Data Sheet

3

Version1.0

2016-06-15

TLE4955C

Confidential

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:

Figure 1

Sensor Assembly and Definition of Rotating Directions

CW

S 0015

4952

N

S

S

S

S

S

N

N

N

N

S 0015

4952

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VDD

GND

CCW

CW

CCW

CW

CCW

S 0015

4952

S 0015

4952

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GND

VDD

N

S

N

S

S 0015

4952

S 0015

4952

GND

VDD

N

S

N

S

GYYWW

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