Hi Koldo,
First of all, the LOS, DOS and DOS over-range fault detection mechanisms are based off the monitor signal. The monitor signal is a combination of both the sine and cosine signals. Please see its formula in Page 16 of the datasheet . If the resolver is at 0 degrees, the monitor signal maximum amplitude is dominated by the cosine signal and is therefore the maximum differential peak to peak amplitude of the cosine signal. If the resolver is at 90 degrees, the monitor signal is dominated by the sine signal and is therefore the maximum differential peak-to-peak amplitude of the sine signal. At angles in between the monitor is a combination of the two signals but for sine and cosine signals that have equal maximum amplitudes the monitor signal will have a constant maximum amplitude.
The monitor signal is checked at intervals defined by the window counter period (Check Table 5 in page 17 of the datasheet). This means you always get a peak of the incoming signals.
To answer the questions,
- The LOS threshold for sin/cos signals is defined by the user. This is being compared to the max amplitude of the monitor signal being applied to the device.
- The max amplitude of the monitor signal is being compared with a set threshold for DOS overrange threshold.
- For the DOS mismatch threshold, the maximum value of the monitor signal is checked at the end of each window counter period. The maximum value and minimum value are stored and compared and if the difference exceeds the threshold this triggers a fault.
- You based this question to Item 3, but the answer could fall under "Other" so I think it is irrelevant to answer this.
- This error represents the difference between the angular error of the rotor and the digital angle output of the converter.
Regards,
Johnny