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A1180/81/82/83
A1180-DS, Rev. 2
Worcester, Massachusetts 01615-0036 (508) 853-5000
115 Northeast Cutoff, Box 15036
www.allegromicro.com
Allegro MicroSystems, Inc.
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VCC ..........................................28 V
Reverse-Supply Voltage, VRCC ........................–18 V
Magnetic Flux Density, B .........................Unlimited
Operating Temperature
Ambient, TA, Range E..................–40C to 85C
Ambient, TA, Range L................–40C to 150C
Maximum Junction, TJ(max)........................165C
Storage Temperature, TS ..................–65C to 170C
On-chip protection
Supply transient protection
Reverse-battery protection
On-board voltage regulator
3.5 V to 24 V operation
Sensitive Two-Wire Field-Programmable Chopper-Stabilized
Unipolar Hall-Effect Switches
Package LH, 3-pin SOT
Features and Benets
1. VCC
2. No connection
3. GND
NC
1
2
3
1
2
3
1. VCC
2. GND
3. GND
Package UA, 3-pin SIP
Chopper stabilization
Low switchpoint drift over operating
temperature range
Low stress sensitivity
Field-programmable for optimized
switchpoints
The A1180, A1181, A1182, and A1183 devices are sensitive, two-wire, unipolar,
Hall effect switches. The operate point, BOP, can be eld-programmed, after nal
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 applica-
tion environments. Commonly found in a number of automotive applications,
the A1180-83 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 appli-
cations, because they require one less wire than the more traditional open-collec-
tor output switches. Additionally, the system designer gains inherent diagnostics
because output current normally ows in either of two narrowly-specied ranges.
Any output current level outside of these two ranges is a fault condition. The
A1180-83 family of devices also features on-chip transient protection, and a Zener
clamp to protect against overvoltage conditions on the supply line.
The output currents of the A1181 and A1183 switch HIGH in the presence of a south
polarity magnetic eld of sufcient strength; and switch LOW otherwise, including
when there is no signicant magnetic eld present. The A1180 and A1182 have
inverted output current levels: switching LOW in the presence of a south polarity
magnetic eld of sufcient strength, and HIGH otherwise. The devices also differ in
their specied LOW current supply levels.
Both devices are offered in two package styles: LH, a SOT-23W miniature low-
prole package for surface-mount applications, and UA, a three-lead ultramini
Single Inline Package (SIP) for through-hole mounting. Each package is available
in a lead (Pb) free version (sufx, –T) with 100% matte tin plated leadframe.
Factory-programmed versions are also available. Refer to: A1140, A1141, A1142,
A1143, A1145, and A1146.