SCA3000-D02 - Murata Electronics North America

Doc.Nr. 8257300A.07

Product Family Specification

SCA3000 Series

3-axis accelerometer

SCA3000 Series

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TABLE OF CONTENTS

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

1.1 Introduction................................................................................................................................5

1.2 Functional Description..............................................................................................................5

1.2.1 Sensing element..................................................................................................................5

1.2.2 Interface IC...........................................................................................................................5

1.2.3 Factory calibration..............................................................................................................6

1.2.4 Supported features .............................................................................................................6

1.2.5 Operation modes.................................................................................................................6

1.2.5.1 Measurement................................................................................................................................6

1.2.5.2 Motion Detection..........................................................................................................................6

1.2.6 Free-Fall Detection..............................................................................................................6

1.2.7 Interrupt................................................................................................................................7

1.2.8 Temperature output ............................................................................................................7

1.2.9 Output ring buffer................................................................................................................7

2 Reset and power up, Operation Modes, HW functions and Clock.................................7

2.1 Reset and power up...................................................................................................................7

2.2 Measurement Mode ...................................................................................................................7

2.2.1 Description...........................................................................................................................7

2.2.1.1 Bypass measurement mode.......................................................................................................8

2.2.1.2 Narrow band measurement mode..............................................................................................8

2.2.1.3 Wide band measurement mode .................................................................................................8

2.2.2 Usage....................................................................................................................................8

2.2.2.1 Overflow condition......................................................................................................................8

2.3 Motion Detection Mode .............................................................................................................9

2.3.1 Description...........................................................................................................................9

2.3.2 Usage..................................................................................................................................10

2.3.3 Examples............................................................................................................................10

2.4 Free-Fall Detection...................................................................................................................11

2.4.1 Description.........................................................................................................................11

2.4.2 Usage..................................................................................................................................11

2.4.3 Example..............................................................................................................................11

2.5 Ring Buffer ...............................................................................................................................12

2.5.1 Description.........................................................................................................................12

2.5.2 Usage..................................................................................................................................12

2.5.2.1 Overflow condition....................................................................................................................12

2.5.3 Examples............................................................................................................................13

2.6 Temperature measurement.....................................................................................................13

2.6.1 Usage..................................................................................................................................13

2.7 Interrupt function (INT-pin).....................................................................................................13

2.7.1 Usage..................................................................................................................................13

2.8 Clock.........................................................................................................................................14

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3 Addressing Space............................................................................................................ 15

3.1 Register Description................................................................................................................15

3.2 Non-volatile memory ...............................................................................................................16

3.3 Output Registers......................................................................................................................16

3.4 Configuration Registers..........................................................................................................19

4 Serial Interfaces ...............................................................................................................24

4.1 SPI Interface.............................................................................................................................24

4.1.1 SPI frame format................................................................................................................24

4.1.2 SPI bus error conditioning ...............................................................................................25

4.1.3 Examples of SPI communication.....................................................................................25

4.1.3.1 Example of register read...........................................................................................................25

4.1.3.2 Example of decremented register read...................................................................................26

4.1.3.3 Example of ring buffer read......................................................................................................26

4.2 I2C Interface..............................................................................................................................27

4.2.1 I2C frame format.................................................................................................................27

4.2.1.1 I2C write mode................................................................................................................... .........27

4.2.1.2 I2C read mode.............................................................................................................................27

4.2.1.3 Decremented register read.......................................................................................................27

4.2.2 Examples of I2C communication......................................................................................28

5 Electrical Characteristics ................................................................................................ 29

5.1 Absolute maximum ratings.....................................................................................................29

5.2 Power Supply...........................................................................................................................29

5.3 Digital I/O Specification...........................................................................................................29

5.3.1 Digital I/O DC characteristics...........................................................................................29

5.3.2 Digital I/O level shifter.......................................................................................................29

5.3.3 SPI AC characteristics......................................................................................................30

5.3.4 I2C AC characteristics.......................................................................................................31

6 Package Characteristics.................................................................................................. 31

6.1 Dimensions...............................................................................................................................31

7 Application information................................................................................................... 32

