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.
AB SO LUTE MAX I MUM RAT INGS
Supply Voltage, V
CC
..........................................28 V
Reverse-Supply Voltage, V
RCC
........................–18 V
Magnetic Flux Density, B .........................Unlimited
Operating Temperature
Ambient, T
A
, Range E..................–40ºC to 85ºC
Ambient, T
A
, Range L................–40ºC to 150ºC
Maximum Junction, T
J(max)
........................165ºC
Storage Temperature, T
S
..................–65ºC to 170ºC
On-chip protection
null Supply transient protection
null Reverse-battery protection
null On-board voltage regulator
null 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 Benefi ts
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
null Low switchpoint drift over operating
temperature range
null 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, B
OP
, can be fi eld-programmed, after fi 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 fl ows in either of two narrowly-specifi ed 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 fi eld of suffi cient strength; and switch LOW otherwise, including
when there is no signifi cant magnetic fi eld present. The A1180 and A1182 have
inverted output current levels: switching LOW in the presence of a south polarity
magnetic fi eld of suffi cient strength, and HIGH otherwise. The devices also differ in
their specifi ed LOW current supply levels.
Both devices are offered in two package styles: LH, a SOT-23W miniature low-
profi le 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 (suffi x, –T) with 100% matte tin plated leadframe.
Factory-programmed versions are also available. Refer to: A1140, A1141, A1142,
A1143, A1145, and A1146.