AG920-07 NVE, AG920-07 Datasheet - Page 126

• Manufacturer Part Number: AG920-07
• Description: KIT EVALUATION GT SENSOR
• Manufacturer: NVE

Specifications of AG920-07

• Sensor Type: Magnetic. GMR (Giant Magnetoresistive)
• Interface: Analog
• Embedded: No
• Utilized Ic / Part: ABL & AKL Series GT Sensors
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Voltage - Supply: -
• Sensitivity: -
• Sensing Range: -
• Other names: 391-1022

Magnetic Media Detection
General discussion
GMR Magnetic Field Sensors can be used for detecting different types of magnetic media. In this
situation, NVE defines magnetic media as material that has a distinct magnetic signature. The media is
typically a non-magnetic substrate with magnetic material placed in or on the substrate. Typically,
GMR sensors are used to “read” the magnetic signature by sweeping the substrate and the sensor past
each other.
Depending upon the application, the magnetic parts of the substrate can be detected indirectly by
sensing a perturbation of an externally applied field or sensed directly due to the part’s own field. The
output of the sensor will be a function of: (1) the magnetic properties of the media; (2) the working
gap; and (3) the type of sensor used.
Application examples
Basic concepts
For applications in which minimum size is not critical, external flux concentrators can be used to
increase sensor sensitivity. These external flux concentrators function in the same manner as the flux
concentrators within the sensor.
Elongated pieces of soft magnetic material gather external magnetic flux and expose the sensor to a
magnetic field that is larger than the external magnetic field. For best results, two pieces of soft
magnetic material of the same size are used. The concentration factor is approximately the ratio of one
• Magnetic ink detection
• Magnetic stripe reading
• Fine magnetic particle detection
• Media magnetic signature detection
• Magnetic anomaly detection in substrates
External flux concentrator
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Axis of Sensitivity
AAxxx-xx
NVE
L gap
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External flux concentrator
Flux concentration factor:
FC ~ L concentrator/L gap
L concentrator
Application Notes