New ams position sensors for high-speed electric motors

Austrian sensor manufacturer ams is introducing new position sensors to enhance the electrification of safety-critical vehicle functions such as power steering, active damper control and braking.

The ams AS5147U is a magnetic rotary position sensor chip for use in electric motors that run at speeds up to 28,000 rpm. The new AS5247U is a dual stacked-die version, which provides the redundancy required for ASIL D-rated functional safety applications.

The sensors incorporate new DFS (Dynamic Filter System) technology for position measurements at rotational speeds. The DAEC (Dynamic Angle Error Correction) technology in the sensors enables real-time angle measurement. 

The devices embed a comprehensive set of self-diagnostic features to support automotive manufacturers’ programs for complying with the ISO 26262 functional safety standard. The new AS5x47U sensors also implement a cyclic redundancy check (CRC) protection on communications with external devices.

The company says its position sensors are inherently immune to interference from stray magnetic fields, thanks to their patented differential sensing architecture, and therefore require no shielding.

ams Position Sensors Manager Alexander Rensink said, “The latest position sensor technology from ams helps the industry to accelerate the implementation of electrification through easy-to-use position measurements that maximize torque and efficiency in high-speed motors.”

The AS5x47U products are integrated position measurement solutions incorporating magnetic sensor elements, analog signal conditioning and a DSP-based processing engine. The sensors provide a choice of output formats:

  • ABI incremental outputs (industry standard), now in a higher 14-bit resolution vs 12-bit outputs from earlier versions of the AS5x47 family
  • UVW outputs for implementation in the commutation scheme of a brushless DC (BLDC) motor
  • Digital PWM signals, which can be handled directly by an external microcontroller or microprocessor
  • High-speed standard serial peripheral interface (SPI) now protected by 8-bit CRC

The AS5147U sensor comes in a compact 14-lead TSSOP package. The dual-die AS5247U is equipped with a 7 mm x 7 mm 32-lead TQFP package. Both sensors are qualified to AEC-Q100 Grade 0.

The AS5147U and AS5247U position sensors are available now in production volumes. For more technical information or to request samples, go to and

Source: ams