The HAL 411 is a Linear Hall-effect sensor produced in CMOS technology. The sensor includes a temperature-compensated Hall plate with choppered offset compensation, two linear output stages, and protection devices.

The output voltage is proportional to the magnetic flux density through the Hall plate. The choppered offset compensation leads to stable magnetic characteristics over supply voltage and temperature.

The HAL 411 can be used for magnetic field measurements, current measurements, and detection of any mechanical movement. Very accurate angle measurements or distance measurements can also be done. The sensor is very robust and can be used in electrically and mechanically hostile environments.

The sensor is designed for industrial and automotive applications and operates in the ambient temperature range from –40 °C up to 100 °C and is available in the SMD-package SOT-89B.

System Architecture

The differential output voltage consists of two components due to the switching offset compensation technique.

The average of the differential output voltage represents the magnetic flux density. This component is overlaid by a differential AC signal at a typical frequency of 147 kHz. The AC signal represents the internal offset voltages of amplifiers and hall plates that are influenced by mechanical stress and temperature cycling.

External filtering or integrating measurement can be done to eliminate the AC component of the signal. As a result, the influence of mechanical stress and temperature cycling is suppressed. No adjustment of magnetic offset is needed.

The sensitivity is stabilized over a wide range of temperature and supply voltage due to internal voltage regulation and circuits for temperature compensation.

Block diagram of the HAL 411

Main Features