Inductive sensor simplifies position sensing

Melexis introduces a 16-bit inductive sensor for robotics, industrial, and mobility applications. The new dual-input MLX90514 delivers absolute position with high noise immunity through its SSI output protocol.

Applications such as robotic joint control, industrial motor commutation, and e-mobility drive systems require sensors with high-precision feedback, compact form factor, low-latency response, resilience to environmental stressors, and seamless integration, Melexis explained.

These sensors also need to overcome the limitations of optical encoders and magnetic-based solutions, the company said, which the MLX90514 addresses with its contactless inductive measurement principle. This results in stable and repeatable performance in demanding operational environments.


The inductive measurement principle operates without a permanent magnet, reducing design effort, and the sensor’s PCB-based coil design simplifies assembly and reduces costs, Melexis added.


In addition, the sensor is robust against dust, mechanical wear, and contamination compared with optical solutions. The operating temperature ranges from ‐40°C to 160°C.

Melexis' MLX90514 inductive sensor.(Source: Melexis)

The inductive sensor’s dual-input architecture simultaneously processes signals from two coil sets to compute vernier angles on-chip. This architecture consolidates position sensing in a single IC, reducing external circuitry and enhancing accuracy.

The MLX90514 also ensures synchronized measurements, and supports enhanced functional safety for applications such as measuring both input and output positions of a motor in e-bikes, motorcycles, or robotic joints, according to the company.

Targeting both absolute rotary or linear motion sensing, the MLX90514 provides up to 16-bit position resolution and zero-latency measurement with accuracy better than 0.1° for precise control in demanding environments. Other features include a 5-V supply voltage, coil diameters ranging from 20 mm to 300 mm, and linear displacements of up to 400 mm.

The inductive sensor offers plug-and-play configuration. Engineers only need to program a limited set of parameters, specifically offset compensation and linearization, for faster system integration.

The MLX90514 inductive sensor interface IC is available now. Melexis offers a free online Inductive Simulator tool, which allows users to design and optimize coil layouts for the MLX90514.