Fast stray field robust motor position detection

Rutronik is expanding its portfolio of Hall effect sensors with the Micronas HAL 302x family from TDK. The device measures vertical magnetic field components (BZ). Developers can choose between two sensor models (HAL 3020 and HAL 3021) for fast angle determination, with which they can fulfil the need for stray field robust motor position detection and ISO 26262-compliant development. The components in the series have differential or single-ended sine and cosine analog outputs with integrated open-circuit detection. Also, the rotation angle of a solenoid can be calculated by an external A/D converter and an MCU/ECU.

The arrangement of the Hall plates allows the sensors to suppress external magnetic stray fields. Only a simple two-pole magnet in an end-of-shaft configuration is needed to measure the absolute angular position. The magnet can be positioned above or below the sensor. The measuring principle of the Hall plate array can minimise errors due to supply voltage and temperature fluctuations.

An integrated signal path allows the family's non-volatile memory (EEPROM) to be programmed to individually adjust relevant properties such as sine and cosine signal amplification, offset, (absolute) 0-angle, orthogonality, and bandwidth. Programming is carried out via the sensor's output pin, so no extra programming connection is needed.

The family includes integrated diagnostic functions, such as overvoltage and undervoltage detection, as well as wire breakage monitoring during normal operations. The sensor family is ideal for automotive and industrial applications thanks to its extensive certifications and high-temperature capability. The sensors are available in SOIC8 SMD housings.