Abstract
In this work, we first compare the different characteristics between the voltage mode and current mode Hall effect devices. And applying the theory to obtain the best device’s geometry dimensions in the EPISIL 1.5μm-25V Bipolar process. Then choose the current mode Hall effect device to be the core of the integrated circuit, and transform the device’s output current signal to voltage signal with a transimpedance amplifier. This current mode system has wider frequency band than the voltage mode Hall effect device. High temperature environment will damage the Hall device’s signal substantially and it is necessary to use an automatic gain control circuit to compensate the loss of the signal. A low-gain amplifier is connected to the output of the transimpedance amplifier to make the signal swing in the acceptable range. For the change of the DC biasing point with large temperature variation, we use the level shifting circuit to correct these and get the best condition.