MagAlpha Contactless Angle Sensors

Monolithic Power Systems’ MA302, MA702, and MA730 sensors detect the absolute angular position of a diametrically-magnetized cylinder on a rotating shaft. Fast data acquisition and processing provide accurate angle measurement at speeds from 0 rpm to 60,000 rpm. These angle sensors support a wide range of spatial configurations and magnetic field strengths. Both off-axis (side-shaft mounting) and end-of-shaft configurations are supported. The sensors feature magnetic field strength detection with programmable thresholds to allow sensing of the magnet position relative to the sensor for functions such as sensing axial movements or for diagnostics.

The MA800 is an easy-to-use magnetic angle encoder with a digital output designed to replace analogic potentiometers or rotary switches. This encoder is designed for slow operation such as human-machine interface (HMI) or manual controls where the rotating speed remains below 200 rpm. The sensor detects the absolute angular position of a permanent magnet attached to a rotating shaft. The magnet configurations and shapes are flexible, but typically the MA800 is used with a diametrically-magnetized cylinder of 2 mm to 8 mm in diameter. The MA800 features programmable magnetic field strength thresholds, allowing the implementation of a push or pull button function outputted as two logic signals.

All MagAlpha sensors offer on-chip, non-volatile memory storage for configuration parameters, including the reference zero-angle position, ABZ encoder settings, and magnetic field detection thresholds in a QFN-16 (3 mm x 3 mm) package.

Features

• 8-bit, 12-bit, and 14-bit resolution absolute angle encoders
• SpinAxis™ hall measurement technique provides instantaneous angle position in digital format
• SPI and SSI (MA800) serial interface for digital angle readout and chip configuration
• Incremental 10-bit and 12-bit ABZ quadrature encoder interface with programmable pulses per turn from 1-256 or 1-1024 (MA730)
• Contactless sensing for long life
• Operates on 3.3 V and 12 mA supplies
• Operating temperature range: -40°C to +125°C
• PWM output 12-bit and 14-bit (MA702 and MA730)
• Available in QFN-16 (3 mm x 3 mm) package

MA730 Sensor Schematic