Japanese electronics firm Renesas has introduced magnet-free inductive position sensor (IPS) ICs for use in robotics, medical and healthcare, smart buildings, home appliances, and motor commutation.

They can be customised for various coil designs and are compatible with a wide range of industrial applications. Built for high resolution, precision and robustness, the RAA2P3226, RAA2P3200 and RAA2P4200 sensor ICs offer a cost-effective alternative to traditional magnetic and optical encoders, which can be bulky and expensive, and require frequent maintenance. Renesas also launched a web-based design tool that helps users create custom sensing elements.

Operating on non-contact coil sensor technology, the IPS products use a simple metallic target and dual-coil or single-coil configurations to detect absolute rotary, linear or arc positions. These sensor ICs are designed to maintain stable operation even in environments with elevated temperatures from -40 to +125˚C, particulate matter, moisture, mechanical vibration and electromagnetic interference. Moreover, they are immune to stray magnetic fields and require no maintenance, unlike magnetic- or optical encoder-based sensors.

Their durability and low upkeep make them a reliable and cost-effective sensing option for motor drives, actuators, valves, service robots and infrastructure applications, where reliability and long-term performance are critical.

All three offer precision in detecting target positions, with accuracy better than 0.1 per cent of the full-scale electrical range. Two of them, the RAA2P3226 and RAA2P3200, operate at 600k RPM (electrical) with propagation delays under 100ns for high-speed motor applications. The RAA2P3226 supports dual-coil sensing with up to 19bit resolution and 0.01˚ absolute accuracy, providing the precision performance required for robotic applications.

The RAA2P4200 targets low-speed applications such as medical devices and power tools and the RAA2P3200 is for high-speed motor commutation. All three include automatic calibration and linearisation to simplify integration and improve system-level performance.

Renesas will also introduce automotive-grade IPS units, the RAA2P452x and RAA2P4500, which will be available later this year. The dual-channel RAA2P452x lets users achieve Asil-D safety compliance when paired with Renesas MCUs. This automotive-grade product offers a cost-effective option for low-speed body control and chassis systems without compromising quality.

Designing with inductive position sensors typically involves integrating a PCB, an IC with passive components and a metal target mounted to the moving part. The most complex part is the external sensing element, such as the transmitter and receiver coils, which must be precisely configured to realise accuracy and customised to the system’s mechanical and environmental requirements.

Renesas’ web-based TPS coil optimiser tool tackles this by automating coil layout, simulation and tuning, reducing the learning curve for developers. With this tool, engineers can also obtain accurate performance estimates and overcome manufacturing constraints by optimising the coil layout.

“Our new web-based coil design tool is a game changer for inductive position sensing,” said Leopold Beer, vice president at Renesas. “In the past, developers had to rely on chip suppliers for technical expertise when working with inductive position sensors. We completely removed this hurdle. This intuitive tool lets developers fully customise the sensing element and automatically fine-tune it to achieve maximum accuracy and robustness at the system level. This dramatically lowers the barrier of entry and enables more customers, regardless of their expertise level, to confidently integrate inductive position sensing into their designs.”

The devices are available in volume production, along with evaluation kits. The automotive-grade RAA2P452x and RAA2P4500 will be in production towards the end of this year. The IPS coil optimiser (www.renesas.com/en/software-tool/inductive-position-sensor-coil-optimizer) is available now and supports all Renesas IPS products (www.renesas.com/IPS).