Accurate rotation sensing in harsh and noisy environments

Featured for accurate angular measurement in harsh environments, the austriamicrosystems AS5145 magnetic rotary encoder has two digital 12-bit outputs as well as an incremental quadrature output optimised for high noise immunity.

The AS5145 is a contactless sensor delivered as a system-on-chip, performing rotation sensing throughout 360° with 4096-positions resolution. With on-chip sigma-delta conversion and DSP, the device produces absolute position data as either a serial output or PWM signal.

A simple two-pole magnet, rotating over the centre of the chip, is used to measure the angle. The magnet may be placed above or below the IC. By implementing a differential-measurement technique, as well as Hall-sensor conditioning circuitry, the AS5145 is able to operate accurately in the presence of stray magnetic fields or if the magnet becomes mis-aligned. The AS5145 is also stable over a wide temperature range. Accuracy is within ±0.5º at room temperature and remains within ±0.9º up to the maximum specified temperature of 150°C, where noise is greatest.

As well as its high accuracy and stability, the AS5145 simplifies system integration by offering special modes such as daisy-chain mode, which allows reading of multiple sensors connected to the serial bus. There is also a sync mode, which allows external electronics to synchronise with the AS5145 using data-ready signals at the device’s two dedicated Test-output pins.

 

FEATURES Internal voltage regulator User-programmable zero position Failure-detection mode Magnet-placement indicator Fully qualified to AEC-Q100

APPLICATIONS Automotive steering and transmission controls Headlamp positioning Industrial robotics Replacement of high-end potentiometers Low-jitter incremental encoders

 

 

 

 

The AS5145 demo board is available to members of the Future Board Club. To apply for the development board, and membership of the Board Club, go to www.my-boardclub.com/manf-offers.htm This offer is free and subject to qualification.

 

austriamicrosystems / AS5145