P Gomez et al 2007 J. Phys. D: Appl. Phys. 40 4396 doi:10.1088/0022-3727/40/15/002
P Gomez1, D Litvinov2 and S Khizroev3
Show affiliationsThis paper presents a systematic method to design and calculate tunnelling magneto-resistance (TMR) sensors with high signal-to-noise ratio (SNR). The sensing module consists of four TMR devices arranged in a Wheatstone-bridge configuration. Closed-form equations were obtained to calculate TMR sensor current, array output voltage, magneto-resistance ratio, overall noise (thermal and shot) and SNR for a given bandwidth. Using this technique we were able to maximize the SNR by tuning the many parameters of the TMR devices. Typical SNR values are in excess of 45 dB.
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
85.75.Ss Magnetic field sensors using spin polarized transport
Issue 15 (7 August 2007)
Received 10 October 2006, in final form 5 June 2007
Published 13 July 2007
P Gomez et al 2007 J. Phys. D: Appl. Phys. 40 4396
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