Philips Semiconductors
Magnetoresistive sensors for
magnetic field measurement
General
Figure 10 is similar to Fig.9, but with the sensor powered by a constant current supply. Figure 10 shows that, in this case, the temperature dependency of sensitivity is significantly reduced. This is a direct result of the increase in bridge resistance with temperature (see Fig.8), which
partly compensates the fall in sensitivity by increasing the voltage across the bridge and hence the output voltage. Figure 8 demonstrates therefore the advantage of operating with constant current.
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| H y (kA/m) | ||
Fig.10 Output voltage ‘Vo’ of a KMZ10B sensor as a function of transverse field ‘Hy’ for several temperatures.
2000 Sep 06 | 9 |
