A1148LUA
| Model | A1148LUA |
| Description | Low Current Ultrasensitive Two-Wire Chopper-Stabilized Unipolar Hall Effect Switches |
| PDF file | Total 13 pages (File size: 320K) |
| Chip Manufacturer | ALLEGRO |
A1147 and A1148
Low Current Ultrasensitive Two-Wire Chopper-Stabilized
Unipolar Hall Effect Switches
The A1147 and A1148 devices are two-wire, unipolar, Hall effect switches that are
factory-programmed at end-of-line to optimize ultrasensitive magnetic switchpoint
accuracy. These devices use a patented high frequency chopper-stabilization tech-
nique, produced using the Allegro advanced BiCMOS wafer fabrication process,
to achieve magnetic stability and to eliminate offset inherent in single-element
devices exposed to harsh application environments.
≈1:1
Package LH, 3-pin SOT
Package UA, 3-pin SIP
Commonly found in a number of automotive applications, these switches are
utilized to sense seat track position, seat belt buckle presence, hood/trunk latch-
ing, and shift selector position. Two-wire unipolar switches, such as the A1147
and A1148, are particularly advantageous in price-sensitive applications because
they require one less wire for operation than do switches with the more traditional
open-collector output. Additionally, the system designer inherently gains diagnos-
tics because there is always output current flowing, which should be in either of
two narrow ranges. Any current level not within these ranges indicates a fault con-
dition. These devices also feature on-chip transient protection and a Zener clamp
to protect against overvoltage conditions on the supply line.
The output currents of the A1148 switches HIGH in the presence of a south (+)
polarity magnetic field of sufficient strength, and switches LOW otherwise, as in
the presence of a weak field or a north (–) polarity field. The A1147 has an oppo-
site output: the currents switch LOW in the presence of a south-polarity magnetic
field of sufficient strength, and switch HIGH otherwise.
Both versions are offered in two package styles. The LH is a SOT-23W, miniature
low-profile package for surface-mount applications. The UA is a three-lead ultra-
mini SIP for through-hole mounting. Each package is available in a lead (Pb) free
version (suffix,
–T)
with 100% matte tin plated leadframe. Field-programmable
versions also available: A1180 and A1181.
≈1:1
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, V
CC
..........................................
28 V
Reverse-Supply Voltage, V
RCC
........................
–18 V
Magnetic Flux Density, B .........................Unlimited
Power Dissipation, P
D
............................
Graph, p. 5
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
Features and Benefits
Chopper stabilization
Low switchpoint drift over operating
temperature range
Low sensitivity to stress
Factory programmed at end-of-line for
optimized switchpoints
On-chip protection
Supply transient protection
Reverse-battery protection
On-board voltage regulator
3.5 to 24 V operation
A1147-DS, Rev. 6
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
Related PDFs
| Model | Description | Manufacturer | Operation |
|---|---|---|---|
 A1148LUA-T
|
Low Current Ultrasensitive Two-Wire Chopper-Stabilized Unipolar Hall Effect Switches | ALLEGRO | Preview |
|
A1148LUATI
|
Low Current Ultrasensitive Two-Wire Chopper-Stabilized Unipolar Hall Effect Switches | ALLEGRO | Preview |
|
A1148LUATI-T
|
Low Current Ultrasensitive Two-Wire Chopper-Stabilized Unipolar Hall Effect Switches | ALLEGRO | Preview |
