New Industry Products

3D Position Hall Sensor with Stray-Field Compensation and SPI Interface

October 09, 2019 by Paul Shepard

TDK Corporation has expanded its Micronas position sensor portfolio with a new member of the previously announced masterHAL® sensor family HAL® 39xy. The new HAL 3900 features real 3D magnetic-field measurement capability and 2D stray-field robust position detection. Measurement data is delivered via a high-speed SPI interface.

The sensors meet today's and tomorrow's automotive and industrial market needs and offer four different measurement modes in a single device: Linear position detection, rotary 360° angle detection and rotary 180° angle detection with stray field compensation including gradient fields as well as the capability for real 3D magnetic field measurement (BX, BY, BZ). Samples are already available. Start of production is planned for second quarter 2020.

Main applications

  • Selectors and gear shifters
  • Position detection in transmission systems
  • Steering-angle detection
  • All kinds of actuators with embedded microcontroller

The heart of the HAL 3900 sensor is the patented 3D HAL® pixel cell technology. It not only helps to measure magnetic fields very accurately, but also enables the measurement of all three magnetic-field components at one single spot. By measuring the BX, BY and BZ components, the sensor is able to detect the direction of the magnetic field.

At the same time, the unique concept of an array of Hall plates offers a 2D stray-field compensation. The highly flexible sensor array of the HAL 3900 sensor helps design engineers to select the best operation mode for any given measurement task. The HAL 3900 is the only solution available on the market that integrates all four modes in a single device.

The combination of SPI interface and 3D capability makes the HAL 3900 a perfect solution for applications like gear shifters or steering column switches. The unique stray-field concept makes the sensor fit for applications requiring a stray-field robust off-axis measurement. The angular error due to stray fields can be reduced to less than 0.3° in the presence of a stray field of 4000A/m.

HAL 3900 also features a sleep mode helping customers to reduce the average current consumption that is increasingly important for electric cars. The device is developed as an ASIL B ready SEooC (Safety Element out of Context) according to ISO 26262.

Main features and benefits

  • Real 3D magnetic-field measurement of BX, BY and BZ
  • SPI interface
  • Sleep mode to reduce average current consumption
  • Transmission of temperature-compensated magnetic raw values (BX, BY, BZ), up to two calculated angles, magnetic-field amplitude and/or chip temperature
  • Stray-field robust position detection (linear and rotary up to 360°) covering ISO 11452-8 requirements
  • Compensation of stray fields with gradients for applications with 180° rotation
  • SEooC according to ISO 26262 to support functional-safety applications
  • Suitable for automotive applications, thanks to a wide ambient temperature range from -40°C up to 160°C