AMIS30623C623BRG Datasheet, PDF (43/61 Pages) ON Semiconductor – Micro-stepping Motor Driver

AMIS−30623
LIN Lost Before or At Power On
If the LIN communication is lost before or at power on, the
<ActPos> register does not reflect the “real” actual
position. So at LIN – lost a referencing is started using
DualPositioning. A first negative motion for half the
positioner range is initiated until the stall position is reached.
The motion parameters stored in OTP will be used for this.
After this mechanical end position is reached, <ActPos>
will be reset to zero. A second motion will start to the Secure
Position also stored in OTP. More details are given below.
B
FailSafe = 1
No
Yes
First motion of DualPosition
Half the position range
Negative direction
At Stall −> ActPos = ‘0000’
No
SecPos ≠ 0x400
STOP
Yes
Secure Positioning
to SecPos stored in RAM,
copied from OTP
SleepEn = 1
No
Yes
SLEEP
STOP
Figure 25. Case B: LIN Lost at or During Start−Up
If LIN is lost before or at power on, following sequence
will be followed. See Figure 25.
1. If the LIN communication is lost AND
<FailSafe> = 0, secure positioning will be
done at absolute position (stored secure position
<SecPos>.) Depending on SleepEn
AMIS−30623 will enter the <Stop> state or
<Sleep> state. See Table 35.
2. If the LIN communication is lost AND
<FailSafe> = 1 a referencing is started using
DualPositioning, meaning a negative motion for
half the positioner range is initiated until the stall
position is reached. The motion parameters stored
in OTP will be used for this. After this mechanical
end position is reached <ActPos> will be reset to
zero. The direction of the motion is given by the
Shaft bit.
− If <SecPos[10:0]> = 0x400:
No Second Motion will be performed.
− If <SecPos[10:0]> ≠ 0x400:
A second motion to <SecPos> is performed.
The direction is given by <SecPos[10]> in
combination with <Shaft>. Motion is done
with parameters from OTP.
Depending on SleepEn AMIS−30623 will enter the
<Stop> state or <Sleep> state. See Table 35.
Important Remarks:
1. The Secure Position has only a resolution of 9 bit
because only the 9 MSB’s will be copied from
OTP to RAM. See also Secure Position
2. The motion direction to SecPos is given by the
Shaft bit in OTP.
3. In case of HW2 float (= lost LIN address), the
behavior is the same as described above, except
for going to sleep mode. In that case failsafe
operation due to HW2 float is not leading to the
sleep state, otherwise the LIN communication will
wake−up the node and cycling through POR will
occur. See also Hardwired Address HW2.
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