The HAL^® 54x family consists of different Hall switches produced in CMOS technology. All sensors include a temperature-compensated Hall plate with active offset compensation, a comparator, and an open-drain output transistor. The comparator compares the actual magnetic flux through the Hall plate (Hall voltage) with the fixed reference values (switching points). Accordingly, the output transistor is switched on or off.

The sensors of this family differ in the switching behavior and the switching points.

In addition to the HAL 50x/51x family, the HAL 54x features a power-on and undervoltage reset.

The active offset compensation leads to constant magnetic characteristics over supply voltage and temperature range. In addition, the magnetic parameters are robust against mechanical stress effects.

The sensors are designed for industrial and automotive applications and operate with supply voltages from 4.3 V to 24 V in the ambient temperature range from –40 °C up to 125 °C.

All sensors are available in the SMD-package SOT89B-1 and in the leaded versions TO92UA-1 and TO92UA-2.

System Architecture

The HAL 54x sensors are monolithic integrated circuits which switch in response to magnetic fields. If a magnetic field with flux lines perpendicular to the sensitive area is applied to the sensor, the biased Hall plate forces a Hall voltage proportional to this field. The Hall voltage is compared with the actual threshold level in the comparator. The temperature-dependent bias increases the supply voltage of the Hall plates and adjusts the switching points to the decreasing induction of magnets at higher temperatures. If the magnetic field exceeds the threshold levels, the open drain output switches to the appropriate state. The built-in hysteresis eliminates oscillation and provides switching behavior of output without bouncing.

HAL 54x block diagram

Main Features

Family Overview

The types differ according to the magnetic flux density values for the magnetic switching points, the temperature behavior of the magnetic switching points.

	Feature	HAL 542	HAL 543	HAL 546	HAL 548
	Switching Behavior	latching	unipolar	unipolar	unipolar
	Sensitivity	high	low	high	medium