Overview: MICRONAS HAL300 Differential Hall Effect Sensor IC Edition July 15, 1998 6251-345-1DS MICRONAS HAL300 Differential Hall Effect Sensor IC in CMOS technology
Introduction
The HAL 300 is a differential Hall switch produced in CMOS technology. The sensor includes 2 temperaturecompensated Hall plates (2.05 mm apart) with active offset compensation, a differential amplifier with a Schmitt trigger, and an open-drain output transistor (see Fig. 2).
The HAL 300 is a differential sensor which responds to spatial differences of the magnetic field. The Hall voltages at the two Hall plates, S1 and S2, are amplified with a differential amplifier. The differential signal is compared with the actual switching level of the internal Schmitt trigger. Accordingly, the output transistor is switched on or off.
The sensor has a bipolar switching behavior and requires positive and negative values of ∆B = BS1 – BS2 for correct operation.
The HAL 300 is an ideal sensor for applications with a rotating multi-pole-ring in front of the branded side of the package (see Fig. 4 and Fig. 5), such as ignition timing, anti-lock brake systems, and revolution counting.
For applications in which a magnet is mounted on the back side of the package (back-biased applications), the HAL320 is recommended.
The active offset compensation leads to constant magnetic characteristics over supply voltage and temperature.
The sensor is designed for industrial and automotive applications and operates with supply voltages from 4.5 V to 24 V in the ambient temperature range from –40 °C up to 150 °C.
The HAL 300 is available in a SMD-package (SOT-89A) and in a leaded version (TO-92UA).
