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A3212ELHLT-T

A3212ELHLT-T

Allegro MicroSystems
Digital Switch Omnipolar Switch Open Drain Hall Effect SOT-23W
Active39,107 in stock
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Overview

The Allegro A3212ELHLT-T is a micropower, omnipolar Hall-effect switch designed for battery-operated, hand-held equipment. It detects both North and South magnetic poles and provides a digital open-drain output. Its low power consumption and robust design make it suitable for various portable applications.

Why Choose This Part

This omnipolar Hall-effect switch offers significant advantages with its micropower operation (8 uA sleep current, 2.0mA run current), extending battery life in portable devices. Its chopper-stabilized design ensures superior temperature stability and extremely low switch point drift, providing reliable performance across a -40degC to 85degC operating range. The AEC-Q100 qualification also makes it suitable for demanding automotive applications.

Applications

Battery-operated, Hand-held Equipment
Ideal for detecting cover open/close or button presses in portable devices due to its micropower operation and omnipolar sensing.
Cellular and Cordless Telephones
Used for flip-phone lid detection or other user interface sensing where low power and a compact form factor are critical.
Pagers and Palmtop Computers
Provides reliable magnetic sensing for various functions in older portable electronic devices.
Automotive Position Sensing
The AEC-Q100 qualification makes it suitable for non-safety-critical position sensing in automotive environments, such as door or seatbelt buckles, within its operating temperature range of -40degC to 85degC.
Home Appliances
Can be used in appliance interfaces or safety interlocks requiring magnetic field detection with low power consumption.

Key Specifications

Function Omnipolar Switch
Technology Hall Effect
Output Type Open Drain
Polarization North Pole, South Pole
Mounting Type Surface Mount
Sensing Range +/-5.5mT Trip, +/-1mT Release
Package / Case SOT-23W
Test Condition -40degC ~ 85degC
Voltage - Supply 2.5V ~ 3.5V
Operating Temperature -40degC ~ 85degC (TA)
Current - Output (Max) 1mA
Current - Supply (Max) 2mA
Supplier Device Package SOT-23W

Getting Started

To get started with the A3212ELHLT-T, integrate it into your low-voltage (2.5V to 3.5V) circuit, connecting the open-drain output to a pull-up resistor and then to a microcontroller input. The output will switch low when a magnetic field of +/-5.5mT (trip) is detected. Ensure proper decoupling capacitance on the supply pin and consider the SOT-23W package for surface-mount designs.

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