A1250

A1250 Hall-Effect Latch / Bipolar Switch FEATURES AND BENEFITS AEC-Q100 automotive qualified High-speed, 4-phase chopper stabilization Low operating voltage down to 3 V High sensitivity Stable switchpoints Robust EMC Packages: 3-Pin SOT23W (suffix LH) 3-Pin SIP (suffix UA) Not to scale V+ VCC Regulator DESCRIPTION The A1250 Hall-effect sensor IC is a temperature-stable, stress-resistant bipolar switch. This device is the most sensitive Hall-effect device in theAllegro™ bipolar switch family and is intended for ring-magnet sensing. Superior high-temperature performance is made possible through an Allegro patented dynamic offset cancellation that utilizes chopper stabilization. This method reduces the offset voltage normally caused by device overmolding, temperature dependencies, and thermal stress. The A1250 includes the following on a single silicon chip: a voltage regulator, Hall-voltage generator, small-signal amplifier, chopper stabilization, Schmitt trigger, and a shortcircuit-protected open-drain output. Advanced BiCMOS wafer fabrication processing takes advantage of low-voltage requirements, component matching, very low input-offset errors, and small component geometries. The A1250 Hall-effect bipolar switch turns on in a south polarity magnetic field of sufficient strength and switches off in a north polarity magnetic field of sufficient strength. Because the output state is not defined if the magnetic field is diminished or removed, to ensure ...