%0 Conference Paper %1 mohamed2021readout %A Mohamed, A. %A Heidari, H. %A Anders, J. %B ESSCIRC 2021 - IEEE 47th European Solid State Circuits Conference (ESSCIRC) %D 2021 %K myown iis from:aymanmohamed %T A readout circuit for tunnel magnetoresistive sensors employing an ultra-low-noise current source %X We present a tunneling magnetoresistive (TMR) sensing microsystem consisting of a low flicker noise TMR sensor and a custom integrated readout frontend. The proposed sensor readout circuit introduces a novel ultra-low-noise current biasing scheme for the TMR sensor, which achieves a very low current noise floor of 2.2 pA/sqrt(Hz) for a 1mA biasing current. The TMR output voltage is processed by a differential readout scheme to improve the baseline-to-signal ratio. The microsystem also features an on chip 10-bit current DAC that allows compensating for the large process variations in the TMR base resistance value. The readout chip is manufactured in a 180nm SOI CMOS technology and heterogeneously integrated with the TMR sensor. The readout chain provides a thermal noise floor of 4 nV/sqrt(Hz), while, together with the biasing scheme, consuming a total power of 38mW. The complete sensor system consisting of the TMR and the readout circuit provides a state-of-the-art magnetic field noise floor of 120 pT/sqrt(Hz).

@inproceedings{mohamed2021readout, abstract = {We present a tunneling magnetoresistive (TMR) sensing microsystem consisting of a low flicker noise TMR sensor and a custom integrated readout frontend. The proposed sensor readout circuit introduces a novel ultra-low-noise current biasing scheme for the TMR sensor, which achieves a very low current noise floor of 2.2 pA/sqrt(Hz) for a 1mA biasing current. The TMR output voltage is processed by a differential readout scheme to improve the baseline-to-signal ratio. The microsystem also features an on chip 10-bit current DAC that allows compensating for the large process variations in the TMR base resistance value. The readout chip is manufactured in a 180nm SOI CMOS technology and heterogeneously integrated with the TMR sensor. The readout chain provides a thermal noise floor of 4 nV/sqrt(Hz), while, together with the biasing scheme, consuming a total power of 38mW. The complete sensor system consisting of the TMR and the readout circuit provides a state-of-the-art magnetic field noise floor of 120 pT/sqrt(Hz).}, added-at = {2021-06-28T08:50:01.000+0200}, author = {{Mohamed}, A. and {Heidari}, H. and {Anders}, J.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2a88bf850e2e6e1a973ea5f85ab9541e1/iis}, booktitle = {ESSCIRC 2021 - IEEE 47th European Solid State Circuits Conference (ESSCIRC)}, interhash = {d5003e061340de3b002151a15190b32a}, intrahash = {a88bf850e2e6e1a973ea5f85ab9541e1}, keywords = {myown iis from:aymanmohamed}, month = {sept}, timestamp = {2021-06-28T06:50:01.000+0200}, title = {A readout circuit for tunnel magnetoresistive sensors employing an ultra-low-noise current source}, year = 2021 }