Hall sensors play a pivotal rule among magnetic sensors. They are used for position sensing, speed control, current sensing and many other applications. Main limits in CMOS Hall sensors are sensitivity and acquisition bandwidth. While there is a strong literature on techniques able to increase sensitivity, bandwidth limits are not well understood. This paper analyzes the transient behavior of CMOS Hall sensor making use of modern physical simulator. A 3D model of a squared Hall sensor in CMOS technology is implemented. Galvanic transport model is used for numerical simulation of magnetic force effects on silicon device. In order to correctly analyze the response time, Mixed-mode SPICE-physical simulations was performed on the whole circuit, i.e. 3D device plus biasing scheme. Simulations show a fast response time for the modeled device, enabling acquisition bandwidth in the MHz range. The settling time partially depends on incident magnetic field and biasing current, while it depends greatly on physical structure of the sensor. Doping concentration of the n-type well is one of the main parameters affecting time response. Faster Hall devices can be realized using higher concentrations of the n-well but this will significantly reduce the sensitivity of the sensor. To our knowledge, this paper is the first one attending to analysis of time limits in CMOS Hall sensors.
Crescentini, M., Romani, A., Sangiorgi, E. (2014). Physical simulations of response time in Hall sensor devices. New York : IEEE [10.1109/ULIS.2014.6813923].
Physical simulations of response time in Hall sensor devices
CRESCENTINI, MARCO;ROMANI, ALDO;SANGIORGI, ENRICO
2014
Abstract
Hall sensors play a pivotal rule among magnetic sensors. They are used for position sensing, speed control, current sensing and many other applications. Main limits in CMOS Hall sensors are sensitivity and acquisition bandwidth. While there is a strong literature on techniques able to increase sensitivity, bandwidth limits are not well understood. This paper analyzes the transient behavior of CMOS Hall sensor making use of modern physical simulator. A 3D model of a squared Hall sensor in CMOS technology is implemented. Galvanic transport model is used for numerical simulation of magnetic force effects on silicon device. In order to correctly analyze the response time, Mixed-mode SPICE-physical simulations was performed on the whole circuit, i.e. 3D device plus biasing scheme. Simulations show a fast response time for the modeled device, enabling acquisition bandwidth in the MHz range. The settling time partially depends on incident magnetic field and biasing current, while it depends greatly on physical structure of the sensor. Doping concentration of the n-type well is one of the main parameters affecting time response. Faster Hall devices can be realized using higher concentrations of the n-well but this will significantly reduce the sensitivity of the sensor. To our knowledge, this paper is the first one attending to analysis of time limits in CMOS Hall sensors.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
