Speaker
Description
Performance of planar Hall magnetoresistive (PHMR) sensors was measured in different specification, such as sensor layer thickness, geometry [1]. We figured out the change in PHMR sensor performance for each factors and applied into magnetic encoder experiments. In this magnetic encoder experiments, PHMR sensor was located near to steel gear and permanent magnet was located behind the PHMR sensor to induce stray field from magnetized steel gear. Signal from PHMR sensor was compared in different factors, such as distance between gear-sensor, distance between sensor-magnet or direction of sensor and magnet, etc. Total harmonic distortion (THD), signal amplitude and phase difference were main performance requirements, but those are not satisfied in our traditional multi-ring type NiFe/IrMn bilayer sensors. New ferromagnetic material and sensor geometry were applied to encoder sensors to enhance the main performance requirements and the experimental result was discussed in this speech.
Fig. 1 Optical microscope image of PHMR sensor (left) and magnetic encoder using PHMR sensor (right).
Acknowledgements
This research was supported by a National Research Foundation (NRF) grant funded by the MSIT (Grant No. NRF-2018R1A5A1025511).
References
[1] T. Jeon et al., “Operational Parameters for Sub-Nano Tesla Field Resolution of PHMR Sensors in Harsh Environments,” Sensors, vol. 21, no. 20. MDPI AG, p. 6891, Oct. 18, 2021. doi: 10.3390/s21206891.
