Description

The A1180, A1181, A1182, and A1183 devices are sensitive,

can be field-programmed, after final packaging of the sensor

and placement into the application. This advanced feature

allows the optimization of the sensor switching performance,

by effectively accounting for variations caused by mounting

tolerances for the device and the target magnet.

This family of devices are produced on the Allegro

MicroSystems advanced BiCMOS wafer fabrication process,

which implements a patented, high-frequency, chopper-

stabilization technique that achieves magnetic stability and

eliminates the offsets that are inherent in single-element devices

exposed to harsh application environments. Commonly found

in a number of automotive applications, theA1180-83 family of

devices are utilized to sense: seat track position, seat belt buckle

presence, hood/trunk latching, and shift selector position.

Two-wire unipolar switches are particularly advantageous

in price-sensitive applications, because they require one

less wire than the more traditional open-collector output

A1180-DS, Rev. 5

Features and Benefits

▪ Chopper stabilization

▫ Low switchpoint drift over operating

temperature range

▫ Low sensitivity to stress

▪ Field programmable for optimized switchpoints

▪ On-chip protection

▫ Supply transient protection

▫ Reverse-battery protection

▫ On-board voltage regulator

▫ 3.5 to 24 V operation

Sensitive Two-Wire Field-Programmable Chopper-Stabilized

Unipolar Hall-Effect Switches

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Functional Block Diagram

Not to scale

Packages: 3 pin SOT23W (suffix LH), and

3 pin SIP (suffix UA)

A1180, A1181, A1182, and A1183

Amp

Regulator

Low-Pass

Filter

GND

VCC

GND

Package UA Only

0.01 uF

V+

Program/Lock

Programming

Logic

Offset

Clock/Logic