A1220_16 Datasheet, PDF (1/16 Pages) Allegro MicroSystems – Chopper-Stabilized Precision Hall-Effect Latches

A1220, A1221, A1222, and A1223
Chopper-Stabilized Precision Hall-Effect Latches
Features and Benefits
▪ AEC-Q100 automotive qualified
▪ Symmetrical latch switchpoints
▪ Resistant to physical stress
▪ Superior temperature stability
▪ Output short-circuit protection
▪ Operation from unregulated supply down to 3 V
▪ Reverse-battery protection
▪ Solid-state reliability
▪ Small package sizes
Packages:
Not to scale
3-pin SOT23W
(suffix LH)
(A1220
and 1221)
(A1222
and A1223)
3-pin SIP (suffix UA)
Description
The A1220, A1221, A1222, and A1223 Hall-effect sensor ICs
are extremely temperature-stable and stress-resistant devices
especially suited for operation over extended temperature ranges
to 150°C. Superior high-temperature performance is made
possible through dynamic offset cancellation, which reduces the
residual offset voltage normally caused by device overmolding,
temperature dependencies, and thermal stress. Each device
includes on a single silicon chip a voltage regulator, Hall-
voltage generator, small-signal amplifier, chopper stabilization,
Schmitt trigger, and a short-circuit protected open-drain output
to sink up to 25 mA. A south pole of sufficient strength turns
the output on. A north pole of sufficient strength is necessary
to turn the output off.
An onboard regulator permits operation with supply voltages
of 3 to 24 V. The advantage of operating down to 3 V is that
the device can be used in 3 V applications or with additional
external resistance in series with the supply pin for greater
protection against high voltage transient events.
Two package styles provide magnetically optimized packages
for most applications. Package type LH is a modified 3-pin
SOT23W surface-mount package, while UA is a three-pin
ultra-mini SIP for through-hole mounting. Both packages are
lead (Pb) free, with 100% matte-tin-plated leadframes.
Functional Block Diagram
VCC
Amp
Regulator
Low-Pass
Filter
To All Subcircuits
Control
Current Limit
VOUT
GND
A1220-DS, Rev. 16