Ams introduces the first inductive position sensor for high-speed motor applications

     AMS introduces the AS5715, the first inductive position sensor for high-speed automotive and industrial motors. The new rotor position sensing solution based on the AS5715 offers the accuracy and latency of rotary transformers widely used in high-speed motors, while significantly reducing material costs, size and weight. What's more, since the IC is based on the automotive functional safety integrity level ASIL-C and the redundancy scheme supports ASIL-D, the solution is fully compliant with ISO 26262 functional safety standards.

     The commercialization of AMS 'inductive position sensor semiconductor technology marks a significant advance in the electrification of automotive systems such as power steering and traction motors for electric and hybrid vehicles. The AS5715 inductive sensor is highly configurable and can be placed in axial (shaft end) and off-axis (through-axis or side-axis) topologies, and can be used with a variety of multipole logarithmic motors.

     Chris Feige, Executive vice president, Headphone and Automotive, AMS, said: "With the introduction of the AS5715, AMS is also taking a major step forward in enabling the technology that will make tomorrow's cars greener, safer, smarter and more comfortable. Motors with the AS5715 will be lighter and will be able to deliver a smoother and more powerful output. "This, combined with the cost savings, makes it a good reason for automakers to adopt the AS5715 inductive sensor instead of expensive and bulky rotary transformers."

     The AS5715's breakthroughs in performance, size and cost will impact a rapidly growing market. By value, the overall motor (including traction motors) market is expected to grow at a CAGR of 8.3% and is estimated to reach $34.6 billion in 2021. At the same time, the automotive motor market is also changing, with permanent magnet synchronous motors (PMSM) replacing brushless DC motors in many high-speed applications.

     In response to the climate crisis, government regulations around the world are also imposing tougher requirements on the automotive industry to reduce the overall average fuel consumption of vehicles. By replacing traditional electromechanical and hydraulic vehicle systems with efficient electronically controlled motors, automakers can more easily achieve their goals of controlling energy consumption.

     The AS5715 enables high-precision, low-delay position measurements that contribute to the smooth operation of the motor control system, allowing high-speed motors to maximize torque, reduce torque ripple, and increase efficiency. With the AS5715 IC and easy-to-use associated coils printed on a low-cost PCB, the position sensor system achieves accuracy up to ±0.3° in a wide range of motors up to 100,000 rpm, including quadrupole logarithmic PMSM.

     Even developers who have previously worked with rotary transformers will be easily familiar with the AS5715's operation mode. The AS5715 offers two pairs of differential analog outputs, sine wave and cosine wave. Sine and cosine waves can be resolved into angular measurements by using the inverse tangent function in the host controller. Ams provides comprehensive documentation and application guidance on how to design Tx and Rx coils in static sensor PCBS, as well as rotating target components fixed to the rotor.The AS5715 also supports automotive manufacturer programs to meet ISO 26262 functional safety standard requirements. By installing two AS5715 ics on the sensor board, a fully redundant measurement system can be achieved.