TLE5011 datasheet(8/45 Pages) INFINEON

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TLE5011

Functional Description

Final Data Sheet

V2.0, 2011-03

Functional Description

2.1

General

The GMR angle sensor is implemented in vertical integration. This means that the GMR active areas are

integrated above the logic portion of the TLE5011 device. GMR elements change their resistance depending on

the direction of the magnetic field.

Four individual GMR elements are connected to one Wheatstone sensor bridge. These GMR elements sense

either of two components of the applied magnetic field:

•

X component, V

X (cosine)

•

Y component, V

Y (sine)

The advantage of a full-bridge structure is that the amplitude of the GMR signal is doubled.

Figure 1

Sensitive Bridges of the GMR Angle Sensor

Note: In Figure 1, the arrows in the resistor symbols denote the direction of the reference layer, which is used for

the further explanation (Figure 2).

The output signal of each bridge is only unambiguous over 180° between two maxima. Therefore two bridges are

orientated orthogonally to each other to measure the 360° angle range.

Using the ARCTAN function, the true 360° angle value can be calculated that is represented by the relation of the

cosine (here X) and sine (here Y) signals.

Because only the relative values influence the result, the absolute size of the two signals is of minor importance.

Therefore, most influences on the amplitudes are compensated.

VDDG

GND

ADCX+

GMR Resistors

ADCX-ADCY+ADCY-

0°

90°

TLE5011 Datasheet(PDF) 8 Page - Infineon Technologies AG