7.1 Pin Description.........................................................................................................................32

7.2 Recommended circuit diagram ..............................................................................................32

7.3 Recommended PWB layout....................................................................................................33

7.4 Assembly instructions ............................................................................................................35

7.5 Tape and reel specifications...................................................................................................35

8 Data sheet references......................................................................................................36

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8.1 Offset.........................................................................................................................................36

8.1.1 Offset calibration error .....................................................................................................36

8.1.2 Offset temperature error...................................................................................................36

8.2 Sensitivity.................................................................................................................................37

8.2.1 Sensitivity calibration error..............................................................................................37

8.2.2 Sensitivity temperature error...........................................................................................37

8.3 Linearity....................................................................................................................................38

8.4 Noise.........................................................................................................................................39

8.5 Bandwidth.................................................................................................................................39

8.6 Cross-axis sensitivity..............................................................................................................39

8.7 Turn-on time.............................................................................................................................40

9 Order Information............................................................................................................. 41

10 Document Change Control.............................................................................................. 42

11 Contact Information.........................................................................................................43

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1 General Description

1.1 Introduction

SCA3000 is a three axis accelerometer family targeted for products requiring high performance

with low power consumption. It consists of a 3D-MEMS sensing element and a signal conditioning

ASIC packaged into a plastic Molded Interconn ection Device package (MID).

A block diagram of the SCA3000 product family is prese nted in Figure 1 below.

INT

DE-

MUX

1:3

Low-pass

Filter

Low-pass

Filter

Low-pass

Filter

Decimation

Coordinate

Mapping

and

Calibration

Oscillator

&

clock

Motion

detector Free fall

detector

Reference

SPI

&

I2C

i/f

Control

&

INT

SCK/SCL

MISO/SDA

MOSI

CSB

Ring

Buffer

C/V

Analog

calibration

&

ADC

Non-

Volatile

Memory

Temperature

sensor

Figure 1. SCA3000 Block Diagram.

This document, no. 8257300, describes the product specification (e.g. operation modes, user

accessible registers, electrical properties and application information) for the SCA3000 family. The

specification for an individual sensor is av ailable in the corresponding data sheet.

1.2 Functional Description

1.2.1 Sensing element

The sensing element is manufactured using the proprietary bulk 3D-MEMS process, which enables

robust, stable and low noise & power ca pacitive sensors.

The sensing element consists of three acceleration sensitive masses. Acceleration will cause a

capacitance change that will be then converted into a voltage change in the signal conditioning

ASIC. Due to its mechanical construction, the element's measurement coordinates are rotated 45°

compared to the conventional orthogona l X,Y,Z coordinate system.

1.2.2 Interface IC

The sensing element is interfaced via a capacitance-to-voltage (CV) converter. Following

calibration in the analog domain, the signal is converted by a successive approximation type of

analog-to-digital converter (ADC). The ADC's signal is de-multiplexed into three signal processing

channels where it is low-pass filtered and decimated. After that, the signals are mapped into

orthogonal coordinates (X-Y-Z) and transferred to the output registers. Depending on the product,

the SCA3000 sensor supports either a fully digital serial SPI or I2C interface. In normal

measurement mode, acceleration data can be read via the serial bus. Other supported features are

a separate motion detection mode and parallel free-fall detection. In these modes, the sensor will

generate an interrupt when a pre-defined condition has been met.

The SCA3000 includes an internal oscillator, reference and non-volatile memory that enable the

sensor's autonomous operation within a system. The temperature sensor is used in some product

applications to enhance the temperature stability. In that case, temperature information can also be

read out from the device.

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1.2.3 Factory calibration

Sensors are factory calibrated and the trimmed parameters are gain, offset and the frequency of

the internal oscillator. Calibration parameters will be read automatically from the internal non-

volatile memory during sensor startup.

1.2.4 Supported features

Features supported by individual SCA3000 products are listed in Table 1 below.

Table 1. SCA3000 devices’ summary.

