This part is a kind of semiconductor called A1145.

Function of this product has (A1145 / A1146) Ultrasensitive Two-Wire Chopper-Stabilized Unipolar Hall Effect Switches.

Manufacturers : Allegro MicroSystems

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A1145 and A1146 Ultrasensitive Two-Wire Chopper-Stabilized Unipolar Hall Effect Switches Features and Benefits ▪ Chopper stabilization ▫ Low switchpoint drift over operating temperature range ▫ Low sensitivity to stress ▪ Factory programmed at end-of-line for optimized switchpoints ▪ On-chip protection ▫ Supply transient protection ▫ Reverse-battery protection ▫ On-board voltage regulator ▫ 3.5 to 24 V operation Description The A1145 and A1146 devices are two-wire, unipolar, Hall effect switches that are factory-programmed at end-of-line to optimize ultrasensitive magnetic switchpoint accuracy. These devices use a patented high frequency chopper-stabilization technique, produced using the Allegro advanced BiCMOS wafer fabrication process, to achieve magnetic stability a [ ... ]

A1145 PDF Datasheet Download