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IC-MZ Datasheet, PDF (6/11 Pages) IC-Haus GmbH – DIFFERENTIAL HALL SWITCH | |||
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iC-MZ
DIFFERENTIAL HALL SWITCH
DEFINITION OF MAGNETIC FIELDS AND SENSOR OUTPUT SIGNALS
Rev A2, Page 6/11
In essence iC-MZ is non-magnetic and thus has prac-
tically no effect on the magnetic ï¬eld to be scanned.
The Hall sensors on the topside of the chip or at pack-
age level (x, y) are sensing the z component Hz of the
magnetic ï¬eld vector at the site of each sensor.
Magnetic ï¬eld component Hz counts as a positive
when the ï¬eld lines emerge on the printed upper side
of the chip.
The source of the magnetic ï¬eld (magnets, coils) can
be placed above or below (back bias) the iC package.
+B
MZ
N
S
In accordance with Figure 2 a distinction can be made
between the different position and polarity of a mag-
net from the sign of the sensor signal. Following the
ampliï¬cation of the Hall voltage difference a differen-
tial analog signal V(A) or V(NA) is available at pins A
and NA with a mean voltage of Vdc (Figure 3).
If âH exceeds a limit of Ht,hi, digital output D switches
to high. If âH undershoots a threshold of Ht,lo, output
D is switched back to low. The switching status com-
plementary to D is available at output ND.
If differential ï¬eld strength âH lies within the Ht,lo..Ht,hi
interval, the momentary switching status of the driver
outputs does not change.
V
MZ+B
N
S
z
y
x
V(A)
Vdc
V(NA)
Figure 1: Example magnet positions in relation to
iC-MZ
0
H
The difference âH between z components H1 and H2
of the magnetic ï¬eld strengths at the site of the two
Hall sensors S1 and S2 is signiï¬cant for the electrical
output signal.
Figure 3: Analog signals A and NA as a function of
the difference in ï¬eld strength âH
âH = H1 â H2
S
N
N
S
V(D)
Ht,hys = Ht,hi â Ht,lo
VB
MH1Z
S1
Pin 1
z
S2
H2
y
x
Pin 1
H>0
MH1Z
S1
S2
H2
H<0
Figure 2: Deï¬nition of the difference in ï¬eld strength
âH
Ht,lo
0
Ht,hi
H
Figure 4: Digital output D in dependence on the dif-
ference in ï¬eld strength âH
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