Features SCA3000-D01 (SPI) /

SCA3000-D02 (I2C) SCA3000-E01 (SPI) /

SCA3000-E02 (I2C) SCA3000-E04 SCA3000-E05

Supply

voltage 2.35 V – 3.6 V 2.35 V – 3.6 V 2.35 V – 3.6 V 2.35 V – 3.6 V

I/O voltage 1.7 V – 3.6 V 1.7 V – 3.6 V 1.7 V – 3.6 V 1.7 V – 3.6 V

Measuring

range ±2 g ±3 g ±6 g ±18 g

Resolution 0.75mg / 0.04° 1mg / 0.06° 2mg / 0.11° 6.25mg / 0.36°

Sensitivity 1333 counts/g 1000 counts/g 500 counts/g 160 counts/g

Output

buffer User enabled,

64 sampl./axis User enabled,

64 sampl./axis

Motion

detection User enabled User enabled User enabled User enabled

Free fall

detection User enabled User enabled User enabled User enabled

Interface SPI max 1.6 MHz (-D01) /

I2C fast mode (-D02) SPI max 325 kHz (-E01) /

I2C std mode (-E02) SPI max 325 kHz SPI max 325 kHz

Temperatu

re output Yes No No No

Clock Internal Internal Internal Internal

1.2.5 Operation modes

1.2.5.1 Measurement

The SCA3000 is in normal measurement mode by default after start up. The sensor offers

acceleration information via the SPI or I2C when the master requires it. The master can acquire one

axis acceleration or all three axis acceleration depending on the application. Measurement

resolution depends on the product type (see Table 1).

1.2.5.2 Motion Detection

Motion Detection (MD) mode is intended to be used to save system level power consumption. In

this mode, the SCA3000 activates the interrupt via the INT-pin when motion is detected. Sensitivity

levels can be configured via the SPI or I2C bus for each axis. Moreover, the detection condition can

be defined using sensitivity directions with AND / OR / mux logic. Once the interrupt has happened,

the detected direction can be read out from the co rresponding status register.

Normal acceleration information is not av ailable in MD mode.

1.2.6 Free-Fall Detection

Free-Fall Detection (FFD) is intended to be used to save system resources. This feature activates

the interrupt via the INT-pin when free-fall is detected. The minimum detectable distance depends

on the individual product. Normal acceleration information is available when the FFD is enabled.

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1.2.7 Interrupt

The SCA3000 has a dedicated output pin (INT) to be used as the interrupt for the master controller.

Interrupt conditions can be activated and deactivated via the SPI or I2C bus. Once the interrupt has

happened, the interrupt source can be read out from the corre sp onding status register.

1.2.8 Temperature output

Some SCA3000 products provide 9-bit temperature information via the serial interface. See Table 1

for detailed product information.

1.2.9 Output ring buffer

In those applications where real time acceleration information is not needed, the ring buffer

memory can be used to buffer acceleration data. This will release µC resources for other tasks or

for example, to offer a power saving mode while SCA3000 samples acceleration data into its buffer

memory.

Acceleration data is sampled at a constant sample rate by the sensor. The buffer is a FIFO type

(First In First Out) where the oldest data is shifted out first. It has separate read and write address

pointers, so it can be read and written simultaneously. If the buffer overflows, the oldest data is lost

and the new data replaces the oldest samples.

Ring buffer logic can be configured to give an interrupt when the buffer is ½ or ¾ full. The entire

ring buffer content can be read by one read sequence.

2 Reset and power up, Operation Modes, HW functions and Clock

2.1 Reset and power up

The SCA3000 has an external active low reset pin. Power supplies must be within the specified

range before the reset can be released.

After releasing the reset, the SCA3000 will read configuration and calibration data from the non-

volatile memory to volatile registers. Then the SCA3000 will make a check sum calculation to the

read memory content. The STATUS register's CSME-bit="0" shows successful memory read

operation.

2.2 Measurement Mode

2.2.1 Description

The SCA3000 enters the measurement mode by default after power-on and the CV-converter will

start to feed data to the signal channel (Figure 1). Data will be reliable in the output registers after

the product specific turn-on time.

The SCA3000 can also be set to optional measurement modes. See component specific data

sheets for detailed functional parameters in all measurement modes. All available measurement

modes for the SCA3000 are described in Table 2 below.

