Triaxis®: Unique position sensing solution
Triaxis® is an innovative magnetic sensor technology capable of very precise 3 axis magnetic field measurement from a single sensor. Endless linear, angular and 3D applications for example for powertrain (conventional, hybrid and electric), body, comfort and lighting, chassis and safety can be developed.
Traditional Hall sensors are only sensitive to the magnetic flux density perpendicular to the surface of the Hall element and consequently IC and package. These single-axis devices enable many applications like accelerator pedal position detection, joystick position detection, and proximity sensing, among others. Due to their 1D nature, and the fact that the output is proportional to the magnetic flux density, it is sometimes necessary to design complicated magnetic structures to achieve the desired measurement range and accuracy, especially over a wide temperature range due to the thermal drift of the measured magnet.
Triaxis® sensors, on the other hand, are an innovative magnetic sensor technology that enables measurement of the three magnetic flux components in a single integrated circuit. This is done by combining standard planar Hall effect technology with a unique Integrated Magnetic Concentrator (IMC®). Using the three magnetic components, it is possible to create 2D or 3D sensors that determine rotary (angle), linear (stroke), or even joystick type motion or 3D-magnetometers that output the individual magnetic (X, Y, and Z) components.
Strengths of Triaxis®
Triaxis® sensors are small, capable of high temperature operation and can support a wide variety of sensing applications by adjusting the on-chip magnetic angle computation. A single IC can support anywhere from one to three types of applications just by reprogramming the device. Since the angular computation is a relative measurement between two or three magnetic flux components the measurement is robust to temperature variations but also magnetic and mechanical (for example airgap, eccentricity) tolerances. Additionally, if an additional calibration process is performed after assembly, excellent linearity and accuracy can be obtained as mechanical tolerances are compensated for and a variety of simple, low cost magnets can also be used.
As a magnetic field is being sensed in a non-contacting manner the sensors are intrinsically insensitive to dirt, dust, oil, gas and other contaminants. The IC itself can be overmolded in plastic or potted to protect the IC from these contaminants and ensure long life even when exposed to harsh media.
Triaxis® is an unique and innovative magnetic sensor technology capable of very precise 3 axis magnetic field measurement from a single sensor.
A variety of IC packages are available from the industry standard SOIC-8, TSSOP-16, and QFN-16 to the Melexis Dual-Mold Package (DMP-4). The SOIC-8, QFN-16, and DMP-4 all contain a single sensor die. The TSSOP-16 contains two sensor dies that are fully redundant with independent supply, ground, and output enabling redundant operation for systems requiring a higher level of safety or availability. The DMP-4 is intended to be integrated without a PCB via a direct connection to the connector leadframe. This can bring packaging, cost, and reliability advantages.
Finally, Triaxis® sensors are ASIL-ready and contain a suite of onboard diagnostics to ensure safe and correct operation. Melexis can provide additional supporting documentation to conduct the necessary safety analysis to ensure ASIL/ISO26262 requirements are met.
Where are Triaxis® sensors used?
Triaxis® sensors are used for automotive position sensing in different applications like steering angle, pedal position, electronic throttle body, EGR valve, shifter, turbo actuator, motor position, chassis height, and more. There are also other fields where Triaxis® sensors could be used, beyond automotive. To name a few applications: Agricultural vehicles and equipment, joysticks, man-machine interfaces, heavy-duty vehicles, forklifts, robots, wheelchairs, industrial cranes, and more.
Triaxis® features and benefits
- First 3D magnetic sensor
- Position (via on-chip computation) or vector output
- Variety of output protocols: Ratiometric analog, PWM, SENT, SPI, I2C
- Enhanced self-diagnostics features for fail-safe operation
- 5V and 3.3V supply voltage
- High thermal stability (up to 160 °C)
- Immune to interference due to dust, dirt, and liquids
- Tolerant to assembly variances thanks to the programmable nature
- Simple, low cost magnet requirements
- Dual mold package enabling integration without a PCB
- Industry standard SOIC-8, TSSOP-16, and QFN-16 packages available