DMU380ZA Series
User’s Manual
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Doc# 7430-3810 Rev. 02
Page 42
limits that control the sensor over-range bit in the diagnostic status register (Table 23); if
the system undergoes motion that exceeds this limit, the over-range bit is set. The default
scaling is 125.0°/sec; to change the scaling to 62.5°/sec, the master sends 0xB901.
The rate sensor dynamic range selection maps to a bit-weight scale factor as defined in
Table 28.
Table 28 Rate-Sensor Scaling Factor
Dynamic Range
Scale Factor
+/-62.5°/sec
400 LSB/( °/sec )
+/-125.0°/sec
200 LSB/( °/sec )
+/-250.0°/sec
100 LSB/( °/sec )
The digital low-pass filter register sets the type and cutoff frequency of the filter applied
to the scaled sensor data. The default setting is a 5 Hz Bartlett filter; to switch to a 20 Hz
Butterworth filter, the master sends 0xB840. Figure 14 describes the output response of
the different Bartlett filter settings.
Figure 14 DMU380ZA Bartlett Filter Response
5.7.4
Magnetic-Alignment
On models with magnetometers and AHRS or INS algorithms (INS380ZA and
AHRS380ZA), the system is capable of compensating for the hard-iron bias and soft-iron
scaling of the mounting environment. Once found, the values are used by the Kalman
filter algorithm to compensate the heading for the magnetic environment. A complete
