The HAL^® 1000 is a programmable Hall switch. The major sensor characteristics, the two switching points B_on and B_off, are programmable for the application. The sensor can be programmed to be unipolar or latching, sensitive to the magnetic north pole or sensitive to the south pole, with normal or with an electrically inverted output signal.

The HAL 1000 is based on the HAL 8xx family and features a temperature-compensated Hall plate with choppered offset compensation, an A/D converter, digital signal processing, a push-pull output stage, an EEPROM memory with redundancy and lock function for the calibration data, a serial interface for programming the EEPROM, and protection devices at all pins. Internal digital signal processing is of great benefit because analog offsets, temperature shifts, and mechanical stress effects do not degrade the sensor accuracy.

The HAL 1000 is programmable by modulating the supply voltage. No additional programming pin is needed. Programming is simplified through the use of a 2-point calibration. Calibration is accomplished by adjusting the sensor output directly to the input signal. Individual adjustment of each sensor during the customer’s manufacturing rocess is possible. With this calibration procedure, the tolerances of the sensor, the magnet, and the mechanical positioning can be compensated for the final assembly. This offers a low-cost alternative for all applications that presently require mechanical adjustment or other system calibration.

In addition, the temperature compensation of the Hall IC can be tailored to all common magnetic materials by programming first and second order temperature coefficients of the Hall sensor sensitivity. This enables operation over the full temperature range with constant switching points.

The calculation of the individual sensor characteristics and the programming of the EEPROM memory can easily be done with a PC and the application kit from Micronas.

The sensor is designed and produced in sub-micron CMOS technology for use in hostile industrial and automotive applications with nominal supply voltage of 5 V in the ambient temperature range from - 40 °C up to 150 °C.

The HAL 1000 is available in the leaded packages TO92UT-1 and TO92UT-2.

System Architecture

The Hall plate is sensitive to magnetic north and south polarity. The external magnetic field component perpendicular to the branded side of the package generates a Hall voltage. This voltage is converted to a digital value and processed in the Digital Signal Processing Unit (DSP) according to the settings of the EEPROM registers.

The setting of the LOCK register disables the programming of the EEPROM memory for all time. This register cannot be reset.

As long as the LOCK register is not set, the output characteristic can be adjusted by programming the EEPROM registers. The IC is addressed by modulating the supply voltage. In the supply voltage range from 4.5 V up to 5.5 V, the sensor generates an analog output voltage. After detecting a command, the sensor reads or writes the memory and answers with a digital signal on the output pin. The digital output is switched off during the communication.

Internal temperature compensation circuitry and the choppered offset compensation enables operation over the full temperature range with minimal changes of the switching points. The circuitry also rejects offset shifts due to mechanical stress from the package. The non-volatile memory consists of redundant EEPROM cells. In addition, the HAL 1000 is equipped with devices for overvoltage and reverse-voltage protection at all pins.

HAL 1000 block diagram

Main Features

High-precision Hall switch with programmable switching points and switching behavior

Switching points programmable from - 150 mT up to 150 mT in steps of 0.5% of the magnetic field range

Multiple programmable magnetic characteristics in a non-volatile memory (EEPROM) with redundancy and lock function

Temperature characteristics are programmable for matching all common magnetic materials

Programming through a modulation of the supply voltage

Operates from - 40 °C up to 150 °C ambient temperature

Operates from 4.5 V up to 5.5 V supply voltage in specification and functions up to 8.5 V

Operates with static magnetic fields and dynamic magnetic fields up to 2 kHz

Magnetic characteristics extremely robust against mechanical stress effects

Overvoltage and reverse-voltage protection at all pins

Short-circuit protected push-pull output

EMC and ESD optimized design