An integrated microsystem for 3-D magnetic field measurements

In this paper, we present a portable, battery-operated, three-dimensional magnetic microsystem (magneto-dosimeter), intended for monitoring the workers´ exposure to magnetic fields in particular working environments, such as hospitals or physics laboratories. The proposed microsystem is based on a multichip module containing three equal channels for the three components of the magnetic field measurement, a microprocessor, and a memory. Each single-chip channel detects the magnetic field, converts it into the digital domain, and delivers the result to the microprocessor by means of an on-chip serial interface. The single-chip channel, fabricated in a 0.8-μm CMOS technology, is sensitive to magnetic fields ranging from -200 to +200 mT, achieving 12 bits of resolution, 11 bits of linearity, and an overall accuracy better than 1% in the temperature range from -20 to +80°C