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TLE5014
GMR-Based Angle Sensor
Examples
SENT with error code 4091 in data range
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 12 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, 1 LSB corresponds to 360°/4088 = 0.0881°.
A read-out of "1" corresponds to an angle of 0°, an read-out of "4088" equals an angle of 359.9119°
The angle is calculated as follows:
Angle ° [ ]
9.2
Angle Base Calculation
The angle base is a 14-bit value which is stored in EEPROM address 0x00A0. This value defines the "zero-angle"
and all output values are in reference to this value. The angle base is stored in bit [15:2], bit [1] is used to define
the rotation direction of the output angle. Bit[0] of this register is not used.
To determine the zero-angle, the application is positioned to the desired angle and the angle value is read.
This can be done either by reading the angle via the 12-bit protocol (SENT / SPC / PWM) or by directly reading
the angle value register 0x02 via SICI and obtaining a 15-bit angle value. To avoid any quantization error, the
direct read of the 15-bit the angle value is the preferred method.
For programming the 16-bit EEPROM register 0x00A4, the 14-bit angle base together with the 1-bit rotation
direction information has to be combined to a 16-bit word which then can be written to EEPROM address
0x00A4. The 14-bit angle base must be in bit [15:2], the rotation information in bit [1], bit [0] is unused and has
to be "0". This procedure for construction the 16-bit word is described in the following.
First, the angle value has to be scaled to 14 bit (multiplied by 4 in case the 12-bit value is used) and shifted two
bits to the left (multiplied by 4).
This value has bit [1] set to "0" (counter-clockwise, ccw). In case the rotation direction should be set clockwise
(cw), bit [1] has to be modified and set to "1". This is performed by adding "2" to the calculated value.
Example:
12-bit angle value is 512 LSB (= 45°) This should be the new angle base.
Table 16
Example for Angle Base Calculation
Value decimal
Value HEX
512
0x0200
2048
0x0800
8192
0x2000
8192
0x2000
User's Manual
360°
Angle ° [ ]
----------- - readout LSB 12 ]
=
4096
360°
----------- -
⋅
=
4088
Description
12-bit angle value from sensor, should be new angle base
Angle value is scaled to 14 bit (multiplied by 4)
Angle value is shifted two bits to the left (multiplied by 4)
Value to be burned to EEPROM address 0x00A4 in case rotation direction
is ccw
⋅
[
r ( eadout LSB' 12 ] 1 )
[
45
–
Rev. 1.0
2019-03-12
(9.5)
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