Infineon Technologies TLE5012B - Figure 5-23 Increcremental Interface Startup Pulses and First Step Movements at Different Speeds

TLE5012B
Interfaces
User’s Manual 60 Rev. 1.2, 2018-02
Startup pulses
Just after startup, in absolute mode (default mode in the register MOD_4, bits HSM_PLP), the IIF generates the
number of pulses needed to count to the initial angle position on the shortest direction. These pulses may be
generated at the maximum frequency on both IFA and IFB pin (see Table 5-13) and therefore the start up pulses
may take up to 2.1ms to count to an initial angle position of 180° (maximum angular distance). The counting
direction may change once the startup position has been reached (depending on whether the shortest direction
matched the actual rotation direction or not).Changes of angle position from the initial position during the start-up
pulses are tracked.
Figure 5-23 Increcremental Interface startup pulses and first step movements at different speeds
The number of pulses indicates the angle value position. The angle can be calculated counting the numjber of
pulses:
(5.9)
Or measuring the length (in seconds) of the train of pulses:
(5.10)
The actual increment needed to reach a new angle position is updated every update rate time (t
upd
). Depending
on the angle speed, pulses are distributed evenly over the update rate time (t
upd
) up to the maximum increment
frequency specified in Table 5-13.
Figure 5-24 shows an example where the last pulses have a different frequency. If 1000 pulses (~87.9° angle at
startup) have to be transmitted at startup, 1000µs are needed (at maximum frequency). With the default angle
update rate time (t
upd
= 42.7µs), 23.44t
upd
(1000pulses * 1MHz / 42.7µs) are required to transmit the 1000 pulses.
In reality 24t
upd
are used. The first 23t
upd
send 982 pulses at 1MHz (23t
upd
*42.7µs*1Mhz). The remainig 18 pulses
are not send at 1MHz (0.44t
upd
) but at a frequency so that the 18 remaining pulses are distributed over the whole
t
upd
(that is a frequency of 422kHz).
Angle Value is pulsed out at start-up
…
…
Phase B
Phase A
2 steps turned
3 steps turned
(at higher speed than
the previous 2 steps)
90
phase
B-A
90
phase
B-A
12
2
360*#
°
=
pulses
angle
612
10*2
360*(sec)
−
°
=
length
angle