1.6
on page 46, 9.1.7 on page 46 and 9.1.8 on page 46).
When a command is sent to the device, the integrated logic generates the microstep
frequency profile that performs a motor motion compliant to speed profile boundaries.
All acceleration parameters are expressed in step/tick
2
and all speed parameters are
expressed in step/tick; the unit of measurement does not depend on the selected step
mode. Acceleration and deceleration parameters range from 2
-40
to (2
12
-2) 2
-40
step/tick
2
(equivalent to 14.55 to 59590 step/s
2
).
Minimum speed parameter ranges from 0 to (2
12
-
1
) 2
-24
step/tick (equivalent to 0 to 976.3
step/s).
Maximum speed parameter ranges from 2
-18
to (2
10
-1)  2
-18
step/tick (equivalent to 15.25
to 15610 step/s).
Phase A
Phase B
(2N+1) x π /4 (2N+1) x π/4
Full-Step
Microstepping
Microstepping
V
peak
V
peak
AM12850v1