As the strength of magnetic field(flux density) reaches Operation flux density(Bop), the output changes from High to Low. To prevent mis-operation(Chattering) around detected magnetic field, Brp is set to be smaller than Bop. The difference between Bop and Brp is called "Hysterisis."
As our Hall IC applies the Intermittent operation for lower power consumptions, Current consumption max out only at the sensing operation and stand-by for all the rest. Therefore, the current consumption is the entire operation average.
It detects magnetic field on Bipolar detection, and output changes from H to L and it reverts back to H as the magnetic field goes away. On the other hand, Bipolar Latch Hall IC(Track ball) detects changes on polarity of magnetic field. The output becomes High by detecting N-pole and latch, and the output becomes Low by detecting S-pole.