A3290 and A3291
Chopper Stabilized, Precision Hall Effect Latches for
Consumer and Industrial Applications
Features and Benefits
Description
▪ Symmetrical switchpoints
▪ Resistant to physical stress
▪ Superior temperature stability
▪ Output short-circuit protection
▪ Operation from unregulated supply
▪ Reverse battery protection
▪ Solid-state reliability
The A3290 and A3291 Hall effect latches are extremely
temperature-stable and stress-resistant sensors, especially
suited for operation over extended temperature ranges (up
to 125°C). Superior high-temperature performance is made
possible through Dynamic Offset Cancellation, which reduces
the residual offset voltage normally caused by device package
overmolding,temperaturedependencies,andthermalstress.The
twodevicesareidenticalexceptfortheirmagneticswitchpoints.
They are not intended for automotive applications.
▪ Small package size
Bothdevicesinclude,onasinglesiliconchip,avoltageregulator,
a Hall-voltage generator, a small-signal amplifier, chopper
stabilization, a Schmitt trigger, and a short-circuit protected
open-collector output to sink up to 25 mA. A south polarity
magneticfieldofsufficientstrengthisrequiredtoturntheoutput
on. A north polarity field of sufficient strength is necessary to
turn the output off. An onboard regulator permits operation
with supply voltages in the range of 4.2 to 24 volts.
Packages: 3 pin SOT23W (suffix LH), and
3 pin SIP (suffix UA)
Twopackagestylesprovideamagneticallyoptimizedpackage
for most applications. Type LH is a miniature SOT23W low-
profile surface-mount package, and type UA is a three-pin
ultramini SIP for through-hole mounting. Both packages are
lead (Pb) free with 100% matte tin leadframe plating.
Not to scale
Functional Block Diagram
VCC
Regulator
OUT
Low-Pass
Filter
Amp
Control
Current Limit
17
GND
A3290-DS