This part is a kind of semiconductor called A3150.

Function of this product has PROGRAMMABLE/ CHOPPERSTABILIZED/ HALL-EFFECT SWITCH.

Manufacturers : Allegro MicroSystems

Image and pinout :

Some of the text within the PDF file :

3150 PROGRAMMABLE, CHOPPERSTABILIZED, HALL-EFFECT SWITCH The A3150JLT and A3150JUA programmable switches provide tooth/valley recognition in large gear-tooth sensing applications. Each sensor consists of a single element, chopper-stabilized Hall-effect IC that can be programmed to the desired magnetic switch point, optimizing sensor airgap and timing accuracy performance after final packaging. The small package can be easily assembled and used in conjunction with a wide variety of gear/target shapes and sizes. The two devices differ only in package style. The sensing technology used for this sensor is Hall-effect based. The sensor incorporates a single-element Hall IC that switches in response to magnetic signals created by a ferrous target. The programmability of the circuit eliminates m [ ... ]

A3150 PDF Datasheet Download