Description

The A1220, A1221, and A1222 Hall-effect sensor ICs are

extremely temperature-stable and stress-resistant devices

especiallysuitedforoperationoverextendedtemperatureranges

to 150°C. Superior high-temperature performance is made

possiblethroughdynamicoffsetcancellation,whichreducesthe

residual offset voltage normally caused by device overmolding,

temperature dependencies, and thermal stress. Each device

includesonasinglesiliconchipavoltageregulator,Hall-voltage

generator,small-signalamplifier,chopperstabilization,Schmitt

trigger, and a short-circuit protected open-collector 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 UAis a three-pin ultra-

mini SIP for through hole mounting. Both packages are lead

(Pb) free, with 100% matte tin plated leadframes.

A1220-DS, Rev. 8

Features and Benefits

▪ 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

Chopper Stabilized Precision Hall Effect Latches

Packages:

Functional Block Diagram

Not to scale

A1220, A1221, and A1222

3-pin SOT23W (suffix LH)

3-pin SIP (suffix UA)

Regulator

GND

VCC

VOUT

Control

Current Limit

To All Subcircuits

Amp

Low-Pass

Filter