Rev. 18 Jan 2005

VTI Technologies reserves the right to modify this specification without prior to notice.

Vout(@Vx) x

5.00

V

Vx

1-

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

Note 1

100 nF supply by-pass capacitor is needed.

Note 2

Measuring directions in parallel to mounting plane, arrows showing positive acceleration

direction.

Note 3

Zero point specified as Voffset = Vout(0 g) [ V ]. See note 12.

Note 4

Sensitivity specified as Vsens = {Vout(+1 g) - Vout(-1 g)}/2 [ V/g ]. See note 12.

Note 5

Zero point error specified as Zero point error = {Vout(0 g) – Vdd/2} / Vsens [ g ] VSens =

Nominal sensitivity Vdd/2 = Nominal offset.

Note 6

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.

Note 7

From straight line through +1 g and -1 g points.

Note 8

The output has true DC (0 Hz) response.

Note 9

The ratiometric error is specified as:

Note 10

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.

Note 11

Typical figure. In addition, supply voltage noise couples to the output due to the

ratiometric nature of the accelerometer.

Note 12

Measuring directions.

For customized product, please contact VTI Technologies

ELECTRICAL CHARACTERISTICS

Parameter

Condition

Min

Typ.

Max

Units

4.75

5.0

5.25

V

Current consumption

Vdd = 5 V; No load

5

mA

Analog resistive output load

Vout to Vdd or Vss

10

kOhm

Analog capacitive output load

20

nF

Digital output load

@ 500 kHz

1

nF

SPI clock frequency

500

kHz

AD conversion time

150

µs

Data transfer time

@500 kHz clock

38

µs

PERFORMANCE CHARACTERISTICS

Parameter

Condition

SCA1000-D01 SCA1020-D02

Units

Nominal

±1.7

±1.7

g

Measuring direction relative to

See note 12.

“X”= parellel

“Y” =parallel

“Z”= perpendicular

“Y”= parallel

Mounting position

Vdd/2

Vdd/2

V

@ room temperature

1.2

1.2

V/g

-25…85 °C typical

±70

±70

mg

-40…125 °C

±100

±100

mg

-25…85 °C typical

±3

±3%

-40…125 °C

±4

±4%

Over measuring range

±20

±20

mg

@ room temperature

3.5

3.5

%

@ -40…125 °C

50±30 Hz

50±30 Hz

Hz

Vdd = 4.75...5.25 V

2

2

%

From DC...100 Hz

80

80

µg/ Hz

Digital output resolution

FS

11

11

Bits

VDD = 5.00V, UNLESS OTHERWISE SPECIFIED

Preliminary