鈻?/div>
High ESD ratings (HBM)
Description
The A3245 integrated circuit is an omnipolar, ultrasensitive
Hall-effect switch with a digital output. This sensor has an
integrated regulator permitting operation to 24 V, making it
the first omnipolar switch available for operation to 24 V.
This device is especially suited for operation over extended
temperature ranges, up to +150擄C. Superior high-temperature
performance is made possible through an Allegro
廬
patented
dynamic offset cancellation, which reduces the residual offset
voltage normally caused by device overmolding, temperature
excursions, and thermal stress.
The A3245 Hall-effect switch includes the following on a single
silicon chip: voltage regulator, Hall-voltage generator, small-
signal amplifier, chopper stabilization, Schmitt trigger, and a
short circuit protected open-drain output. Advanced BiCMOS
wafer fabrication processing is used to take advantage of low-
voltage requirements, component matching, very low input-
offset errors, and small component geometries.
The omnipolar operation of the A3245 allows activation with
either a north
or
a south polarity field of sufficient strength. In
the absence of a magnetic field, the output is off. This patented
Packages: 3 pin SOT23W (suffix LH), and
3 pin SIP (suffix UA)
Continued on the next page鈥?/div>
Not to scale
Functional Block Diagram
VCC
Regulator
To All Subcircuits
Sample and Hold
Dynamic Offset
Cancellation
Low-Pass
Filter
VOUT
Amp
Amp
Control
Current Limit
<1惟
GND
A3245-DS, Rev. 2
next