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Table 2. Available measurement modes for SCA3000.

Available measurement

modes SCA3000-D01

SCA3000-D02 SCA3000-E01

SCA3000-E02 SCA3000-E04 SCA3000-E05

Default after power-on

or reset Measurement

mode Measurement

mode

Optional measurement

mode 1

Bypass

measurement

mode

Narrow band

measurement

mode

Narrow band

measurement

mode

Narrow band

measurement

mode

Optional measurement

mode 2 Not available Not available Wide band

measurement

mode

Wide band

measurement

mode

2.2.1.1 Bypass measuremen t mode

In bypass measurement mode, the signal bandwidth of the SCA3000 is extended by bypassing the

low-pass filter in signal channel. As a result of a wider measurement bandwidth, the noise level is

higher.

2.2.1.2 Narrow band measurement mode

In narrow band measurement mode, the signal bandwidth of the SCA3000 is reduced by increasing

low-pass filtering in signal channel. In addition, the output data rate is halved due to decimation. As

a result of a narrower signal bandwidth, the noise level is lower.

2.2.1.3 Wide band measurement mode

In wide band measurement mode, the SCA3000 signal channel low-pass filtering pass band is

widened. As a result of a wider measur ement bandwidth, the noise level is higher.

2.2.2 Usage

The optional measurement modes can be enabled by setting the bits called MODE_BITS in MODE

register to "010" or "001". See section 3. 4 for MODE register details.

Acceleration data can be read from data output registers X_LSB, X_MSB, Y_LSB, Y_MSB, Z_LSB

and Z_MSB in all measurement modes. Each of these registers can be read one by one or using

the decrement register read, which is described in section 4.1.3.2 for SPI and 4.2.1.3 for I2C

interface. See section 3.3 for output register details.

2.2.2.1 Overflow condition

Since acceleration data registers have no limiter, the possible overflow needs to be detected using

bits [B7, B6, B5]. If bits [B7, B6, B5] are ‘011’ or ‘100’, data overflow has occurred (see Table 3).

This applies for all acceleration output registers (X_L SB … Z_MSB and BUF_DATA).

Table 3. Overflow bit patterns in acceleration data registers (X_LSB … Z_MSB and BUF_DAT A ).

Byte MSB byte LSB byte

Bit number

Acceleration data bit B7

Sign B6

d11 B5

d10 B4

d9 B3

d8 B2

d7 B1

d6 B0

d5 B7

d4 B6

d3 B5

d2 B4

d1 B3

d0 B2:B0

Data overflow on

positive acceleration 0 1 1 x x x x x x x x x x xxx

Data overflow on

negative

acceleration 1 0 0 x x x x x x x x x x xxx

x = ignore

In case of overflow, the output register value must be discarded. When an overflow is detected, the

bit pattern ‘0101 1111 1111 1xxx’ is used for positive accelerations and ‘1010 0000 0000 0xxx’ for

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negative accelerations until a valid acceleration value is read. In Table 4 the maximum and

minimum acceleration register values that are in measuring range (for registers X_LSB … Z_MSB)

for SCA3000-D0x and SCA3000-E0x are presented.

Table 4. Maximum and minimum values in the SCA3000 measu ring range.

SCA3000-D01

SCA3000-D02 SCA3000-E01

SCA3000-E02 SCA3000-E04 SCA3000-E05

First positive

acceleration value

out of range

[mg]

dec

bin

-

3072

0110 0000 0000 0xxx

-

3072

0110 0000 0000 0xxx

-

3072

0110 0000 0000 0xxx

-

3072

0110 0000 0000 0xxx

Maximum positive

acceleration value

in range

[mg]

dec

bin

2303.25 mg

3071

0101 1111 1111 1xxx

3071 mg

3071

0101 1111 1111 1xxx

6142 mg

3071

0101 1111 1111 1xxx

19193.75 mg

3071

0101 1111 1111 1xxx

Minimum negative

acceleration value

in range

[mg]

