AA and AB-Series Analog Sensors

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AA and AB-Series Analog Sensors

NVE’s AA and AB-Series analog GMR sensors offer unique and unparalleled magnetic sensing

capabilities. These sensors are characterized by high sensitivity to applied magnetic fields, excellent

temperature stability, low power consumption, and small size. These characteristics make them

suitable for use in a wide variety of applications from rugged industrial and automotive position,

speed, and current sensors, to low-voltage, battery-powered sensors for use in hand-held

instrumentation and implantable medical devices. The unmatched versatility of these basic magnetic

sensors makes them an excellent choice for a wide range of analog sensing applications.

The AA-Series sensors use NVE’s patented GMR materials and on-chip flux concentrators to provide

a directionally sensitive output signal. These sensors are sensitive in one direction in the plane of the

IC, with a cosine-scaled falloff in sensitivity as the sensor is rotated away from the sensitive direction.

Also, these devices provide the same output for magnetic fields in the positive or negative direction

along the axis of sensitivity (omnipolar output). All sensors are designed in a Wheatstone bridge

configuration to provide temperature compensation. Two packages are offered, an SOIC8 and an

MSOP8. These sensors are also available in die form on a special-order basis.

There are three families of NVE’s basic AA-Series sensors: the standard AA-Series, the AAH-Series,

and the AAL-Series. Each of these sensor families uses a different GMR material, with its own

characteristics. The comparison table below summarizes the different characteristics of the GMR

materials:

Parameter

AA Series

AAH Series

AAL Series

Sensitivity to Applied Fields

High

Very High

High

Field Range of Operation

High

Low

Medium

Hysteresis

Medium

High

Low

Temperature Range

High

Very High

Very High

The AB-Series sensors are differential sensor devices, or gradiometers, which take advantage of the

high output characteristics of NVE’s GMR materials. Two families of AB sensors are offered, the

standard AB-Series and the ABH-Series. They have operational characteristics similar to the AA and

AAH sensors described in the table above but with the bipolar linear output characteristics of a

differential sensor.

Within these different sensor families, customers can find an excellent match to their analog sensor

requirements.