VTI SCA100T

SCA100T Series
Inclinometer
FEATURES
• 2-axis inclination measurement (X and Y)
• Available ranges ±0.5 g (±30 °), ±1.0 g (±90 °)
• Over damped frequency response by Sensing Element
(-3 dB @ 8...28 Hz)
• 0.003 ° resolution (10 Hz BW, analog output)
• Advanced internal and external connection failure detection
• Digitally activated electrostatic sensing element self test
• Continuous memory parity check
• Single +5 V supply; ratiometric voltage output
• Serial Peripheral Interface (SPI) compatible
• Internal temperature sensor, accessible via SPI
• Lead-free reflow solderable lead-free component
BENEFITS
• Excellent reliability and stability over time
and temperature
• Instrumentation grade performance
• High resolution and low noise
• Wide temperature range
• Outstanding overload and shock durability
APPLICATIONS
• 2-axis platform levelling
• Inclination based position measurement
• Tilt measurement with cross-axis compensation
• 360 ° vertical orientation measurement
ELECTRICAL CHARACTERISTICS
Parameter
Condition
Supply voltage Vdd (1
Current consumption
Vdd = 5 V; No load
Analogue output load
Vout to Vdd or Vss
Min
Typ.
Max
4.75
5.0
5.25
V
4
5
mA
10
Units
kOhm
20
Digital output load
@ 500 kHz clock
SPI clock frequency
AD conversion time
Data transfer time
@500 kHz clock
nF
1
nF
500
kHz
150
µs
38
µs
PERFORMANCE CHARACTERISTICS
SCA100T-D01
(±30 °)
SCA100T-D02
(±90 °)
±30
±0.5
±90
±1
Mounting plane horizontal
Dual axis inclination
Dual axis inclination
Mounting plane vertical
Orthogonal rotation
Orthogonal rotation
Vdd/2
Parameter
Condition
Measuring range (2
Nominal
Measuring direction (3
Units
°
g
Zero point (4
Mounting position
Vdd/2
V
Sensitivity
@ room temperature
4(5a
2(5b
V/g
Offset calibration accuracy (6a, 13
@ room temperature
0...70 °
±2
±5
±10
±15
±0.5
±4
±5
±10
±15
±0.5
mg
Offset temperature dependency (6b, 13
%
-25…85 °C
-40…125 °C
mg
mg
mg
Sensitivity calibration accuracy (7a, 13
@ room temperature
Sensitivity temperature error (7b, 13
-40…85 °C
-1...1
-1...1
85…125 °C
-2.5...1
-2.5...1
%
±2
±10
mg
%
Typical non-linearity (8
Over measuring range
Cross-axis sensitivity (11
@ room temperature
4
4
%
Frequency response –3 dB (LP) (9
@ room temperature
8…28
8…28
Hz
Vdd = 4.75...5.25 V
±2
±2
%
From DC...100 Hz
15
15
µg/ Hz
11
11
Bits
0.25
T.B.D
mg
Ratiometric error
(10
Output noise density (12
Digital output resolution
FS
Long term stability (14
@ steady temp
VDD = 5.00 V, APPLIES TO BOTH CHANNELS UNLESS OTHERWISE SPECIFIED
Note 1
Note 2
Note 3
Note 4
Note 5a
Note 5b
Note 6a
Note 6b
Note 7a
Note 7b
For maximum accuracy the supply voltage should be 5 ±0.05 V. 100 nF supply filtering capacitor
is recommended.
The measuring range is limited by sensitivity, offset and supply voltage rails of the device.
Measuring directions in parallel to mounting plane, arrows showing positive acceleration direction
Offset specified as Voffset = Vout(0 g) [ V ]. See note 12.
Sensitivity specified as Vsens = {Vout(+0.5 g) - Vout(-0.5 g)}/1 [ V/g ]. See note 12.
Sensitivity specified as Vsens = {Vout(+1 g) - Vout(-1 g)}/2 [V/g ]. See note 12.
Offset calibration error specified as Offset_Calib_error = {Vout(0 g) – Vdd/2} / Vsens [ g ].
Offset temperature error specified as Offset Error @ temp. = {Vout @ temp. – Vout @ room temp.}
/ Vsens [ g ].
Sensitivity calibration error specified as Sensitivity_calibr_error = { Vsens - Vsens_nom} /
Vsens_nom x 100 % [%] Vsens_nom = nominal sensitivity.
Sensitivity temperature error specified as Sensitivity error @ temp = { [Vsens @ temp –Vsens
@ room temp] / Vsens @ room temp x 100 % [% ].
Rev. 2 / 15 Sept 2005
Note 8
Note 9
From straight line through sensitivity calibration point.
The output has true DC (0 Hz) response.
Note 10
The ratiometric error is specified as:
Note 11
The cross-axis sensitivity determines how much inclination / 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.
In addition, supply voltage noise couples to the output due to the ratiometric nature of the
accelerometer.
Factory calibration value.
Power continuously connected.
Note 12
Note 13
Note 14
VTI Technologies reserves the right to modify this specification without prior to notice.
SCA100T Series
MEASURING DIRECTIONS
ABSOLUTE MAXIMUM RATINGS
Parameter
Value
Acceleration (powered or non-powered)
20 000
Unit
g
Supply voltage
-0.3 V to +5.5 V
V
Voltage at input/output pins
-0.3 V to (Vdd+0.3 V)
V
Temperature range
-55…125
°C
ELECTRICAL CONNECTION
RECOMMENDED CIRCUIT
Pin#
Pin Name
I/O
1
SCK
Input
Connection
Serial clock
2
Ext_C_1
Input
X axis external capacitor input (Ch 1)
3
MISO
Output
Master in slave out; data output
4
MOSI
Input
Master out slave in; data input
5
Out_2
Output
Y axis Output (Ch 2)
6
GND
Power
round (GND)
7
CSB
Input
Chip select (active low)
8
Ext_C_2
Input
Y axis external capacitor input (Ch 2)
9
ST_2
Input
Self test input for Y axis (Ch 2)
10
ST_1 / Test_in
Input
Self test input for X axis (Ch 1 )
11
Out_1
Output
X axis output (Ch 1)
12
VDD
Power
Positive supply voltage (VDD)
If the SPI interface is not used SCK (pin1), MISO (pin3), MOSI (pin4) and CSB (pin7)
must be left floating.
Self test can be activated applying logic “1” (positive supply voltage level)
to ST pin (pin 9 and 10). If ST feature is not used pins 9 and 10 must be left
floating or connected to GND.
DIMENSIONS
PCB PAD LAYOUTS
The part weights under 1.2 g. The size is appr. (w x h x l) 9 x 5 x 16 mm. Pin pitch is standard 100 mils.
Acceleration in the direction of the arrow will
increase the output voltage.
VTI Technologies Oy
Myllynkivenkuja 6
P.O. Box 27
FI-01621 Vantaa
Finland
Tel. +358 9 879 181
Fax +358 9 879 18791
[email protected]fi
VTI Technologies Oy
Frankfurt Branch
Rennbahnstr. 72-74
D-60528 Frankfurt am Main
Germany
Tel. +49 69 6786 880
Fax +49 69 6786 8829
[email protected]fi
VTI Technologies, Inc.
One Park Lane Blvd.
Suite 804 - East Tower
Dearborn, MI 48126
USA
Tel. +1 313 425 0850
Fax +1 313 425 0860
[email protected]