|
IC-MH Datasheet, PDF (10/23 Pages) IC-Haus GmbH – 12 BIT ANGULAR HALL ENCODER | |||
|
◁ |
iC-MH
12 BIT ANGULAR HALL ENCODER
Rev B1, Page 10/23
28 27 26 25 24 23 22
1
2
3
4
N 5
6
7
S
21
20
19
18
17
16
15
8 9 10 11 12 13 14
C040907-1
Figure 4: Zero position of the magnet
28 27 26 25 24 23 22
1
2
3
4
N 5
6
7
S
21
20
19
18
17
16
15
8 9 10 11 12 13 14
α=0
+2V
28 27 26 25 24 23 22
(top view)
1
S
21
2
20
3
19
4
18
5
17
6
16
7
N
15
8 9 10 11 12 13 14
α>0
0
VSIN= VPSIN- VNSIN VCOS= VPCOS- VNCOS
-90°
90°
180° 270° 360°
-2V
α
C041007-3
Figure 5: Pattern of the analog sensor signals with
the angle of rotation
Hall Signal Processing
The iC-MH module has a signal calibration function
that can compensate for the signal and adjustment
errors. The Hall signals are ampliï¬ed in two steps.
First, the range of the ï¬eld strength within which the
Hall sensor is operated must be roughly selected. The
ï¬rst ampliï¬er stage can be programmed in the follow-
ing ranges:
GAING(1:0)
Adr 0x00; Bit 7:6
00
5-fold
01
10-fold
01
15-fold
01
20-fold
Table 6: Range selection for Hall signal ampliï¬cation
used. With the amplitude control (ENAC = â1â) acti-
vated, the GAINF register bits have no effect.
GCC(6:0)
0x00
0x01
...
0x3F
0x40
...
0x7F
Adr 0x01; Bit 6:0
1,000
1,0015
exp(
ln(20)
2048
·
GCC)
1,0965
0,9106
exp(â
ln(20)
2048
·
(128
â
GCC))
0,9985
Table 8: Ampliï¬cation calibration cosine
The operating range can be speciï¬ed in advance in
accordance with the temperature coefï¬cient and the
magnet distance. The integrated amplitude control can
correct the signal amplitude between 1 and 20 via an-
other ampliï¬cation factor. Should the control reach the
range limits, a different signal ampliï¬cation must be se-
lected via GAING.
GAINF(5:0)
Adr 0x00; Bit 5:0
0x00
1,000
0x01
...
0x3F
1,048
exp(
ln(20)
64
·
GAINF
)
19,08
The GCC register is used to correct the sensitivity of
the sine channel in relation to the cosine channel. The
cosine amplitude can be corrected within a range of
approximately ±10%.
ENAC
0
1
Adr 0x01; Bit 7
amplitude control deactivated
amplitude control active
Table 9: Activation of amplitude control
Table 7: Hall signal ampliï¬cation
The second ampliï¬er stage can be varied in an addi-
tional range. With the amplitude control (ENAC = â0â)
deactivated, the ampliï¬cation in the GAINF register is
The integrated amplitude control can be activated with
the ENAC bit. In this case the differential signal am-
plitude is adjusted to 4 Vss and the values of GAINF
have no effect here.
|
▷ |