CMA3000-D0X VTI Hamlin, CMA3000-D0X Datasheet - Page 28

• Manufacturer Part Number: CMA3000-D0X
• Description: Cma3000-d0x Series 3-axis Accelerometer
• Manufacturer: VTI Hamlin

8.4 Noise
VTI Technologies Oy
www.vti.fi
Linearity error is the deviation from the best bit straight line. See Figure 21.
Linearity error is calculated by
Equation 6
where LinEr
is sensor’s measured Z-axis output [counts] on input acceleration acc, Output
nominal output [counts] on input acceleration acc, Sens is sensor’s nominal sensitivity [counts/g] and
FS is sensor’s full scale measuring range [g] (for example for CMA3000-D01 with ±2g setting →
FS = 2 g).
Sensor’s ideal output Output
accelerations from –FS to FS.
Output noise n
values when the sensor is in 0 g position at room temperature. Average noise/axis is calculated by
LinEr
Figure 20. Centrifugal acceleration applied for CMA3000 Z-axis.
CMA3000 output
readings
Figure 21. CMA3000’s linearity error at input acceleration acc.
Z
Z
-FS
−
axis
@
Z-axis@acc
acc
Sensor’s ideal
output
X
, n
=
X
Y
Y
Output
is sensor’s Z-axis linearity error [%FS] on input acceleration acc, Output
and n
Doc.Nr. 8281000.12
Z
Pin #1
Z
in X,Y and Z directions is the measured standard deviation of the output
−
axis
@acc
Sens
Acceleration reading
from CMA3000 [g]
@
acc
(in Equation 6) is calculated by fitting a straight line to measured
⋅
−
FS
Output
acc
Centrifugal
acceleration
for Z-axis
@
acc
+FS
Possible offset error is not
included into linearity error
⋅
100
CMA3000 linearity
error in [g] at input
acceleration acc
%
Input acceleration [g] (centrifugal
acceleration in parallel to
CMA3000 measuring axis)
,
CMA3000-D0X Series
@acc
is sensor’s
Z-axis@acc
Rev. 0.12
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