onsemi — NCS32100 Rotary Position Sensor

The onsemi NCS32100 IC is a dual-inductive position sensor interface which offers the high accuracy at high rotation speed required in servo motors and other industrial applications.

An NCS32100-based position sensor system consists of two PCBs:

• A rotor board featuring two printed inductors, and no soldered components on the rotor
• A stator board featuring printed inductors and the NCS32100 encoder IC

Accuracy is better than ±50 arcsec for a 38 mm sensor board. The NCS32100 achieves full accuracy at speeds up to 6,000 rpm, and above this can operate at speeds up to 60,000 rpm with reduced accuracy. Incremental motion is tracked with high precision: the NCS32100 resolves single-turn data to 20 bits, and multi-turn outputs to 24 bits.

onsemi has made it as easy as possible for designers to implement systems based on the NCS32100. The IC includes an integrated MCU with firmware, which means that it produces position and velocity outputs rather than raw analog signals. The device can also be easily configured to work with inductive sensor boards of various sizes.

Flexible arrangements for mechanical assembly include alignment tolerance of ±0.25 mm. Integrated self-calibration accounts for PCB asymmetries, and secondary calibration helps to adjust for mechanical errors.

The NCS32100 inductive sensor system is immune to temperature changes, vibration and contaminants. It can provide position data even when the rotor is not moving.

onsemi supports the NCS32100 chip with a PCB reference design for a 38 mm rotary sensor, firmware, and an evaluation board.