Allegro a1301 continuous time ratiometric linear hall effect switch 2 5mv g allegro a1301eua t the a1301eua t is a continuous time ratiometric linear hall effect sensor that has been optimised to provide an accurate voltage output that is proportional to an applied magnetic field the sensor features a fast power on time and low noise output and integrates a hall circuit linear amplifier and a cmos class a output structure the ic comes in a through hole 3 pin sip case and is factory pro