2000 Sep 06 27
Philips Semiconductors
Magnetoresistive sensors for
magnetic field measurement General
The simplest form of temperature compensation is to use
a current source to supply to the sensor instead of a
voltage source. In this case, the resulting reduction in
sensitivitydue to temperature is partially compensated by
a corresponding increase in bridge resistance.
Thusa current source not only improves the stability of the
outputvoltage ‘Vo’, and reduces the variation in sensitivity
to a factor of approximately 1.5 (compared to a factor of
three using the voltage source). However, this method
requires a higher supply voltage, due to the voltage drop
of the current source.
Fig.32 Output voltage ‘Vo’ of a KMZ10B sensor as a function of transverse field ‘Hy’ using a current source, for
several temperatures.
handbook, full pagewidth
0
75 42
MLC135
25
50
50
25
75
2
04
H (kA/m)
y
VO
(mV/V)
T = 25 C
amb o
25 C
o
75 C
o
125 C
o
operating range