An integrated microsystem for 3-D magnetic field measurements

Abstract

In this paper, we present a portable, battery-operated, three-dimensional magnetic microsystem (magnetodosimeter), 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-m CMOS technology, is sensitive to magnetic fields ranging from 0200 to +200 mT, achieving 12 bits of resolution, 11 bits of linearity, and an overall accuracy better than 1% in the temperature range from 020 to +80 C.

CMOS magnetic field to frequency converter

“…The controlled current is used to discharge the output node from to . If the state transition time for this latch can be neglected, the delay time of this delay element can be expressed as (3) where is the capacitive load of the output node. Two current sources are used to compensate the clock feed-through coupling because this clock feed-through would result in the distortion of the duty cycle [8].…”

“…There are a lot of industrial applications where magnetic sensors can be found [1], [2], such as brushless motor controls, current measurement, monitoring the exposure to magnetic field [3], automotive applications, etc. Integrated microsensors with on-chip interface circuits are currently replacing discrete sensors in view of their inherent advantages, such as low cost, high reliability, and on-chip processing capability.…”

Magnetic-to-Digital Converters Using Single-Amplifier-Based Second-Order Delta–Sigma Modulators

“…T HERE IS A trend to convert magnetic fields into their corresponding electrical information to be helpful to human knowledge by using different kinds of magnetic sensors, such as Hall sensors, spinning current Hall sensors, and magnetic MOSFETs (MAGFETs) [1]- [8]. The MAGFETs with two split drains can sense the perpendicular magnetic field to produce the corresponding current.…”

High Sensitivity Dual-Gate Four-Terminal Magnetic Sensor Compatible With SOI FinFET Technology

“…T HE magnetic sensitive (MS) smart-power integrated circuits (ICs) are used for detecting the position or rotation of magnetized objects [1], [2], portable battery-operated magnetodosimeters [3] and galvanic current sensing for over current protection [4], amongst other various applications. The desire to increase device density (lower cost) and functionality (better signal-to-noise ratio, higher reliability) of the MS ICs requires on-chip integration of the magnetic sensors into the mainstream CMOS technology [5].…”