Hall latch for commutation and position sensing
The TLI4946-2L is a South Pole-polarised Hall-effect latch from Infineon, designed for brushless DC motor commutation, speed sensing, and rotary position detection. It switches its open-drain output when the magnetic field crosses the 3.5 mT trip threshold and releases at -3.5 mT, giving 7 mT of hysteresis that rejects vibration and stray fields. Temperature compensation stabilises the magnetic switch point across the full -40°C to 125°C ambient range, so the sensor doesn't drift with self-heating in a motor housing or under-hood environment. Supply voltage is 2.7 V minimum, and the open-drain output sinks up to 20 mA continuous — enough to drive a PLC input or a small relay coil through a pull-up resistor.