Infineon TLE4961-3L Hall-Effect Latch: Datasheet, Application Circuit, and Replacement Guide
The Infineon TLE4961-3L is a high-precision, high-reliability Hall-effect latch designed for demanding automotive and industrial applications. This sensor provides magnetic switching with outstanding temperature stability, making it an ideal choice for position and speed sensing in harsh environments, such as in camshaft and crankshaft detection, window lifters, and seat positioning systems.
Datasheet Overview and Key Features
The TLE4961-3L operates from a supply voltage range of 3.0 V to 32 V, ensuring compatibility with both 3.3V/5V logic systems and robust 12V/24V automotive supplies. Its key performance characteristics include:
Reverse Polarity Protection (-18V), safeguarding the sensor from accidental miswiring.
A wide operating junction temperature range of -40 °C to 170 °C.
Low Power Consumption, typically 3.5 mA, which is critical for battery-operated systems.
Short-Circuit and Overload Protection on the output pin.
Precise Magnetic Thresholds (Bop and Brp) with tight tolerances, ensuring consistent and reliable switching points.
The device features an open-drain output that can sink up to 25 mA, allowing it to directly interface with microcontrollers or other logic circuits.
Typical Application Circuit
Integrating the TLE4961-3L into a design is straightforward. A standard application circuit requires only a few external components for stable operation:
1. Power Supply Decoupling: A 100 nF ceramic capacitor (C1) placed as close as possible to the VS pin of the sensor is essential to suppress high-frequency noise on the supply line.
2. Pull-up Resistor: The open-drain output requires an external pull-up resistor (Rpull-up) to the logic supply voltage (e.g., 3.3V or 5V). A value between 1 kΩ and 10 kΩ is typical, balancing current consumption and switching speed.
3. Load Dump Protection: For automotive environments, additional external protection components like a Transient Voltage Suppression (TVS) diode may be necessary on the supply line to handle load dump events, although the IC has robust internal protection.
The magnetic field from a permanent magnet is applied perpendicularly to the branded side of the package. The output switches low when the south pole exceeds the operating threshold (Bop) and switches high when the north pole exceeds the release threshold (Brp).
Replacement and Cross-Reference Guide
When replacing the TLE4961-3L or selecting an alternative, it is critical to verify several parameters to ensure drop-in compatibility and system reliability.
Package Compatibility: The TLE4961-3L is offered in a standard SOT-23 (PG-SC59) 3-pin package. Ensure the replacement part has the same pinout (1. VS, 2. GND, 3. Output).
Logic Output Type: Confirm the replacement is also a latch (not a switch or bipolar lock) with an open-drain output.
Electrical Characteristics: Match the supply voltage range, output current capability, and especially the magnetic switching points (Bop/Brp).
Suggested Equivalents/Alternatives: While direct second-source equivalents are rare for such a specialized part, designers often compare it to other automotive-grade Hall latches from manufacturers like Allegro Microsystems (e.g., A1220 series) or Diodes Incorporated. However, a thorough review of the respective datasheets is mandatory, as subtle differences in magnetic behavior or protection features can significantly impact performance in the application.
ICGOOODFIND
The Infineon TLE4961-3L stands out as a premier solution for high-temperature, high-reliability position sensing. Its robust integrated protection features, precise magnetic characteristics, and automotive-grade qualification make it a top-tier choice for designers. When considering a replacement, a meticulous parameter-by-parameter comparison is the ICGOODFIND to guaranteeing system integrity and avoiding costly redesigns.
Keywords: Hall-Effect Latch, Automotive Sensor, Magnetic Switching, Reverse Polarity Protection, SOT-23 Package.