dec

bin

-2304 mg

-3072

1010 0000 0000 0xxx

-3072 mg

-3072

1010 0000 0000 0xxx

-6144 mg

-3072

1010 0000 0000 0xxx

-19200 mg

-3072

1010 0000 0000 0xxx

First negative

acceleration value

out of range

[mg]

dec

bin

-

-3073

1001 1111 1111 1xxx

-

-3073

1001 1111 1111 1xxx

-

-3073

1001 1111 1111 1xxx

-

-3073

1001 1111 1111 1xxx

2.3 Motion Detection Mode

2.3.1 Description

In MD mode, the ADC's data is not fed to the signal processing channel shown in Figure 1 but to

the MD block. It consists of a digital band-pass filter (BPF), threshold level programmable digital

comparator and a configurable trigger fu nction.

BPF's -3 dB low-pass frequency is 25 Hz …60 Hz and -3 dB high-pass frequency is

0.05 Hz …1 Hz. See Figure 2 below.

Band Pass Filter's Response

for referenc e onl y

-20

-15

-10

-5

0

5

0.01 0.1 1 10 100 1000

Freq [Hz]

Atten u a t io n [d B]

Lower limit

Upp er li mit

Figure 2. The MD band-pass filter's frequency response.

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The absolute value of programmable Threshold Level (TL) is 0 < |TL| < FS g (FS is sensor full

scale measuring range). NOTE: Due to power consumption optimization, the step size between

each step and axis is not the same, see section 3.4 for thresh old level details.

The triggering condition can be defined using OR/AND logic:

1. Any sensing direction can be configured to trigger the interrupt (OR condition).

2. Any sensing direction can be configured to be required to trigger the interrupt (AND condition).

+TL

Accelerat ion ex ceeds

the threshold level

due to motion

-TL

Acceleration

X, Y or Z

T1 T2 T3 T4 T5 T6 T7 T8 Time

INT output

"1"

"0"

Figure 3. Motion detector operation.

2.3.2 Usage

The MD mode can be enabled by setting the MODE bits in the MODE register to "011". The trigger

condition can be defined by setting REQ_Z, REQ_Y, REQ_X, EN_Z, EN_Y and EN_X bits in

MD_CTRL register and Z_TH, Y_TH and Z_TH bits in MD_Z_TH, MD_Y_TH and MD_X_TH

registers, respectively. See section 3.4 for the configuration register and section 2.7 for the

interrupt functionality details.

In MD mode, acceleration data is not available in registers X_LSB, X_MSB, Y_LSB, Y_MSB,

Z_LSB, Z_MSB and BUF_DATA.

2.3.3 Examples

A simple example of motion detection usage:

1. Write "00000011" (03h) into the MODE register (enable motion detection mode,

MODE_BITS = '011').

2. Acceleration data is not available when the SCA3000 is in motion detection mode.

3. The INT-pin is activated when motion is detected, see section 2.7 for detailed INT-pin

information.

In the next example, the motion detector is configured to give an interrupt on motion only in the X-

OR Y-axis direction:

1. Write "00000011" (03h) into MODE register (enable motion detection mode,

MODE_BITS = '011')

2. Write "00000000" (00h) into UNLOCK register

3. Write "01010000" (50h) into UNLOCK register

4. Write "10100000" (A0h) into UNLOCK register

5. Write "00000010" (02h) into CTRL_SEL register (to select indirect MD_CTRL register)

Unlock sequence for register lock

6. Write "00000011" (03h) into CTRL_DATA register (this data is written into MD_CTRL

register, enable trigger on Y-channel, EN_Y = '1', enable trigger on X-channel, EN_X = '1')

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7. Acceleration data is not available when the SCA3000 is in motion detection mode

8. The INT-pin is activated when motion is detected in the X- or Y-axis direction (Z-axis

direction is ignored), see section 2.7 for detailed INT -pin information.

2.4 Free-Fall Detection

2.4.1 Description

During free-fall in the gravitation field, all 3 orthogonal acceleration components are ideally equal to

zero. Due to practical non-idealities, detection must be done using Threshold Level (TL) greater

than 0.

