TLE4955C Datasheet, PDF (3/21 Pages) Infineon Technologies AG – Differential Hall Effect Transmission Speed Sensors

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TLE4955C
Functional Description
1
Functional Description
The differential Hall sensor IC detects the motion of tooth and magnet encoder applications. To detect the
motion of ferromagnetic objects, the magnetic field must be provided by a back biasing permanent magnet.
Either south or north pole of the magnet can be attached to the rear unmarked side of the IC package.
The magnetic measurement is based on three equally spaced Hall elements, integrated on the IC.
Both magnetic and mechanical offsets are cancelled by a self calibration algorithm.
The sensor includes a current output PWM protocol.
1.1
Sensor Assembly
The output signals for a south biased sensor with a magnetic encoder and ferromagnetic tooth wheel will be
issued in the following way.
The tooth wheel is rotating in clockwise above the sensor. The output pulse will be issued by reaching the
hysteresis levels after the pre low time. For a tooth wheel with ideal pitch (tooth to tooth) of 5 mm the
direction signal achieves a phase shift of 90° compared to the speed signal.
Sensor and back bias magnet can be applied in the following ways:
N
S
S
N
S
N
N
S
CCW
S
N
CW
CCW
CW
CCW
CW
GYSY00W 001155W
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GY_SSY₀₀W₁₅W
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VDD GND
N
N
S
S
VDD GND
Figure 1 Sensor Assembly and Definition of Rotating Directions
GY_SSY₀₀W₁₅W
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S
S
N
N
VDD GND
Data Sheet
3
Version 1.0
2016-06-15