Signal conditioning and processing for metallic Hall sensors.

Two electronics prototypes for the ITER outer vessel steady-state magnetic field Hall sensors based on a lock-in signal processing and current spinning technique were developed. The prototypes, the first using a rectangular lock-in signal processing with sensor offset cancellation and the second employing advanced lock-in signal processing with sensor and electronics offset cancellation, were compared with a DC technique and commercial lock-in amplifier. The influence of long interconnection cables, white noise, and interfering planar Hall effect to a measurement accuracy was evaluated. The planar Hall voltage suppression by the current spinning technique was investigated. Whilst the rectangular lock-in amplifier prototype failed to meet the ITER accuracy requirement, the advanced lock-in amplifier prototype demonstrated required functionality and accuracy. [ABSTRACT FROM AUTHOR]