A1374LKB Allegro Microsystems Inc, A1374LKB Datasheet - Page 13

• Manufacturer Part Number: A1374LKB
• Description: IC SENSOR HALL EFFECT PREC 3-SIP
• Manufacturer: Allegro Microsystems Inc
• Type: Bipolar or Unipolar, Programmabler

Specifications of A1374LKB

• Sensing Range: 1.75mV/G ~ 11.25mV/G
• Voltage - Supply: 4.5 V ~ 5.5 V
• Current - Supply: 10mA
• Current - Output (max): 10mA
• Output Type: Analog, Ratiometric
• Features: High Precision
• Operating Temperature: -40°C ~ 150°C
• Package / Case: 3-SIP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

A1373
A1374
Chopper Stabilization Technique
Chopper stabilization is a unique approach used to minimize
Hall offset on the chip. The patented Allegro technique, namely
Dynamic Quadrature Offset Cancellation, removes key sources
of the output drift induced by thermal and mechanical stresses.
This offset reduction technique is based on a signal modulation-
demodulation process. The undesired offset signal is separated
from the magnetic field-induced signal in the frequency domain,
through modulation.
The subsequent demodulation acts as a modulation process for
the offset, causing the magnetic field-induced signal to recover
its original spectrum at baseband, while the dc offset becomes
a high-frequency signal. The magnetic-sourced signal then can
and
Hall Element
Concept of Chopper Stabilization Technique
Regulator
High Precision, Output Pin Programmable
pass through a low-pass filter, while the modulated dc offset is
suppressed.
The chopper stabilization technique uses a 200 kHz high
frequency clock. For demodulation process, a sample and hold
technique is used, where the sampling is performed at twice the
chopper frequency (400 kHz). This high-frequency operation
allows a greater sampling rate, which results in higher accuracy
and faster signal-processing capability.
This approach desensitizes the chip to the effects of thermal and
mechanical stresses, and produces devices that have extremely
stable quiescent Hall output voltages and precise recoverability
after temperature cycling. This technique is made possible
through the use of a BiCMOS process, which allows the use of
low-offset, low-noise amplifiers in combination with high-den-
sity logic integration and sample-and-hold circuits.
Linear Hall Effect Sensor ICs
Clock/Logic
Amp
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
Low-Pass
Filter
12