A119 Datasheet, PDF (1/22 Pages) Allegro MicroSystems – Programmable, Chopper-Stabilized, Two-Wire Hall-Effect Switches

A119x and A119x-F
Programmable, Chopper-Stabilized, Two-Wire Hall-Effect Switches
FEATURES AND BENEFITS
▪ Choice of factory-set temperature coefficient (TC) for use
with ferrite or rare-earth magnets
▪ Field programmable for optimized switchpoints
▪ AEC-Q100 automotive qualified
▫ On-board voltage regulator: 3 to 24 V operation
▪ High-speed, 4-phase chopper stabilization
▫ Low switchpoint drift throughout temperature range
▫ Low sensitivity to thermal and mechanical stresses
▪ On-chip protection
▫ Supply transient protection
▫ Reverse-battery protection
▫ Industry-leading ISO 7637-2 performance through use of
proprietary, 40 V clamping structure
▪ Solid-state reliability
▪ Robust EMC and ESD performance
▪ UB package with integrated 0.1 µF bypass capacitor
Packages
3-pin SOT23-W
2 mm × 3 mm × 1
mm (suffix LH)
3-pin ultramini SIP
1.5 mm × 4 mm × 3
mm (suffix UA)
2-pin ultramini SIP
1.5 mm × 4 mm × 4
mm (suffix UB)
Not to scale
DESCRIPTION
The A119x and A119x-F comprise a family of two-wire,
unipolar, Hall-effect switches, which can be trimmed by the
user at end-of-line to optimize magnetic switchpoint accuracy
in the application. The latter (-F option) are temperature-
compensated for use with ferrite magnets. These devices are
produced on theAllegro^™ advanced BiCMOS wafer fabrication
process, which implements a patented high-frequency, 4-phase,
chopper stabilization technique. This technique achieves
magnetic stability over the full operating temperature range,
and eliminates offsets inherent in devices with a single Hall
element that are exposed to harsh application environments.
The A119x and A119x-F family has a number of automotive
applications. These include sensing seat track position, seat belt
buckle presence, hood/trunk latching, and shift selector position.
Two-wire unipolar switches are particularly advantageous in
cost-sensitive applications because they require one less wire
for operation versus the more traditional open-collector output
switches. Additionally, the system designer inherently gains
diagnostics 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 condition.
All family members are offered in three package styles. The LH
is a SOT-23W style, miniature, low-profile package for surface-
mount applications. The UA is a 3-pin, ultra-mini, single inline
package (SIP) for through-hole mounting. The UB is a 2-pin single
inline package (SIP) for through-hole mounting that integrates
the power supply decoupling capacitor. All three packages are
lead (Pb) free, with 100% matte-tin leadframe plating.
UB package only
V+ VCC
LH & UA
package
only
0.01 µF
0.1 µF
Regulator
To all subcircuits
Clock/Logic
Program / Lock
Offset Adjust
I_CC Adjust
Amp
Polarity
Low-Pass
Filter
Schmitt
Trigger
A1190-DS, Rev. 7
GND
GND
Functional Block Diagram
UA package only