The AS5130 is a contactless magnetic rotary encoder from Austria Microsystems that provides accurate angular measurement over a full turn of 360°. It is a system-on-chip that combines integrated Hall elements, analog front end and digital signal processing in a single device. The angle can be measured using only a simple two-pole magnet rotating over the center of the chip. The magnet may be placed above or below the IC. The absolute angle measurement provides instant indication of the magnet’s angular position with a resolution of 8 bit = 256 positions per revolution. This digital data is available as a serial bit stream and as a PWM signal. The AS5130 can be operated in pulsed mode (Vsupply=off), which reduces the average power consumption significantly. During Vsupply=off, the measured angle can be stored using an internal storage register supplied by a low power voltage line. This mode achieves very low power consumption during polling of the rotary position of the magnet. If the position of the magnet changes, then the motion detection feature wakes up an external system. The device is capable of counting the amount of magnet revolutions. The multi turn counter value is stored in a register and can be read in addition to the angle information. Furthermore, any arbitrary position can be set as zero-position. The system is tolerant to misalignment, magnet's physical shape and non-uniformity of the magnetic field.
