AG001-01 NVE, AG001-01 Datasheet - Page 7

• Manufacturer Part Number: AG001-01
• Description: KIT ENGINEERING EVALUATION
• Manufacturer: NVE

Specifications of AG001-01

• Rohs Status: RoHS non-compliant
• Sensor Type: Magnetic. GMR (Giant Magnetoresistive)
• Interface: Analog
• Embedded: No
• Utilized Ic / Part: AA & AB Series Analog Sensors
• Voltage - Supply: -
• Sensitivity: -
• Sensing Range: -
• Other names: 391-1003

Basic Sensor Design
NVE manufactures three basic sensor element types: magnetometers, which detect the strength of the
applied magnetic field, gradiometers (or differential sensors), which detect the difference in the applied
magnetic field strength at two discrete points on the sensor element, and spin valve sensors, which
change in output with the angular difference between the pinned layer and the free layer of the GMR
material while the device is exposed to a saturating magnetic field.
These three basic sensor element types are described in the sections below.
Magnetometers
NVE’s magnetometers are covered by our basic GMR material and sensor structure patents and have
unique features designed to take advantage of the characteristics of GMR sensor materials. A
photomicrograph of an NVE sensor element is shown below:
The size of this IC is approximately 350 microns by 1400 microns. The sensor is configured as a
Wheatstone bridge. The serpentine structures in the center of the die and to the left of center under the
large plated structure are 5 kΩ resistors made of GMR material.
The two large plated structures shown on the die are flux concentrators. They serve two purposes.
First, notice that they cover two of the resistors in the Wheatstone bridge. In this configuration the flux
concentrators function as a shield for these two resistors, preventing an applied magnetic field from
reaching them. Therefore, when a field is applied, the two GMR resistors in the center of the die
decrease in resistance, while the two GMR resistors under the flux concentrator do not. This imbalance
leads to the bridge output.
5K GMR Resistors
(Reference Elements)
5K GMR Resistors
(Sensing Elements)
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Flux Concentrators
Introduction