Stray-Field Robust 3D Position Sensors with Digital Output Interfaces

HAL 39xy is a high-end 3D position sensor family from TDK-Micronas, developed for stray-field robust linear and angular position sensing and ISO 26262–compliant development. The family includes various members; all devices measure a full 360° angular range as well as linear movements. Selected models (HAL/R 3900 and HAL/C/R 393x) support optional 3D position detection. Depending on the variant, sensors can transmit temperature compensated magnetic field components (B_X, B_Y, B_Z) or up to two calculated angles; the HAL 3980 can additionally transmit angular speed. Setpoint linearization is available as either 33 equidistant setpoints or 17 variable setpoints.

Measurement is based on TDK-Micronas’ 3D HAL technology. An array of Hall plates suppresses external magnetic stray fields, so rotation measurement normally requires only a simple two-pole magnet; off-axis measurements are also possible. Depending on the device variant, outputs include temperature compensated field components, calculated angles and - for specific models - angular speed.

The sensors are defined as SEooC (Safety Element out of Context) ASIL B/C ready according to ISO 26262; dual-die variants can be integrated in automotive safety related systems up to ASIL D. Key parameters such as gain, offset and reference position can be adjusted to the magnetic circuitry by programming the nonvolatile memory. Devices are specified for operation in an ambient temperature range of −40 °C to +150 °C. HAL 39xy devices are available in a very small eight-pin SOIC8 package. HAC 39xy devices come in a 3-pin leaded TO92UF package that integrates up to two capacitors together with the sensor chip; with these capacitors HAC 39xy meets stringent system level ESD and EMC requirements and can eliminate the need for a PCB, reducing system size and cost. HAR 39xy devices are offered in a small sixteen-pin SSOP16 package with full redundancy; each sensor contains two independent dies placed upon each other, mechanically separated and electrically insulated, so both dies measure almost the same magnetic field and provide synchronous outputs. The devices’ high sensitivity combined with low angular error allows system designers to use cost efficient ferrite magnets.
 

HAL 39xy Family Overview

HAL / HAR 3900:

• SPI
• Up to two angles or values of B_X, B_Y, and B_Z
• Low-power mode with wake-up by magnetic field
• Position information change / wake-up pin
• 16-bit data with CRC and rolling counter
• 5 MHz SPI

HAL / HAC / HAR 3930:

• PWM/SENT/ Switch
• Up to two angles
• Push-pull or open-drain output
• Programmable switching levels (HAL 3930 / HAR 3930 only)
• ASIL B and ASIL C ready versions available

HAL / HAR 3935:

• PWM/SENT/ Switch
• Up to two angles
• Push-pull or open-drain output
• Programmable switching levels
• Low-power mode to avoid the need for external low-power Hall effect switches for applications like brake pedals

HAL 3960:

• PWM
• One angle
• 2-wire PWM

HAL 3970:

• SPC (Short PWM Code)
• One angle and temperature
• Secure rolling counter
• Enhanced 12-bit serial message

HAL / HAC 3980:

• PSI5 rev. 2.2
• One angle and angular speed,
• PSI5 rev. 2.x and support of frames of rev. 1.3
• Asynchronous mode / synchronous parallel and universal bus mode / variable time-triggered bus mode

HAL / HAR 3927:

• Ratiometric analog output / SENT interface
• One angle

License Note:
HAL 39xy, HAC 39xy, and HAR 39xy use licenses of Fraunhofer Institute for Integrated Circuits IIS.