OSRAM AS5601-SO_EK_AB

The AS5601 is an easy-to-program magnetic rotary position sensor with incremental quadrature (A/B) and 12-bit digital outputs. Additionally, the PUSH output indicates fast airgap changes between the AS5601 and magnet which can be used to implement a contactless pushbutton function in which the knob can be pressed to move the magnet toward the AS5601. This AS5601 is designed for contactless encoder applications, and its robust design rejects the influence of any homogenous external stray magnetic fields. Based on planar Hall sensor technology, this device measures the orthogonal component of the flux density (Bz) from an external magnet. The industry-standard I²C interface supports user programming of non-volatile parameters in the AS5601 without requiring a dedicated programmer. The AS5601 also provides a smart low-power mode which automatically reduces power consumption. The AS5601 is a Hall-based rotary magnetic position encoder that converts the magnetic field component perpendicular to the surface of the chip into voltages which are used to produce incremental A/B outputs and absolute position indication in registers that can be read over an industry-standard I²C bus. The analog signals from the Hall sensors are first amplified and filtered before being converted by the analog-to-digital converter (ADC) into binary data. The output of the ADC is processed by the hardwired CORDIC block (Coordinate Rotation Digital Computer) to compute the angle and magnitude of the magnetic field vector. The intensity of the magnetic field is used by the automatic gain control (AGC) to adjust the amplification level to compensate for temperature and magnetic field variations. The angle value provided by the CORDIC algorithm is used by the internal logic to generate the incremental quadrature signals A and B. The magnitude and AGC value is dynamically monitored and generates the PUSH output for fast changes of the airgap between the magnet and the AS5601. Very slow changes are suppressed to provide a robust and reliable pushbutton output that tolerates temperature variation and magnet degradation. The AS5601 is programmed through an industry-standard I²C interface to write an on-chip one-time programmable (OTP) memory. This interface can be used to program a zero angle and to configure the chip. The AS5601 is powered from a 5.0V supply using the on-chip LDO regulator, or it can be powered directly from a 3.3V supply. The internal LDO is not intended to power other external ICs and needs a 1μF capacitor to ground. In 3.3V operation, the VDD5V and VDD3V3 pins must be tied together. VDD is the voltage level present at the VDD5V pin. The AS5601 supports the 2-wire Fast-mode Plus I²C -slave protocol in device mode, in compliance with the NXP Semiconductors (formerly Philips Semiconductors) specification UM10204. A device that sends data onto the bus is a transmitter and a device receiving data is a receiver. The device that controls the message is called a master. The devices that are controlled by the master are called slaves. A master device generates the serial clock (SCL), controls the bus access, and generates the START and STOP conditions that control the bus. The AS5601 always operates as a slave on the I²C bus. Connections to the bus are made through the open-drain I/O lines SDA and the input SCL. Clock stretching is not included. The host MCU (master) initiates data transfers. The 7-bit slave address of the AS5601 is 0x36 (0110110

• Encoder replacement
• Contactless rotary knobs with push buttons
• Other angular position measurement solutions