AG920-07 NVE, AG920-07 Datasheet - Page 96

• 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

GMR Magnetic Gradient Sensors (Gradiometers)
The NVE gradiometer is a GMR magnetic field sensor used to detect field gradients between
Wheatstone bridge configured resistors. This device is “unshielded” (i.e., it does not employ resistor
shields) therefore all four (4) legs of the Wheatstone bridge are active (they respond to changes in field
level). Gradiometers can be used to detect either magnetic or ferrous targets. To detect gradient
changes caused by the proximity to a moving ferrous target, a biasing magnet is required. Refer to the
Magnetic Biasing section and the GT Sensor application notes for gradiometer biasing guidelines.
The output of the gradiometer differs from that of a standard GMR Magnetic Field Sensor. The
gradiometer’s output can be bipolar versus unipolar and can be shaped by the use of magnetic biasing
and the application of external flux shaping devices (flux guides). The figure below shows an example
design:
Silicon substrate
(1250 µm x 650 µm)
Bonding pads (4)
(100µm x 100µm)
B
ASIC
www.nve.com
G
RADIOMETER
Axis of sensitivity
A ctive resistor pairs
phone: [phone] fax: [phone]
- 96 -
B
RIDGE
Unused resistor pairs
(different resistor spacing may be
incorporated based on application)
S
ENSOR
Application Notes
Metal interconnects
L
AYOUT