Temperature Drift of Offset and Sensitivity in Full-Bridge Magnetoresistive Sensors

Vopálenský, Michal; Platil, Antonin

doi:10.1109/tmag.2012.2220535

Cited by 32 publications

(16 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Compared with studies reported in previous publications [3] [5], measurements were performed for a larger number of chips and also both bridges were used. This allows comparing the offset voltages between the sensors.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Determination of the aging offset voltage of AMR sensors based on accelerated degradation test

Zambrano

Kerkhoff

2015

2015 IEEE 20th International Mixed-Signals Testing Workshop (IMSTW)

View full text Add to dashboard Cite

Usually Anisotropic Magnetoresistance angle sensors are configured with two Wheatstone bridges, but an undesirable offset voltage included in the sensor output affects its accuracy. The total offset voltage combines a voltage due to resistance mismatches during manufacturing and a voltage from inequalities in the magnetic sensitivity. This paper focuses on identifying a consistent trend between the bridges' offset voltages. Compared with previous studies that focus on lifetime tests using high temperatures, this research uses temperature cycling to study offset voltage and sensitivity variations due to aging effects.A consistent trend between the bridges' offset voltages could not be found. The two offset components can add to or subtract from each other and their interaction can change over time due to variations in the sensor's material properties. To achieve a precise angle measurement, the offset voltage must be compensated continuously over the entire sensor lifetime.

show abstract

Section: Discussionmentioning

confidence: 99%

“…Offset voltage is a known AMR sensor characteristic, as well as is its variations because of temperature [3]. However, it is not the same regarding the offset voltage variation resulting from the aging effect [4].…”

Section: Introductionmentioning

confidence: 99%

Determination of the aging offset voltage of AMR sensors based on accelerated degradation test

Zambrano

Kerkhoff

2015

2015 IEEE 20th International Mixed-Signals Testing Workshop (IMSTW)

View full text Add to dashboard Cite

show abstract

“…The unbalance is proportional to the resistance value having a stronger influence for small values of resistors. This double effect implies a limitation of the sensors sensitivity, which is enhanced for applications with operations in high temperature swing [10,11]. Graphs of Fig.…”

Section: R((p) = R 0 + R a Cos 2 ((P)mentioning

confidence: 99%

Lock-in amplifiers for AMR sensors

Díaz-Michelena

Cobos

Aroca

2015

Sensors and Actuators A: Physical

View full text Add to dashboard Cite

Anisotropic magnetoresistive (AMR) magnetic sensors are often chosen as the magnetic transducer for magnetic field sensing in applications with low to moderate magnetic field resolution because of the relative low mass of the sensor and their ease of use. They measure magnetic fields in the order of the Earth magnetic field (with typical sensitivities of l%o/G or 1CH%O/UT), have typical minimum detectable fields in order of nT and even 0.1 nT but they are seriously limited by the thermal drifts due to the variation of the resistivity with temperature (~2.5%o/°C) and the variation of the magnetoresistive effect with temperature (which affects both the sensitivity of the sensors: ~2.7%o/°C, and the offset: ±0.5%o/°C). Therefore, for lower magnetic fields, fluxgate vector sensors are generally preferred.In the present work these limitations of AMR sensors are outlined and studied. Three methods based on lock-in amplifiers are proposed as low noise techniques. Their performance has been simulated, experimentally tested and comparatively discussed. The developed model has been also used to derive a technique for temperature compensation of AMR response. The final goal to implement these techniques in a space qualified applied specific integrated circuit (ASIC) for Mars in situ exploration with compact miniaturized magnetometers.

show abstract

“…Several approaches have been reported to improve the stability [9], [10], but there is still a temperature dependence that becomes critical when measuring weak magnetic fields in environments with an extended operating temperature range. The effect of temperature in the sensitivity is linear [7], [11] and can be easily calibrated.…”

Section: B Temperature Measurements For Thermal Calibrationmentioning

confidence: 99%

A Front-End ASIC for a 3-D Magnetometer for Space Applications by Using Anisotropic Magnetoresistors

et al. 2015

View full text Add to dashboard Cite

This paper presents an application-specific integrated circuit (ASIC) aimed for an alternative design of a digital 3-D magnetometer for space applications, with a significant reduction in mass and volume while maintaining a high sensitivity. The proposed system uses magnetic field sensors based on anisotropic magnetoresistances and a rad-hard mixed-signal ASIC designed in a standard 0.35 µm CMOS technology. The ASIC performs sensor-signal conditioning and analogue-to-digital conversion, and handles calibration tasks, system configuration, and communication with the outside. The proposed system provides high sensitivity to low magnetic fields, down to 3 nT, while offering a small and reliable solution under extreme environmental conditions in terms of radiation and temperature.Index Terms-Aerospace electronics, anisotropic magnetoresistance (AMR), CMOS mixed-signal application-specific integrated circuit (ASIC), magnetometer, radiation hardened by design (RHBD).

show abstract

Temperature Drift of Offset and Sensitivity in Full-Bridge Magnetoresistive Sensors

Cited by 32 publications

References 8 publications

Determination of the aging offset voltage of AMR sensors based on accelerated degradation test

Determination of the aging offset voltage of AMR sensors based on accelerated degradation test

Lock-in amplifiers for AMR sensors

A Front-End ASIC for a 3-D Magnetometer for Space Applications by Using Anisotropic Magnetoresistors

Contact Info

Product

Resources

About