Magnetic encoders are more durable than optical encoders, but offer limited resolutions. This compact design uses a proprietary reluctor-wheel, and a custom ASIC (Application Specific Integrated Circuit) to achieve up to 512 cpr (counts per revolution).
A reluctor-wheel, with magnetic domains on its edge surface, rotates with the motor shaft. Hall elements pick up flux-density changes as each domain passes by. The ASIC processes and conditions the encoder signals, and the resulting position feedback is transmitted to the controller.
The dual-channel encoder with digital output is integral on 15-mm, 22-mm, and 23-mm micromotors. No assembly, soldering, cable making, or termination additions are required. Signals are CMOS- and TTL-compatible.
Stephen O'Neil, MicroMo Electronics Inc., 14881 Evergreen Ave., Clearwater, FL 33762-3008; (813) .