The HAL^® 526 is a Hall switch produced in CMOS technology. The sensor includes 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 active offset compensation leads to magnetic parameters which are robust against mechanical stress effects. In addition, the magnetic characteristics are constant in the full supply voltage and temperature range.

The sensor is designed for industrial and automotive applications and operates with supply voltages from 3.8 V to 24 V in the ambient temperature range from −40 °C up to 125 °C.

The HAL 526 is available in the SMD-package SOT89B-1 and in the leaded versions TO92UA-1 and TO92UA-2.

System Architecture

Magnetic offset caused by mechanical stress is compensated for by using the “switching offset compensation technique”. Therefore, an internal oscillator provides a two phase clock. The Hall voltage is sampled at the end of the first phase. At the end of the second phase, both sampled and actual Hall voltages are averaged and compared with the actual switching point. Subsequently, the open drain output switches to the appropriate state. The time from crossing the magnetic switching level to switching of output can vary between zero and 1/f_osc.

HAL 526 block diagram

Main Features

Operates from 3.8 V to 24 V supply voltage

Operates with static magnetic fields and dynamic magnetic fields up to 10 kHz

Switching behavior: latching

Typical temperature coefficient: −2000 ppm/K

Overvoltage protection at all pins

Reverse-voltage protection at VDD-pin

Magnetic characteristics are robust against mechanical stress effects

Short-circuit protected open-drain output by thermal shut down

Constant switching points over a wide supply voltage range

The decrease of magnetic flux density caused by rising temperature in the sensor system is compensated by a built-in negative temperature coefficient of the magnetic characteristics

Ideal sensor for window lifter, ignition timing, and revolution counting in extreme automotive and industrial environments

EMC corresponding to DIN 40839