Allegro MicroSystems recommends APS11500 for all new Automotive 2-wire Hall-Effect switch IC designs.
The A1150, A1152, A1153, A1155, A1156, A1157, and A1158
comprise a family of two-wire, unipolar, Hall-effect switches,
which are factory-trimmed to optimize magnetic switchpoint
accuracy. These devices are produced on the Allegro™ 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 A115x 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, ultra-mini, single inline package (SIP) for through-hole
mounting. All three packages are lead (Pb) free, with 100%
matte tin leadframe plating.
