IC-MH16_15 Datasheet, PDF (16/25 Pages) IC-Haus GmbH – 12-BIT ANGULAR HALL ENCODER

iC-MH16
12-BIT ANGULAR HALL ENCODER
the Lissajous curve, enabling the angle information for
the interpolator to be maintained.
preliminary
Rev A1, Page 16/25
V_sin
VOSS
V_sin
GAING
GAINF
α
V_cos
C141107-2
Figure 14: Effect of gain settings GAING and GAINF
α
V_cos
C141107-3
Figure 15: Effect of the sine offset setting
V_sin
VOSC
Deviations of the observed Lissajous curve from the
ideal circle can be corrected by varying the amplitude
offset (register VOSS, VOSC) and amplitude ratio (reg-
ister GCC). Changes in these parameters are described
in the following figures 15 to 17. Each of these settings
has a different effect on the interpolated angle value. A
change in the sine offset thus has a maximum effect
on the angle value at 0 ° and 18 °, with no alterations
whatsoever taking place at angles of 90 ° and 270 °.
When varying the cosine offset exactly the opposite can
be achieved as these angle pairs can be set indepen-
dent of one another. Setting the cosine/sine amplitude
ratio does not change these angles (0 °, 90 °, 180 ° and
270 °); however, in-between values of 45 °, 135 °, 225 °
and 315 ° can still be influenced by this parameter.
α
V_cos
C141107-4
Figure 16: Effect of the cosine offset setting
V_sin
GCC
Once calibration has been carried out a signal such as
the one illustrated in Figure 13 should be available.
In the final stage of the process the amplitude control
can be switched back on (ENAC = 0x1) to enable de-
viations in the signal amplitude caused by variations
in the magnetic field due to changes in distance and
temperature to be automatically controlled.
α
V_cos
C141107-5
Figure 17: Effect of the amplitude ratio