TMR40XX High Sensitivity Analog Gear Sensors

The TMR40XX analog geartooth sensors are highly sensitive to magnetic gradients and optimal for small pitch gear measurements. They are also tolerant to wide air gaps and external magnetic fields. 

Click here to view TMR40XX datasheet.

Features:

• Tunneling magnetoresistance (TMR) technology;
• High saturation field allows operation in large DC magnetic field;
• High sensitivity to magnetic gradient;
• Compatible to small pitch gear measurement;
• Sine/cosine signal output with accurate phase difference;
• Excellent resistance to external magnetic field interference.

Applications:

• Gear speed and direction sensing;
• Linear and angular speed sensing;
• Linear displacement sensing;
• Angular displacement sensing;
• Magnetic scale;
• Magnetic encoder

General Description:

The TMR40xx series of geartooth sensor adopts a unique push-pull Wheatstone bridge design. This design includes a single-channel or dual-channel Wheatstone full bridge composed of four or eight unshielded high-sensitivity tunneling magnetoresistance (TMR) sensing elements. The Wheatstone bridge provides a differential voltage output along the gradient of the applied magnetic field along the sensor's sensing direction.

The dual-channel Wheatstone full bridge generates two orthogonal sine/cosine voltage output signals to measure the position of the gear rotation and detect the direction of rotation. The high-sensitivity performance of the TMR40xx series enables detection of small magnetic field changes, and its output signal has good temperature stability.

TMR40xx series provides multiple configuration of TMR sensing element spacing: 0.25mm, 0.4mm, 0.5mm, 0.6mm, 0.75mm, 0.8mm,1.0mm,1.2mm,1.4mm, 1.6mm, 2.0mm, and 3.0mm. It is available in two compact LGA packages with dimensions of 3mm×3mm×0.9mm and 3mm×6mm×0.9mm.