High-resolution 22-bit inductive encoder unveiled

Melexis has announced the MLX90520, the new market reference inductive encoder IC with 22-bit resolution for rotary and linear movement. The IC fulfils the demand for high-accuracy, cost-effective position sensing in robotics and large machinery joints between 20mm and 200mm in diameter.

The precise positional sensing of mechanical joints is critical for the rapid, repeatable, and safe operation of robots, automated systems, construction and agricultural machinery. Although optical encoders have been conventionally employed, the market’s need for improved manufacturing efficiency, system reliability, and lower production costs is prompting a search for more practical substitutes.

The device is a high-precision 22-bit resolution encoder delivering low-noise and zero-latency inductive position sensing for rotary and linear movements (up to 400mm). This facilitates safe and repeatable control of large mechanical arms, linear actuators and other rotating assemblies. It presents significant size and robustness advantages over traditional optical encoders and offers SPI or SSI output.

For large through-shaft applications, the slim profile of the module enabled by the device (less than 3mm, including the IC, PCB, and target) permits the development of more compact and simplified mechanical assemblies in comparison to optical or magnetic encoder counterparts, which require large magnets. The inductive sensors’ inherent immunity to dust and other contaminants ensures long-term reliability in robots. Further improving functional safety is the integration of on-board digital processing and the up to SIL 3 system-level compliance, thereby ensuring operational safety.

Beyond enabling precise and repeatable operation, the inductive sensor presents a cost advantage over traditional optical counterparts. This is achieved through the lower initial component cost of the inductive interface MLX90520 compared to optical encoders, as well as the streamlined system integration and development, with the device requiring only a few parameters to be configured before operation.

“With the inductive MLX90520, we are equipping the robotics industry with an alternative to optical encoders that delivers high performance, competitive pricing, and simple development, helping engineers to scale their applications,” said Lorenzo Lugani, product line director at Melexis. “The device has already seen a positive reception by many companies and will help our customers to drive future market success.”