Experimental Assessment of a Broadband Current Sensor based on the X-Hall Architecture

The X-Hall sensor is presented, characterized and proposed as a viable architecture for silicon-integrated, broadband, current/magnetic-field measurements. The X-Hall architecture overcomes the methodological bandwidth limit of state-of-the-art Hall-effect sensors by replacing the typically used spinning-current technique with a DC bias-based, passive offset compensation technique, which is less effective from an absolute standpoint but presents the key feature of being frequency independent.Three different prototypes have been realized and experimentally characterized in both static and dynamic operation. Static characterization demonstrates a competitively low residual offset of the X-Hall sensor with respect to spun Hall sensors operated at high frequency. Even though physical simulations reveal a theoretical bandwidth limit set at 200 MHz for the X-Hall sensor, experimental dynamic characterization on the prototypes identifies the presence of additive dynamic perturbations limiting the sensor bandwidth, which are attributable to technology issues in the practical implementation of the prototypes. Nevertheless, it is possible to compensate these perturbations through a vector differential measurement model, so that a bandwidth of 4 MHz is demonstrated, which is the broadest bandwidth ever achieved by a purely Hall-effect based sensor, to the best of knowledge of the authors.