What this Hall switch does and where it fits
The TLV4946K is a unipolar Hall-effect switch from Infineon, designed for position and proximity sensing in environments that see wide temperature swings — the operating range spans -40°C to 150°C. It switches on when a south-pole magnetic field exceeds 13.9 mT and releases at 5 mT, with an open-collector output that sinks up to 20 mA. Supply voltage down to 2.7 V lets it run directly off a 3.3 V rail without a separate LDO, saving a component on the BOM.
Magnetic thresholds and temperature compensation
The 13.9 mT operate point and 5 mT release give a 8.9 mT hysteresis — wide enough to reject mechanical vibration and magnetic noise in a motor-drive or valve-position application. Temperature compensation is listed as a feature, meaning the switch point stays stable across the -40°C to 150°C range rather than drifting with the magnet's own temperature coefficient.
Sourcing and lifecycle status
the surface-mount footprint suits standard reflow assembly.