The ams 47 series magnetic angular position sensors save high-speed motor systems from using an external microcontroller or DSP to compensate errors due to propagation delays, by featuring the unique built-in Dynamic Angle-Error Compensation (DAEC™) algorithm.
Traditional magnetic rotary position-sensor ICs can take 100-200μs to convert magnetic field strength readings into digital angle measurements. During this delay, a spinning rotor’s angular displacement changes, so that its actual position when the digital output leaves the sensor differs from its measured position. The resulting error increases directly with rotor speed: for a propagation delay of 100μs, the dynamic angle error is 1.2° at 1,000rpm and 12° at 10,000rpm.
DAEC dynamically compensates for the rotor speed at the time each sample is captured, and responds automatically to changes in speed. This allows the 47 series sensors to provide angle measurements accurate to ± 0.08° at 7,000rpm, ± 0.14° at 12,000rpm and ± 0.17° at 14,500rpm.
The sensors are suitable for all motor-control and angle-measurement applications, and provide digital-PWM absolute-position measurement as well as UVW outputs for use in field-oriented commutation, and an ABI output allowing use as an optical-encoder replacement. In high-speed BLDC motors and Permanent-Magnet Synchronous Motors (PMSM), the sensor’s high accuracy enhances execution of the commutation scheme, resulting in higher torque and efficiency, lower torque ripple and smoother operation.
The 47 series position sensors include the AS5047D, AS5147 and AS5247. The AS5047D is suitable for industrial applications, while the AEC-Q100 qualified AS5147 is ideal for applications such as automotive electronic power steering and pumps. The dual-die AS5247 is also AECQ100 qualified, for automotive applications requiring the highest level of functional-safety compliance.
- Robots and encoder modules
- Building automation
- Factory automation
- Stepper-motor control
- Automotive motor controls
- Resolution: 2000 steps per revolution (decimal mode); 2048 steps (ABI mode)
- 14-bit resolution (0.022°) digital SPI output
- Proven differential-sensing technique
- High immunity to stray magnetic fields
- 14-pin TSSOP package (AS5047D, AS5147);7mm x 7mm MLF-40 (AS5247)