Hall-effect sensors for cars, industry, white goods

August 11, 2016 // By Christoph Hammerschmidt
Infineon has developed a family of Hall-effect sensors that excel through high integration and low power consumption. The TLx496x family is available in three variants – for automotive electronics, for industrial applications and for consumer electronics.

The new sensors consume no more than 1.6 mA, about 50 % less than comparable products, claims Infineon. The 5V – which are designed for automotive applications – content themselves with even less - 1.4 mA. According to the vendor, all models of the TLx496x series feature high ESD robustness and precise, stable magnetic switching points which makes them suitable for for systems where energy efficiency, robustness and precision matter. Due to their high integration, the devices make two to four of the previously needed passive components redundant; the TLx496x Hall sensors therefore help reducing system costs as well as the PCB space needed.

All of the TLx496x Hall sensors integrate the Hall element, a voltage regulator, choppers, an oscillator and an output driver. The voltage regulator powers the Hall element and the active circuits. The chopper ensures that the temperature remains stable and minimizes the effects of process fluctuations, which occur for three reasons: First, each single Hall sensor has a slightly different magnetic switching point as a result of the manufacturing process; second, the permanent magnets in the brushless DC (BLDC) motor lose magnetic field strength as the temperature rises and third, the Hall output voltage is affected by stress and temperature. The TLx496x Hall sensors compensate all of these effects.

The variants with an “E” in the type designation (TLE496x-xM) are suitable for automotive applications with an operating voltage of 3.0 V to 5.5 V, which generally are not exposed to overcurrent. Target applications include power windows and sunroofs, trunk locks, windshield wipers, seatbelts, camshafts, shift levers and the many controls used in BLDC motors and, more general, all systems that need a precise Hall-effect sensor for an expanded temperature range of -40 °C to 170 °C.