Melexis, a global microelectronics engineering company, has introduced its first inductive sensor IC for the open market. The MLX90510 offers exceptional accuracy of <+/-0.36° at speeds up to 240,000 e-rpm. It is designed for demanding high-speed sensing applications with high accuracy, EMC, and safety requirements. It is intended for use in electric motor (e-axle), electronic brake boost, and electronic power steering applications.
“An efficient electrical drivetrain requires synchronizing the stator supply currents with the rotor position. This leads to optimal efficiency and control of torque characteristics,” says Lorenzo Lugani, Product Manager for Inductive Sensors at Melexis. “Thanks to its digital architecture and robust design, automotive engineers can fully leverage the MLX90510’s EMC robustness with minimal effort from the ECU, resulting in reduced module costs.” The MLX90510 offers differential sinusoidal and cosine analog outputs and is based on a digital architecture. It incorporates Melexis’s patented tracking loop technology.
This innovative architecture offers several advantages:
• The system propagation delay is trimmed to 0ns with a maximum residual variation of +/-120ns across the entire operating temperature range.
• Input offset compensation and zero exit angle position adjustment are performed within the IC, reducing the ECU's workload.
• The 3-phase coil design simplifies linearity optimization.
• Decoupling between input and output enables unprecedented EMC performance. It also guarantees stable output amplitudes regardless of the input signal strength related to the air gap.
The linearization function, with up to 16 calibration points, addresses the nonlinearities of the most challenging sensor modes, such as shaft side-mounted sensors. The MLX90510 works in conjunction with a set of PCB-based coils whose scalable design can be easily adapted to the number of pole pairs in the motor.
By supporting multiple sensing modes for both on-axis (shaft end) and off-axis (shaft side or through-shaft) operation, the IC maximizes flexibility in inductive coil designs to meet the most demanding mechanical constraints. With its overvoltage and reverse polarity protection (+/-24V on the power supply and +/-18V on the outputs), the MLX90510 offers excellent robustness against electrical challenges. Furthermore, the sensor is AEC-Q100 rated for extended operating temperatures from -40°C to +160°C. Fully compliant with the ASIL-C functional safety guidelines of ISO 26262, the MLX90510 is compatible with ASIL-D system-level integration.
