How susceptible are the ACS712 and ACS713 to stray magnetic fields?
Assumptions for subsequent analysis: A. The stray field results from a current flowing through a printed circuit board (PCB) trace , or an external current-carrying conductor, adjacent to the Allegro device. B. The external current-carrying conductor is on the same plane as the Hall element. C. The conductor has an infinite length. The assumptions above provide a worst case analysis for stray field generated by the current-carrying conductor because there is no shielding of the Hall element, and the Hall element is in the optimum plane relative to the disturbance. The magnetic field, B, generated in the direction perpendicular to the plane in which the conductor and the Hall element lie, at the distance λ to the conductor, will be: BEXT = μ0 × I / ( 2 π × λ ) (tesla), where: μ0 = 4 π×10E-7 (H/m), = 400 π (nH/m), and assuming no core material around; I is in amperes, and is the magnitude of the current flowing in the conductor; and λ is in meters, and is the distance between the point u
