IC-MU150 Datasheet, PDF (20/64 Pages) IC-Haus GmbH – MAGNETIC OFF-AXIS POSITION ENCODER - POLE WIDTH 1.50MM

iC-MU150 MAGNETIC OFF-AXIS
POSITION ENCODER - POLE WIDTH 1.50MM
ENAC
Code
0
1
Addr. 0x05; bit 7
Description
Amplitude control not active (constant)
Amplitude control active (sin² + cos²)
Table 18: Amplitude control unit activation
Rev B1, Page 20/64
Offset compensation
If there is an offset in the sine or cosine signal, possibly
caused by a magnet not being precisely adjusted, for
instance, this can be corrected by registers VOSS_x
and VOSC_x. The output voltage can be shifted in each
case by ±63 mV in order to compensate for the offset.
The current gain set by the amplitude control unit can be
read with the parameters ACGAIN_M and ACGAIN_N
for the gain range, AFGAIN_M and AFGAIN_N for the
gain factor (ref. Table 19 and 20). AFGAIN_M and AF-
GAIN_N shows coarse steps of the gain factor, but the
amplitude control unit uses a finer resolution to control
the gain factor.
ACGAIN_M(1:0)
Addr. SER:0x2B; bit 4:3
R
ACGAIN_N(1:0)
Addr. SER:0x2F; bit 4:3
R
Code
Gain range
0x0
4.4
0x1
7.8
0x2
12.4
0x3
20.7
VOSS_M(6:0)
Addr. 0x02; bit 6:0
VOSS_N(6:0)
Addr. 0x08; bit 6:0
VOSC_M(6:0)
Addr. 0x03; bit 6:0
VOSC_N(6:0)
Addr. 0x09; bit 6:0
Code
Description
0x00
0 mV
0x01
1 mV
...
...
0x3F
63 mV
0x40
0 mV
0x41
-1 mV
...
...
0x7F
-63 mV
Table 21: Sine and cosine offset adjustment
Table 19: Current gain range of amplitude control unit
AFGAIN_M(2:0)
Addr. SER:0x2B; bit 2:0
R
AFGAIN_N(2:0)
Addr. SER:0x2F; bit 2:0
R
Code
Description
0x0
1.00
0x1
1.45
...
exp(
ln(20)
8
·
AFGAIN_x)
0x7
13.75
Table 20: Current gain factor of amplitude control unit
After startup the gain is increased until the set amplitude
is obtained. If the input amplitude is altered by the dis-
tance between the magnet and sensor being varied, or
if there is a change in the supply voltage or temperature,
the gain is automatically adjusted. The conversion of
the sine signals into high-resolution quadrature signals
thus always takes place at optimum amplitude.
PSIN_x
PCOS_x
SIN
DIG
PSx
PCx
PSIN 500mV/DIV 100µs/DIV
PCOS 500mV/DIV
PSM 200mV/DIV 100µs/DIV
PCM 200mV/DIV
Phase adjustment
The phase between sine and cosine is adjusted by
PHR_x and PH_x (6:0). The compensation range for
the master track is with range selector PHR_M = 0 ap-
prox. ±8° and in extended phase adjustment range
PHR_M=1 ±16°. The compensation range for the
nonius track is approx. ±12° (PHR_N=0) and ±20°
(PHR_N=1), respectively.
PHR_M
PH_M(6:0)
PH_M(6:0)
0x00
...
0x3F
0x40
...
0x7F
Addr. 0x04; bit 7
Addr. 0x04; bit 6:0
PHR_M=0
PHR_M=1
0°
0°
+8° * PH_M/63
+16° * PH_M/63
+8°
+16°
0°
0°
-8° * (PH_M-64)/63
-16° * (PH_M-64)/63
-8°
-16°
Table 22: Master track phase adjustment
PHR_N
PH_N(6:0)
PH_N(6:0)
0x00
...
0x3F
0x40
...
0x7F
Addr. 0x0A; bit 7
Addr. 0x0A; bit 6:0
PHR_N=0
PHR_N=1
0°
0°
+12° * PH_N/63
+20° * PH_N/63
+12°
+20°
0°
0°
-12° * (PH_N-64)/63
-20° * (PH_N-64)/63
-12°
-20°
2Vpp
0.5Vpp
Table 23: Nonius track phase adjustment
Figure 12: Definition of peak-peak amplitude