Magnetic Field Sensor
Adjustable Offset to Unipolar or Bipolar Operation
Low Offset Drift over Temperature Range
Gain Adjustable over Wide Range
Low Gain Drift over Temperature Range
Adjustable First Order Temperature Compensation
Ratiometric to VCC
Throttle Position Sensing
Pedal Position Sensing
Suspension Position Sensing
Valve Position Sensing
Absolute Position Sensing
The AD22151 is a linear magnetic field transducer. The sensor
output is a voltage proportional to a magnetic field applied
perpendicularly to the package top surface.
The sensor combines integrated bulk Hall cell technology and
instrumentation circuitry to minimize temperature related drifts
associated with silicon Hall cell characteristics. The architecture
maximizes the advantages of a monolithic implementation while
allowing sufficient versatility to meet varied application require-
ments with a minimum number of components.
Principal features include dynamic offset drift cancellation
and a built-in temperature sensor. Designed for single 5 V
supply operation, the AD22151 achieves low drift offset and
gain operation over –40∞C to +150∞C. Temperature compensa-
tion can accommodate a number of magnetic materials commonly
utilized in economic position sensor assemblies.
The transducer can be configured for specific signal gains to
meet various application requirements. Output voltage can be
adjusted from fully bipolar (reversible) field operation to fully
unipolar field sensing.
The voltage output achieves near rail-to-rail dynamic range,
capable of supplying 1 mA into large capacitive loads. The
signal is ratiometric to the positive supply rail in all configurations.
FUNCTIONAL BLOCK DIAGRAM
NC = NO CONNECT
Figure 1. Typical Bipolar Configuration with Low
(< –500 ppm) Compensation
NC = NO CONNECT
Figure 2. Typical Unipolar Configuration with
High (Ϸ –2000 ppm) Compensation
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