TF952 TMR sensor for magnetic fields
General information
The TF952 magnetic field sensor based on the Tunnel MagnetoResistive (TMR) effect.
The sensor offers
- Extremely low harmonic output signals
- Non-contacting measurement
- A large working distance
- High signal amplitudes with simultaneously low offset voltages
- High stability across the temperature application range
Application examples
Suitable for absolute or incremental applications (linear or rotary motion) e.g.:
- Switching applications
- 2D-magnetic field measurements
Product overview
| Name | Housing | Sensitivity | Offset | Bridge resistor |
|---|---|---|---|---|
| TF952 | FlipChip | 9 mV/V/mT | ±3 mV/V | 100 kΩ |
General information
The TF952 is a magnetic field sensor based on the Tunnel MagnetoResistive (TMR) effect. The Sensor contains two Wheatstone bridges. This allows the measurement of two magnetic field directions (X and Y) in parallel.
The sensor is ideal for measuring magnetic fields in a linear range from -20 mT up to 20 mT. A typical application is endpoint detection of pneumatic or hydraulic cylinders.
The sensor is a flipchip sensor and suitable for SMD assembly on a PCB.
The sensor is currently under development.
Please ask us for further information or samples.
Further application possibilities
TF952 as flat position sensor.
The TF952 can be used not only as a field sensor but also as a normal flat position sensor. For this purpose, the sensors are arranged and wired directly to the scale in a specific combination.
With a 2 mm pole pitch, the sensors show a very good signal performance at a working distance of about 1.4 mm, so that the measurement errors can be reduced to less than ±30 µm.
Design features
Sensitec is increasing the sensor efficiency by means of various design modifications to the chip layout. The patented solutions, described more closely below, also contribute to better signal quality, reduced sensitivity to stray fields and increased control accuracy.
FreePitch
FreePitch sensors have been optimized to the extent that they can be used independent of the pole length of the measurement scale. This has the benefit of them being particularly compact and coming very close to a point sensor. They are the ideal choice if a particularly cost-effective solution is needed for the measurement task. In order to keep the dimensions as small as possible, the Wheatstone bridges are nested within each other. In order to generate the sine/cosine signals, both bridges are positioned at an angle of 45° to each other.
FreePitch sensors can be used with pole rings or linear scales with almost any pole length, as well as with dipole magnets.
PerfectWave
The PerfectWave design is applied in order to optimize the signal quality of the FreePitch sensors. The MR strips that serve as resistors have a curved form which is used to filter the harmonics when mapping the magnetic field direction in an electric signal. This filtering is implemented using the special geometry and arrangement of the MR strips and does not cause any additional signal propagation delay. The PerfectWave design is particularly effective for small magnetic fields and results in improved linearity, higher accuracy and better signal quality.