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TLE5014
GMR-Based Angle Sensor
Examples
Table 16
Example for Angle Base Calculation (cont'd)
Value decimal
Value HEX
8194
0x2002
8194
0x2002
In case the sensor is configured to SENT interface with the option of "4091" as error code in the data range, the
calculation has to be modified as in this case not the complete 12 bit are available for sensor output. The angle
values have to be scaled differently to 16 bit in this case. The data range in this case is 1... 4088 LSB. The
notation used for this case is [LSB'12] in contrast to [LSB12], which means the full 12-bit resolution (0... 4095)
In this case, the calculation of the angle base is different:
Determine the angle value according to
Round this value and shift it by 2 bits (multiply by 4).
Example:
Angle value is 436 LSB. This should be the new angle base.
Table 17
Example for Angle Base Calculation with "4091" Error Code enabled
Value decimal
Value HEX
436
0x01B4
38.307°
--
1743
0x06CF
6972
0x1B3C
6972
0x1B3C
6974
0x1B3E
6974
0x1B3E
So the total formula for constructing the 16-bit word containing angle base and rotation direction (rotation
direction ccw) is in this case:
[
Anglebase LSB 16
For changing the rotation direction to clockwise (cw), add 2 to Anglebase[LSB16].
9.3
Look-up Table Calculation
The look-up table consists of 32 values, each 16 bit, which are stored in the sensor EEPROM and used for
output linearization. In this way, non-linearities which come for example from external magnetic circuit
assembly tolerances, can be compensated. The 32 values for the look-up table have to be generated with an
external reference encoder which allows to precisely position the sensor to defined angular positions. At this
defined position, the sensor output signal is read and the correction value for the look-up table is calculated.
This value has to be stored at the corresponding address (see
User's Manual
Description
Add 2 for setting bit [1] (rotation direction clockwise)
Value to be burned to EEPROM address 0x00A4 in case rotation direction
is cw
Equation (9.5)
and scale it to 14 bit by multiplying with 2^14/360.
Description
Angle value from sensor, should be new angle base
Angle value in [°] according to
Angle value is scaled to 14 bit and rounded (multiplied by 2^14/360 and
rounded)
Value is shifted by two bits to the left (multiplied by 4)
Value to be burned to 0x00A4 in case rotation direction is ccw
Add 2 for setting bit [1] (rotation direction clockwise)
Value to be burned to 0x00A4 in case rotation direction is cw
æ
2
----------- -
]
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=
4 round
4088
è
46
Equation (9.5)
14
⋅
r ( eadout LSB' 12 ] 1 )
[
Table
10).
(9.6)
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Rev. 1.0
2019-03-12
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