This part is a kind of semiconductor called AH3503.

Function of this product has LINEAR HALL-EFFECT SENSOR.

Manufacturers : NANJING AH ELECTRONICS

Image and pinout :

Some of the text within the PDF file :

NANJING AH ELECTRONICS CO., LTD AH3503 SERIES LINEAR HALL-EFFECT SENSOR Integrated circuit includes a voltage regulator, Hall-voltage generator, linear amplifier and emitter-follower out stage. The output of the Ics change linearity with the magnetic flux density of the input. FEATURES . Extremely Sensitive . Flat response to 23kHz . Low-Noise Output . 4.5V to 6V Operation . Magnetically Optimized Package TYPICAL APPLICATION . Motion detector . Gear tooth sensors . Proximity detector . Velocity detecting of motor bicycle . Current detecting sensor ABSOLUTE MAXIMUM RATINGS Parameter Symbol Supply voltage Vcc Magnetic flux density B Operating temperature range TA Storage temperature range TS Value 6 不限 -20~+85 150 Unit V mT ℃ ℃ ELECTRICAL CHARACTERISTICS TA=25℃ [ ... ]

AH3503 PDF Datasheet Download