a
FEATURES
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 V
CC
APPLICATIONS
Automotive
Throttle Position Sensing
Pedal Position Sensing
Suspension Position Sensing
Valve Position Sensing
Industrial
Absolute Position Sensing
Proximity Sensing
GENERAL DESCRIPTION
Linear Output
Magnetic Field Sensor
AD22151
FUNCTIONAL BLOCK DIAGRAM
REF
V
CC
/2
TEMP REF
OUT AMP
AD22151
I
SOURCE
SWITCHES
DEMOD
V
CC
NC
R1
R2
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.
Principle features include dynamic offset drift cancellation and a
built-in temperature sensor. Designed for single +5 volt supply
operation, the AD22151 achieves low drift offset and gain op-
eration over 鈥?0擄C to +150擄C. Temperature compensation can
accommodate a number of magnetic materials commonly uti-
lized in economic position sensor assemblies.
The transducer may be configured for specific signal gains de-
pendent upon 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 sig-
nal is ratiometric to the positive supply rail in all configurations.
GND
0.1 F
R3
OUTPUT
NC = NO CONNECT
AD22151
Figure 1. Typical Bipolar Configuration with Low
(< 鈥?00 ppm) Compensation
V
CC
R1
R4
NC
R2
0.1 F
R3
OUTPUT
GND
NC = NO CONNECT
AD22151
Figure 2. Typical Unipolar Configuration with High
(鈮?/div>
鈥?000 ppm) Compensation
REV. 0
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
漏 Analog Devices, Inc., 1997
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