This part is a kind of semiconductor called UGN3177.

Function of this product has (UGN3175 / UGN3177) HALL-EFFECT LATCHES.

Manufacturers : Allegro MicroSystems

Image and pinout :

Some of the text within the PDF file :

3175 AND 3177 HALL-EFFECT LATCHES These Hall-effect latches are temperature-stable and stress-resistant sensors especially suited for electronic commutation in brushless dc motors using multipole ring magnets. Each device includes a voltage regulator, quadratic Hall voltage generator, temperature compensation circuit, signal amplifier, Schmitt trigger, and an open-collector output on a single silicon chip. The on-board regulator permits operation with supply voltages of 4.5 volts to 18 volts. The switch output can sink 10 mA. With suitable output pull up, they can be used directly with bipolar or MOS logic circuits. The three package styles available provide a magnetically optimized package for most applications. Suffix ‘LT’ is a surface-mount SOT-89/ TO-243AA package; suffixes ‘U�� [ ... ]

UGN3177 PDF Datasheet Download