AS5045TR View Datasheet(PDF) - austriamicrosystems AG
Part Name
Description
MFG CO.
'AS5045TR' PDF : 34 Pages View PDF
AS5045
Data Sheet
15 Simulation Modeling
Figure 20. Arrangement of Hall Sensor Array on Chip (principle)
s AG nt still valid With reference to Figure 20, a diametrically magnetized permanent magnet is placed above or below the surface of
e the AS5045. The chip uses an array of Hall sensors to sample the vertical vector of a magnetic field distributed
m t across the device package surface. The area of magnetic sensitivity is a circular locus of 1.1mm radius with respect
to the center of the die. The Hall sensors in the area of magnetic sensitivity are grouped and configured such that
a n orthogonally related components of the magnetic fields are sampled differentially.
o The differential signal Y1-Y2 will give a sine vector of the magnetic field. The differential signal X1-X2 will give an
orthogonally related cosine vector of the magnetic field.
c The angular displacement (Θ) of the magnetic source with reference to the Hall sensor array may then be modelled
l by:
a Θ
=
arctan
(Y 1
(X1
−
−
Y 2)
X 2)
±
0.5°
ic The ±0.5° angular error assumes a magnet optimally aligned over the center of the die and is a result of gain
mismatch errors of the AS5045. Placement tolerances of the die within the package are ±0.235mm in X and Y
n direction, using a reference point of the edge of pin #1 (see Figure 20).
h In order to neglect the influence of external disturbing magnetic fields, a robust differential sampling and ratiometric
calculation algorithm has been implemented. The differential sampling of the sine and cosine vectors removes any
c common mode error due to DC components introduced by the magnetic source itself or external disturbing magnetic
fields. A ratiometric division of the sine and cosine vectors removes the need for an accurate absolute magnitude of
e the magnetic field and thus accurate Z-axis alignment of the magnetic source.
TThe recommended differential input range of the magnetic field strength (B(X1-X2), B(Y1-Y2)) is ±75mT at the surface of
the die. In addition to this range, an additional offset of ±5mT, caused by unwanted external stray fields is allowed.
www.austriamicrosystems.com
Revision 1.7
25 – 33
Share Link: 
