Hall sensor and method of operating a Hall sensor

摘要

A Hall sensor comprises a Hall element (1; 30; 31; 60) and an amplifier (2; 32; 33). The Hall element is placed inside the amplifier so that the current flowing through the Hall element also flows through the transistors of an amplifier stage of the amplifier. The current flowing through the Hall element flows for example through the transistors of an input stage of the amplifier. In doing so the current consumption of the Hall sensor is reduced to the current the amplifier consumes itself. The Hall sensor is preferably operated in a modified spinning current that preserves the correlation of the noise as far as possible. Preferably, the current flowing through the Hall element is pulsed. This mode of operation is useful for applications based on a battery as power supply. The signal to noise ratio related to the power consumption increases. A pulsed operation means that the current flowing through the Hall element is switched on and off with a predetermined frequency.