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In this paper an integrated CMOS front-end circuit for a micro-integrated Fluxgate magnetometer is proposed. The system is based on excitation block, that feeds the excitation coil of the sensor and a read-out block that sense the voltage of the pick-up coils. To sense the output signal, the second harmonic detection principle has been chosen to achieve a good compromise between power consumption and noise requirements. An integrated low pass Sallen-Key filter has been used to extract the dc signal after the demodulation. The preliminary measurements, performed with a PCB sensor, show a sensitivity of 920 V/T and a linearity error of 6% full scale. The circuit has been realized in a standard 0.35 um CMOS process. The power consumption is 8 mW @ 3.3V for the excitation and read-out parts and unit and 42 mW @ 5V for the output power stage. © 2006 IEEE.

A complete vector-2D integrated microsensor system for magnetic field measurement is proposed. The system consists of a micro-integrated fluxgate magnetometer with front-end electronic circuitry based on second-harmonic detection. The magnetic core of the sensor is realized with the VITROVAC 6025X deposited over the micro-integrated coils with the dc-magnetron sputtering deposition process. The sensor realized shows a linearity error of about 1.15% of the full scale in the range of +/- 50 mu T with a sensitivity of 0.45 mV/mu T. (c) 2006 Elsevier B.V. All rights reserved.

A high-sensitivity vector two-dimensional (2-D) magnetic sensor system for low magnetic field measurements has been realized and tested. The system, made in PCB technology, consists of a double-axis Fluxgate magnetic sensor and the readout electronic circuitry, based on second-harmonic detection. The amorphous magnetic materials Vitrovac 6025X (25 mu m thick) and Vitrovac 6025Z (20 mu m thick) were used as the ferromagnetic core of the sensor. By applying a sinusoidal excitation current having a 450-mA peak at 10 kHz with Vitrovac 6025Z, the measured magnetic sensitivity was about 1.25 mV/mu T. This value seems to be adequate for the Earth's magnetic field detection (+/- 60 mu T). The fullscale linearity error was about 1.5%. By using the thicker Vitrovac 6025X and a sinusoidal excitation current having a 600-mA peak at 10 kHz, a maximum sensitivity of approximately 1.68 mV/mu T with a linearity error of about 1.55% full scale in the range of 60 mu T were measured. Due to the use of commercially available ferromagnetic materials, the vector 2-D magnetic sensor system presented is characterized by a very simple fabrication process, thus allowing low-cost devices to be designed

In this paper, we present a family of fluxgate magnetic sensors on printed circuit boards (PCBs), suitable for an electronic compass. This fabrication process is simple and inexpensive and uses commercially available thin ferromagnetic materials. We developed and analyzed the prototype sensors with software tools based on the finite-element method. We developed both single- and double-axis planar fluxgate magnetic sensors as well as front-end circuitry based on second-harmonic detection. Two amorphous magnetic materials, Vitrovac 6025X (25 mu m thick) and Vitrovac 6025Z (20 pm thick), were used as the ferromagnetic core. We found that the same structures can be made with Metglas ferromagnetic core. The double-axis fluxgate magnetic sensor has a sensitivity of about 1.25 mV/mu T with a linearity error of 1.5% full scale, which is suitable for detecting Earth's magnetic field (+/- 60 mu T full-scale) in an electronic compass

An high sensitivity vector-2D magnetic sensor system for low magnetic field measurements has been realized and tested. The system, realized in PCB technology, consists of a double axis Fluxgate magnetic sensor with its front-end electronic circuitry based on second-harmonic detection. The amorphous magnetic materials Vitrovac 6025X (25 mu m thick) and Vitrovac 6025Z (20 mu m thick) were used as a ferromagnetic core for the sensor. Applying a sinusoidal excitation current of 450 mA peak at 10 kHz with the Vitrovac 6025Z, the magnetic sensitivity was about 1.25 mV/mu T, suitable for detecting the Earth's magnetic field (+/- 60 mu T), while the linearity error is 1.5% full scale. Using the thicker Vitrovac 6025X, a maximum sensitivity of about 1.68 mV/mu T and a linearity error of about 1.55% full scale in the range of +/- 60 mu T were obtained with a larger sinusoidal excitation current of 600 mA peak at 10 kHz. The 2D vector sensor system presented is characterized by a very simple process fabrication due to the use of commercially available very thin ferromagnetic material.