AH182/AH183 is a three-terminal Hall effect sensor device with an output driver， mainly designed for battery–operation， hand-held equipment （such as cellular and cordless phones， and PDA’s） The total operation power is down to 15uW in the 2.75V supply. The south pole of sufficient strength will turn the output on in SIP-3L but the north pole of sufficient strength will turn the output on in SC59 package. The output will be turned off under no magnetic field. While the magnetic flux density （B） is larger than operation point （Bop）， the output will be turned on （low）， the output is held until B is lower than the release point （Brp）， then turned off. The difference between AH182 and AH183 is that the former consumes less power than that of the latter in the Hall sensor operation.