Generalities
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.
Three families of NVE's basic AA series sensors are offered : 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.
| AA | AAH | AAL | |
| 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.
Kits and documentations
AG001-01 - Analogous sensors
The kit contains several references among the AA and AB series and a choice of magnets of polarization and PCB. It also contains application notes CDROM and a catalogue.