SCA8X0/21X0/3100 Series

VTI Technologies Oy

2/35

www.vti.fi

Doc. Nr. 82 694 00 C

TABLE OF CONTENTS

Table of Contents .....................................................................................................................2

General Description..................................................................................................................5

1.1

Introduction ................................................................................................................................5

1.2

Features ......................................................................................................................................5

1.3

Typical applications...................................................................................................................6

1.4

Functional Description ..............................................................................................................6

1.4.1

Sensing element ...................................................................................................................................6

1.4.2

Interface IC............................................................................................................................................6

1.4.3

Capacitance to voltage conversion.......................................................................................................6

1.4.4

Analog to digital conversion..................................................................................................................7

1.4.5

Signal conditioning and filtering ............................................................................................................7

1.4.6

Temperature measurement ..................................................................................................................7

1.4.7

Memory .................................................................................................................................................7

1.4.8

SPI ........................................................................................................................................................7

1.4.9

Self diagnostics.....................................................................................................................................7

1.4.10

Power supply interface..........................................................................................................................7

1.4.11

Factory calibration.................................................................................................................................7

2

Operation Modes .................................................................................................................8

2.1

Measurement mode ...................................................................................................................8

2.2

Temperature output ...................................................................................................................8

2.3

Self-diagnostic functions ..........................................................................................................8

2.3.1

Memory self-diagnostic .........................................................................................................................8

2.3.2

Signal path self-diagnostic....................................................................................................................8

2.3.2.1

SCA8X0 – single axis accelerometers ..........................................................................................8

2.3.2.2

SCA21X0 and SCA31X0 – multi axis accelerometers ..................................................................8

2.4

Power Down mode.....................................................................................................................9

2.5

Recommended start-up sequence ...........................................................................................9

2.6

Recommended operation sequence ......................................................................................10

2.7

Recommended procedures or optional features ..................................................................11

2.7.1

SCA8x0/SCA21x0/SCA31x0 ..............................................................................................................11

2.7.1.1

Read back procedure ..................................................................................................................11

2.7.1.2

Checksum during operation.........................................................................................................11

2.7.1.3

Saturated data .............................................................................................................................11

2.7.1.4

Noiseless output ..........................................................................................................................11

2.7.1.5

Component ID..............................................................................................................................11

2.7.2

SCA8x0 ...............................................................................................................................................11

2.7.2.1

Mass deflection during operation.................................................................................................11

2.7.2.2

Monitor acceleration data during mass deflection .......................................................................12

3

Addressing Space .............................................................................................................12

3.1

Output registers .......................................................................................................................12

3.1.1

X axis acceleration output...................................................................................................................12

3.1.1.1

X_LSB..........................................................................................................................................12

3.1.1.2

X_MSB.........................................................................................................................................13

3.1.2

Y axis acceleration output...................................................................................................................13

3.1.2.1

Y_LSB..........................................................................................................................................13