The TMR angle sensor is suitable for automotive applications and its application in various fields is expected to increase in the future.

e4ds webinar was held on August 18th with the theme of ‘Infineon’s Automotive Magnetic Angle Sensor Solution, an Essential Technology for Future Automobiles’.

This webinar was presented by Hyunjung Kim, Manager at Infineon.

Magnetic sensors can be considered if there is an application that requires non-contact detection of the movement of an object, and are used in numerous applications such as rotor position sensors for motors, pedal position sensors for automobiles, joysticks, and joint movements for robots.

According to the webinar, many MR sensors such as GMR, TMR, and AMR are currently in use, and sensor selection is required based on angle accuracy, resolution, temperature, etc., and various requirements are required before development, such as △sensor selection △air gap setting △optimized magnet design.

In the case of the dual TMR (Tunnel Magneto Resistance) sensor, it shows a large resistance change when the same magnetic field is applied compared to the GMR sensor, so it has higher sensitivity.

Manager Kim Hyun-jung said that when designing a magnetic circuit, the most important points are: △How can the magnetic circuit structure be made as simple as possible?It is important to consider factors such as whether the sensor can be configured as is, whether there is a stray field around it, and to select a sensor by understanding the precision and accuracy specifications of the intended application.

In addition, calibration was a big issue for developers when selecting a sensor, and Infineon also recommends calibration, but it is said that there is an advantage in that the calibration algorithm can be checked through the application note and calibration can be performed through the provided GUI without having to calculate it directly.

A representative product is Infineon's TLE5501, a TMR sensor with an output voltage of up to 370㎷/V. It can be connected to μC without an internal amplifier due to its high output voltage, showing high sensitivity, and its extremely low temperature drift reduces additional processes for calibration and temperature compensation. In particular, it shows low power consumption of up to 2mA.

In addition, as a single-die product that satisfies ASIL-D at a low price, its use in automotive applications is expected to increase in the future.

It is widely used in representative applications such as △pedal △actuator △throttle △sash △EPS motor position △SAS rotary switch, etc.