AG920-07E NVE, AG920-07E Datasheet - Page 6

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

Specifications of AG920-07E

• Sensor Type: Magnetic. GMR (Giant Magnetoresistive)
• Interface: Analog
• Embedded: No
• Utilized Ic / Part: ABL & AKL Series GT Sensors
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Supply: -
• Sensitivity: -
• Sensing Range: -
• Other names: 391-1063

NVE’s GMR materials are noteworthy in comparison with other GMR material types in that NVE’s
material cannot be damaged with the application of extremely large magnetic fields. GMR materials
from other sources often rely on keeping one of the magnetic layers internally magnetized, or pinned,
in a specific direction, and allowing the other layer to rotate and thus provide the GMR effect. In some
of these materials, an external magnetic field as small as 200 Gauss can upset this pinned layer, thus
permanently damaging the sensor element. Most of NVE’s GMR materials rely on anti-ferromagnetic
coupling between the layers; as a result they are not affected by extremely large fields, and will resume
normal operation after the large field is removed. NVE has recently introduced a production GMR
material with a pinned magnetic layer, this pinned layer uses a synthetic anti-ferromagnet for the
pinning, which cannot be upset at temperatures below 300ºC. As a result, NVE’s pinned GMR material
is not susceptible to upset problems.
The following chart shows a typical characteristic for NVE’s standard multilayer GMR material:
The material shown in the plot is used in most of NVE’s GMR sensor products. It provides a 98%
linear output from 10% to 70% of full scale, a large GMR effect (13% to 16%), a stable temperature
coefficient (0.14%/°C) and temperature tolerance (+150°C), and a large magnetic field range (0 to
±300 Gauss).
In addition to manufacturing this excellent GMR material, NVE is constantly developing new GMR
materials. New products have recently been introduced which use three new materials: one with double
the magnetic sensitivity of the standard material, one with half the magnetic hysteresis, and one with a
synthetic antiferromagnet pinned layer designed for use in magnetic saturation. Some of these new
materials are suitable for operation to +225°C. Please see the application notes section of this catalog
for a complete description of the GMR material types available in NVE’s magnetic sensors.
NVE continues to lead the market in GMR-based magnetic sensors due to constant emphasis on
developing new or improved GMR materials and frequent new product releases utilizing these
improvements.
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-500
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Applie d Ma gnetic Fie ld (Gauss)
www.nve.com
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phone: [phone] fax: [phone]
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Notice that the output characteristic is
omnipolar, meaning that the material provides
the same change in resistance for a
directionally positive magnetic field as it does
for a directionally negative field. This
characteristic has advantages in certain
applications.
For example, when used on a magnetic
encoder wheel, a GMR sensor using this
material will provide a complete sine wave
output for each pole on the encoder (rather
than each pole pair, as with a Hall Effect
sensor), thus doubling the resolution of the
output signal.
Introduction