This paper provides a comparison between GMR multilayer and spin-valve sens
ors used for magnetic field sensing applications. Both types of sensor cons
idered use a bridge configuration to reduce the effect of thermal drift and
are biased to optimize sensitivity and linearity. In comparing the perform
ance of these devices a simple model has been used which has been shown to
predict the sensor performance to better that 5% over a wide range of input
parameters.
It is shown that although spin-valve sensors have a slightly higher sensiti
vity, linearity, and better signal to noise ratio than GMR multilayer devic
es, they have a slightly reduced dynamic range and a vastly inferior vector
performance. This limits their applications to areas where good vector res
ponse is not of importance.