1. Core Functionality: Rotary Position Sensor

️· The AS5043 is a magnetic rotary position sensor. It detects the angle of a rotating magnet.
️· It provides both digital and analog outputs representing that angle.

2. Digital Output (SSI - Serial Synchronous Interface)

️· Data Representation: The digital output is a serial bitstream representing the angle.
️· Status Flags: The digital output includes status flags that indicate:
- Magnetic field strength and position.
- Error conditions (e.g., out-of-range magnetic field).
️· Daisy-chaining (Multiple Sensors): The sensor can be used in a "daisy-chain" configuration, allowing multiple sensors to be connected in series for more complex position tracking. This uses the SSI interface.
️· Diagnostic Status: Status bits reflect sensor health and magnetic field position.
️· Error Indication: Flags signal errors like broken power supply or a magnetic field out of range.

3. Analog Output

️· Voltage Proportional to Angle: The analog output is a voltage (0V to potentially close to VDD – the supply voltage) that's directly proportional to the detected angle.
️· Ratiometric: The analog output is *ratiometric* meaning its voltage depends on the supply voltage (VDD). This makes it less sensitive to changes in the supply voltage itself.
️· Reference Voltage: The reference voltage for the Analog-to-Digital Converter (DAC) can be internally derived from VDD, or it can be supplied externally via DACref pin.
️· Diagnostic Mode: The analog output can be put in a diagnostic mode where it's automatically turned off in case of error conditions (out-of-range magnetic field, broken power supply).
️· OTP Configuration: A One-Time Programmable (OTP) option allows to permanently enable/disable diagnostic mode for analog output.
️· Output Range: Programmable output ranges are available using OTP.
- Full Scale Mode: 0-100% of Vref.
- Diagnostic Mode: 10-90% of Vref.

4. Key Features & Configuration

️· Angular Range Selection: The sensor allows selection of different angular ranges (360°, 180°, 90°, 45°) for the digital and analog outputs.
️· Fine-Tuning: The gain of the OPAMP buffer stage can be adjusted to fine-tune the angular range.
️· Supply Voltage: Operates on a supply voltage between 3.0V and 5.5V (VDD).
️· One-Time Programmable (OTP): Allows configuration of some sensor parameters, including disabling/enabling diagnostic features.

5. Important Terminology

️· SSI: Serial Synchronous Interface (Digital Output)
️· DAC: Digital-to-Analog Converter
️· VDD: Positive Supply Voltage
️· DACref: External DAC Reference Voltage
️· OTP: One-Time Programmable