Low current Hall Effect Sensor

Abstract

Many modern electronic devices utilize linear Hall sensors to measure current and the magnetic field, as well as to perform switching and latching operations. Smartphones, laptops, and e-readers all work with very low (sub-mA) currents. To perform a switching function in such low-power devices, however, a Hall sensor must be able to work in the {\mu}A regime. This paper demonstrates, for the first time, the ability of a standard Hall detector to work in the {\mu}A regime between 0 and 0.7 Tesla. A second important application of this technology is the measurement of electron transport parameters in thin films, which is essential to elucidating their electronic behavior. The development of new devices using thin films demands very precise measurements of tiny electrical currents, low-intensity magnetic fields, and other small signals. The proposed system delivers a very small but stable electric current without external noise, and can be used to measure small transport parameters with very high precision. We demonstrate the capabilities of this system by measuring the slope of the Hall effect with a four-point probe at current intensities of 100, 10, and 1 {\mu}A.