Allegro Multimedia A1321 Benutzerhandbuch

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Description
The A132X family of linear Hall-effect sensors are optimized, 
sensitive, and temperature-stable. These ratiometric Hall-effect 
sensors provide a voltage output that is proportional to the 
applied magnetic field.  The A132X family has a quiescent 
output voltage that is 50% of the supply voltage and output 
sensitivity options of 2.5mV/G, 3.125mV/G, and 5mV/G. The 
features of this family of devices are ideal for use in the harsh 
environments found in automotive and industrial linear and 
rotary position sensing systems. 
Each device has a BiCMOS monolithic circuit which integrates 
a Hall element, improved temperature-compensating circuitry 
to reduce the intrinsic sensitivity drift of the Hall element, 
a small-signal high-gain amplifier, and a rail-to-rail low-
impedance output stage.
A proprietary dynamic offset cancellation technique, with 
an internal high-frequency clock, reduces the residual offset 
voltage normally caused by device overmolding, temperature 
dependencies, and thermal stress. The high frequency clock 
allows for a greater sampling rate, which results in higher 
accuracy and faster signal processing capability. This technique 
produces devices that have an extremely stable quiescent output 
voltage, are immune to mechanical stress, and have precise 
A1321-DS, Rev. 10
Features and Benefits
▪  Temperature-stable quiescent output voltage
▪  Precise recoverability after temperature cycling
▪  Output voltage proportional to magnetic flux density
▪  Ratiometric rail-to-rail output
▪ Improved 
sensitivity
▪  4.5 to 5.5 V operation
▪  Immunity to mechanical stress
▪ Solid-state 
reliability
▪  Robust EMC protection 
Ratiometric Linear Hall Effect Sensor 
for High-Temperature Operation 
Functional Block Diagram
Not to scale
Packages: 3 pin SOT23W (suffix LH), and 
3 pin SIP (suffix UA)
A1321, A1322, and A1323
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Amp
GND
VOUT
VCC
Out
Offset
Trim
Control
Gain
0.1
μF
V+
Dyna
mic
O
ffse
t
Ca
nce
lla
ti
on
Filte
r