Infineon TLE4968-1M Hall-Effect Latch: Features, Applications, and Design Considerations

The Infineon TLE4968-1M is a high-precision, Hall-effect latch designed for robust operation in demanding automotive and industrial environments. This magnetic sensor integrates a temperature-compensated Hall plate, advanced signal conditioning, and a short-circuit protected open-drain output into a single, miniature SOT23-3 package. Its core function is to provide a defined digital output switch in response to the magnitude and polarity of an applied magnetic flux, making it an essential component for position and speed sensing.

Key Features

The TLE4968-1M stands out due to its suite of high-performance characteristics. It operates from a wide supply voltage range of 2.7 V to 38 V, accommodating both low-voltage microcontroller interfaces and harsh automotive loads. A critical attribute is its reverse polarity protection up to -38 V, safeguarding the device from accidental miswiring. The sensor offers high magnetic sensitivity with precise, symmetrical switching thresholds (Bop and Brp), ensuring accurate and reliable switching points. Furthermore, it features low current consumption and is AEC-Q100 qualified, confirming its reliability for automotive applications. Its integrated protection circuits against overvoltage, undervoltage, and load-dump conditions contribute to its exceptional robustness.

Primary Applications

The combination of high reliability and precision makes the TLE4968-1M ideal for a vast array of applications. In the automotive sector, it is extensively used for sensing rotational speed in wheel speed sensing and transmission systems, as well as for detecting the position of camshafts, crankshafts, and gear teeth. Beyond automotive, it finds purpose in industrial systems for motor commutation in brushless DC (BLDC) motors, end-position detection in linear actuators, and as a reliable non-contact switch in white goods and consumer electronics where mechanical buttons are undesirable.

Critical Design Considerations

Successful implementation of the TLE4968-1M requires careful attention to several design factors. Magnetic circuit design is paramount; the strength and orientation of the magnet relative to the sensor must be calculated to ensure the magnetic flux density exceeds the specified switching thresholds. Designers must account for air gaps, temperature drift of the magnet, and mechanical tolerances. Electrical interfacing is another crucial area. While the open-drain output requires a pull-up resistor, its value must be chosen to balance switching speed and power dissipation. Proper PCB layout is essential to minimize noise interference; bypass capacitors should be placed as close as possible to the VSUP pin, and signal traces should be kept away from high-current paths. Finally, ensuring a stable and clean power supply is critical for avoiding erroneous switching events.

ICGOOODFIND

The Infineon TLE4968-1M is a highly robust and versatile Hall-effect latch that sets a high standard for magnetic sensing. Its exceptional reliability, wide operating voltage, and integrated protections make it a top-tier choice for designers tackling challenging automotive and industrial environments. Careful attention to magnetic and electrical design is key to unlocking its full performance potential.

Keywords:

Hall-effect latch

AEC-Q100 qualified

Reverse polarity protection

Magnetic circuit design

Non-contact switch