Preliminary
SCA1000 and SCA1020 Series
Accelerometer
FEATURES
• 2-axis measurement: SCA1000 for X - Y measurement and
SCA1020 for Z - Y measurement
• Available range
±1.7
g
• Interchangeable with SCA610/SCA620 (see interchangeability
drawing below)
• Over damped sensing element to control frequency response
• SMD DIL-12 lead-free component
• Compatible with lead-free reflow soldering process
• Advanced internal and external connection failure detection
• Digitally activated electrostatic self-test
• Continuous memory parity check
• Single +5 V supply; two ratiometric analog voltage outputs
• Serial Peripheral Interface (SPI) compatible digital output (11 bits)
• Internal temperature sensor, accessible via SPI
BENEFITS
• Excellent reliability and stability over time and
temperature
• High resolution and low noise
• Wide operating temperature range
• Outstanding overload and shock durability
APPLICATIONS
• 2-axis acceleration measurements
• 2-axis platform leveling
• Inclination based position measurement
• 360 ° vertical orientation measurement
For customized product, please contact VTI Technologies
ELECTRICAL CHARACTERISTICS
Parameter
Supply voltage Vdd
(1
Current consumption
Analog resistive output load
Analog capacitive output load
Digital output load
SPI clock frequency
AD conversion time
Data transfer time
@500 kHz clock
150
38
@ 500 kHz
Vdd = 5 V; No load
Vout to Vdd or Vss
10
20
1
500
Condition
Min
4.75
Typ.
5.0
Max
5.25
5
Units
V
mA
kOhm
nF
nF
kHz
µs
µs
PERFORMANCE CHARACTERISTICS
Parameter
Measuring range
(2
Measuring direction relative to
mounting plane
(12
Zero point
(3,12
Sensitivity
(4,12
Zero point error over temperature
(5
Sensitivity error over
Typical non-linearity
(7
Cross-axis sensitivity
(10
Frequency response –3dB
(8
Ratiometric error
(9
Condition
Nominal
See note 12.
Mounting position
@ room temperature
-25…85 °C typical
-40…125 °C
temperature
(6
-25…85 °C typical
-40…125 °C
Over measuring range
@ room temperature
@ -40…125 °C
Vdd = 4.75...5.25 V
From DC...100 Hz
FS
SCA1000-D01 SCA1020-D02
±1.7
“X”= parellel
“Y” =parallel
Vdd/2
1.2
±70
±100
±3
±4
±20
3.5
50±30 Hz
2
80
11
±1.7
“Z”= perpendicular
“Y”= parallel
Vdd/2
1.2
±70
±100
±3
±4
±20
3.5
50±30 Hz
2
80
11
Units
g
V
V/g
mg
mg
%
%
mg
%
Hz
%
µg/
Hz
Bits
Output noise density
(11
Digital output resolution
VDD = 5.00V, UNLESS OTHERWISE SPECIFIED
Note 1
Note 2
Note 3
Note 4
Note 5
Note 6
Note 7
Note 8
100 nF supply by-pass capacitor is needed.
Measuring directions in parallel to mounting plane, arrows showing positive acceleration
direction.
Zero point specified as Voffset = Vout(0 g) [ V ]. See note 12.
Sensitivity specified as Vsens = {Vout(+1 g) - Vout(-1 g)}/2 [ V/g ]. See note 12.
Zero point error specified as Zero point error = {Vout(0 g) – Vdd/2} / Vsens [ g ] VSens =
Nominal sensitivity Vdd/2 = Nominal offset.
Sensitivity error specified as Sensitivity error = { [Vout(+1 g)-Vout(-1 g)] / 2 - Vsens_nom} /
Vsens_nom x 100 % [% ] Vsens_nom = nominal sensitivity See note 12.
From straight line through +1 g and -1 g points.
The output has true DC (0 Hz) response.
Note 9
Vout(@Vx) x
5.00
V
Vx
The ratiometric error is specified as:
RE =
100%
x
1-
Vout(@
5
V)
The cross-axis sensitivity determines how much acceleration, perpendicular to the measuring
axis, couples to the output. The total crossaxis sensitivity is the geometric sum of the
sensitivities of the two axis which are perpendicular to the measuring axis. The angular
alignment error between channels 1 and 2 is included into the cross axis error.
Typical figure. In addition, supply voltage noise couples to the output due to the
ratiometric nature of the accelerometer.
Measuring directions.
Note 10
Note 11
Note 12
Rev. 18 Jan 2005
VTI Technologies reserves the right to modify this specification without prior to notice.
VTI [ VTI TECHNOLOGIES ]
