Vertical dual-Hall sensor for rotation direction and speed detection

December 20, 2013 // By Graham Prophet
TLE4966V is a vertical dual-Hall sensor for detecting rotation direction and speed. The TLE4966V is the first dual-Hall device with its integrated Hall plates oriented vertically and not horizontally on the chip surface, thus making it sensitive to magnetic fields with in-plane direction. This 90-degree orientation change provides flexibility to fit designs into space-constrained areas.

The design flexibility and the 4mA to 7mA current consumption of the TLE4966V suit it to energy-sensitive electronic automotive systems such as trunk lifts, power window lifts, sun roofs and seat adjustment. In non-automotive applications, the sensor is also an excellent solution for escalators, motorized window blinds and shades.

The TLE4966 switch family is designed to detect the rotation direction and rotation speed of a magnetic pole wheel. The vertically integrated Hall plates in TLE4966V enable sensing of in-plane, instead of perpendicular, magnetic fields. Changing sensing orientation by 90 degrees allows system engineers to design new mechanical concepts. This is especially valuable for space-restricted applications such as power window lifts and electronic trunk lifts.

Detecting the direction and speed of rotation of a magnetic pole wheel requires two separate Hall plates. Due to the distance between the two plates, they detect slightly different signals at any designated time, generating a phase difference. During a rotation direction change, the phase difference changes polarity. The TLE4966V detects this change and delivers a corresponding signal. The rotation speed of a magnetic pole wheel can directly be calculated with the second sensor output signal. This signal is triggered by each polarity change of the magnetic field.

The two integrated vertical Hall plates on one silicon die within the TLE4966V have the same behaviour for temperature and lifetime stress, with no sensitivity deviation over lifetime. The TLE4966V has two signal outputs: one signal for the magnet rotation direction, the other signal for the pole wheel rotation speed. That means that a single device delivers all relevant information where previously two sensors have been required.

The TLE4966V performs on-chip signal processing, with rapid sensor signal availability for fast applications and no microcontroller programming. The TLE4966V sensor allows operation from an unregulated power supply, compatible with systems from 3.5V to 32V. It comes in a Thin Small Outline Package with 6 pins (TSOP-6).

Infineon; /