CMOS SC-spinning, current-feedback hall sensor for high speed and low cost applications

Abstract

A low cost, high speed Hall sensor for motor application is presented. The Hall sensor, its signal conditioning amplifier, Hall plate and Hall biasing circuit are fully integrated in a single chip. The Hall device is a single plate configuration made by only standard mask process for low cost feature. The signal conditioning amplifier applied the noise shaping and offset filtering by chopping technique, also designed by current-feedback approach to broaden its operational speed. The Hall biasing circuit designed by proposed signal-chopped spinning current method (sc-spinning current) to combine spinning current and chopping signal into Hall biasing circuit, which ease feed-forward path design and decrease the poles in signal path. The Hall sensor has typical offset of 600 nV. The sensing speed can operate more than 400kHz operation bandwidth.