CMA3000-A0X VTI Hamlin, CMA3000-A0X Datasheet - Page 11

• Manufacturer Part Number: CMA3000-A0X
• Description: Cma3000-a0x Series 3-axis Accelerometer
• Manufacturer: VTI Hamlin

5.2.1
5.2.2
5.3 Linearity
VTI Technologies Oy
www.vti.fi
Sensitivity calibration error
Sensitivity temperature error
Pin #1
Sensitivity is calculated by
Equation 3
where Sens
reading [counts] in +1 g position and Output
position.
Sensitivity calibration error is the difference between sensor’s measured sensitivity and the nominal
sensitivity at room temperature conditions. Error is calculated by
Equation 4
where Sens
sensitivity [counts/g] at room temperature conditions and Sens is sensor’s nominal sensitivity
[counts/g].
Sensitivity temperature error is the difference between sensor’s sensitivity at different temperatures
and the calibrated sensitivity. Error is calculated by
Equation 5
where Sens
axis@T
measured Y-axis sensitivity [counts/g] at room temperature RT.
The needed accurate input acceleration in linearity characterization is generated using centrifugal
force in centrifuge, see Figure 10. The RPM of the centrifuge is sweeped so that wanted input
acceleration values are applied in parallel to the sensor’s measuring axis.
Sens
Sens
Sens
Figure 9. CMA3000 positions for Y-axis sensitivity measurement.
is sensor’s measured Y-axis sensitivity [counts/g] at temperature T and Sens
Y
Y
Y
−
−
−
axis
axisCalibE
axisTempEr
=
Y-axisTempEr@T
Y-axisCalibEr
Y-axis
Output
r
@
is sensor’s Y-axis sensitivity in [counts/g], Output
=
T
PRELIMINARY - Subject to changes
Y-axis in +1 g
position
X
Sens
=
is sensor’s Y-axis sensitivity calibration error in [%], Sens
Y
Sens
−
is sensor’s Y-axis sensitivity temperature error in [%] in temperature T, Sens
axis
Y
−
Doc.Nr. 8282100.05
Sens
axis
@
Y
+
−
Z
1
axis
g
−
Sens
2
−
Sens
@
g
Output
T
Y
−
−
axis
Sens
⋅
100
@
Y
RT
−
%
Y
axis
−
Y-axis@-1g
axis
,
Pin #1
@
Z
@
−
1
RT
g
,
Y-axis in -1 g
position
⋅
is sensor’s Y-axis output reading [counts] in -1 g
100
%
,
X
Y-axis@+1g
Earth’s
gravitation
sensor’s Y-axis output
Y-axis
CMA3000-A0X Series
Y-axis@RT
sensor’s Y-axis
is sensor’s
Rev.05
11/ 17
Y-