Analog Devices EVAL-ADA4570SDZ User Manual page 11

User Guide
EVALUATION BOARD SOFTWARE
Electrical Angle
The electrical angle plot displays the calculated arctan2 (angle)
value in a visual format, as shown in
Figure 21. Electrical Angle Plot
Sine and Cosine Plot
The sine and cosine plot, shown in
VCOS (differential signals) from the ADA4570. The radius calculat-
ed from VSIN and VCOS is indicated in the Radius indicator shown
in Figure 18.
Figure 22. Sine and Cosine Plot
Offset Calibration
An offset calibration may be required to maximize the accuracy of
the ADA4570. See the ADA4570
offset voltage ranges for the outputs.
The EVAL-ADA4570 GUI uses a maximum and a minimum output
value to calculate the VSIN channel and the VCOS channel offsets.
The GUI requires the user to perform at least one full electric angle
rotation to determine a meaningful offset value.
Click Apply Offset to enable the offset calibration. When the
calibration is applied, the light emitting diode (LED) turns bright
green (see Figure 23).
analog.com
Figure 21.
Figure 22, displays VSIN vs.
data sheet for full details on the
Figure 23. Offset Calibration Pane
Temperature Calibration
The EVAL-ADA4570SDZ GUI also allows the user to perform a
single point temperature calibration for the temperature channel
indicated in Figure 24.
Figure 24. Temperature Calibration Pane
Click the Cal. symbol to open a window to enter a reference tem-
perature. The GUI uses this temperature to calculate the offset and
applies it to the temperature measurement when the Cal Active
LED is enabled by the user (see
Figure 25. Temperature Calibration Activated
EVAL-ADA4570
Figure 25).
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