AS5045

Data Sheet

www.austriamicrosystems.com

Revision 1.7

12 – 33

7

Functional Description

The AS5045 is manufactured in a CMOS standard process and uses a spinning current Hall technology for sensing

the magnetic field distribution across the surface of the chip.

The integrated Hall elements are placed around the center of the device and deliver a voltage representation of the

magnetic field at the surface of the IC.

Through Sigma-Delta Analog / Digital Conversion and Digital Signal-Processing (DSP) algorithms, the AS5045

provides accurate high-resolution absolute angular position information. For this purpose a Coordinate Rotation

Digital Computer (CORDIC) calculates the angle and the magnitude of the Hall array signals.

The DSP is also used to provide digital information at the outputs M agI NCn and M agD E Cn that indicate

movements of the used magnet towards or away from the device’s surface.

A small low cost diametrically magnetized (two-pole) standard magnet provides the angular position information (see

Figure 17

).

The AS5045 senses the orientation of the magnetic field and calculates a 12-bit binary code. This code can be

accessed via a Synchronous Serial Interface (SSI). In addition, an absolute angular representation is given by a

Pulse Width Modulated signal at pin 12 (PWM). This PWM signal output also allows the generation of a direct

proportional analogue voltage, by using an external Low-Pass-Filter.

The AS5045 is tolerant to magnet misalignment and magnetic stray fields due to differential measurement technique

and Hall sensor conditioning circuitry.

Figure 4. AS5045 Block Diagram