When enabled, the Free-Fall Detection (FFD) will monitor 8 MSB's of the measured acceleration in

the X, Y and Z directions. If the measured acceleration stays within the TL longer than time TFF

(Figure 4 below), which corresponds approx 25 cm drop distance, the FFD will generate an

interrupt to the INT-pin.

T1 T2 T3 T4 T5 T6 T7 T8

+TL

TFF

-TL

Acceleration

X, Y and Z

Time

T1 T2 T3 T4 T5 T6 T7 T8 Time

INT output

"1"

"0"

Figure 4. Free Fall condition.

2.4.2 Usage

Free-fall detection can be enabled by setting FFD_EN bit in MODE register to "1". See section 3.4

for MODE register details.

Acceleration data is available in registers X_LSB, X_MSB, Y_LSB, Y_MSB, Z_LSB, Z_MSB and

BUF_DATA as in measurement mode. See section 3.3 for output register and section 2.7 for

interrupt functionality details.

2.4.3 Example

A simple example of free-fall detection usage:

1. Write "00010000" (10h) into the MODE register (enable free fall detection, FFD_EN = '1')

2. Acceleration data can be read normally

3. INT-pin is activated when free fall is detected, see section 2.7 for detailed INT-pin

information.

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2.5 Ring Buffer

2.5.1 Description

The SCA3000's Ring Buffer is a 192 acceleration data samples long (64 samples of 11 bit three

axis data) internal memory to relax the real-time operation requirements of the host processor. The

following parameters are configurable:

1. Each measurement axis can be individually disabled. If measurement data from e.g. Y-axis

is not needed, available memory can be used for X- a nd Z-axis data.

2. Buffer data length can be changed from 11 to 8 bits. In 8-bit mode, data can be read out

using shorter read sequence.

3. Ring buffer's input sample rate can be the same as the sensor's data rate or divided by 2

or 4. When the divider is e.g. 2, only every 2nd acceleration data will be stored.

4. The Interrupt condition, when enabled, can be selected between two: interrupt in INT-pin

occurs when the buffer is 50% or 75% full.

2.5.2 Usage

The ring buffer can be enabled by setting BUF_EN bit in MODE register to "1". After enabling the

buffer, acceleration data can be read from BUF_DATA register using decrement register read,

which is described in section 4.1.3.2 for SPI and 4.2.1.3 for I2C interface.

Each measurement axis can be individually disabled by setting corresponding bits in BUF_X_EN,

BUF_Y_EN and BUF_Z_EN in OUT_CTRL register to "0".

Output data length can be changed from 11 bits to 8 bits by setting bit BUF_8BIT in MODE register

to "1". See section 3.3 for bit level descriptions.

The count of available data samples in output ring buffer can be read from BUF_COUNT register.

Register value is updated only when it is accessed over the SPI or I2C.

Data shift out order is X,Y,Z. In 11 bit mode two bytes must be read to get all 11 bits out. In that

case, the MSB byte is 1st. Examples:

1. 11 bits data length, X&Y&Z axis enabled:

X1_MSB, X1_LSB, Y1_MSB, Y1_LSB, Z1_MSB, Z1_LSB, X2_MSB, X2_LSB, ... latest

Z_LSB

2. 11 bits data length, Y&Z axis enabled:

Y1_MSB, Y1_LSB, Z1_MSB, Z1_LSB, Y2_MSB, Y2_LSB, Z2_MSB, Z2_LSB, Y3_MSB,

Y3_LSB, ..., latest Z_LSB

3. 8 bits data length, all axis enabled:

X1, Y1, Z1, X2, Y2, Z2,..., latest Z

4. 8 bits data length, X&Z axis enabled:

X1, Z1, X2, Z2, X3, Z3, ..., latest Z

5. 8 bits data length, Z axis enabled:

Z1, Z2, Z3, ... , latest Z

See section 2.7 for interrupt functionality details.

Acceleration data is available in X_LSB, X_MSB, Y_LSB, Y_MSB, Z_LSB and Z_MSB when the

ring buffer is enabled.

2.5.2.1 Overflow condition

Overflow is detected from data ring buffer in same way as from the output registers. See section

2.2.2.1 for details.

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2.5.3 Examples

A simple example of output ring buffer usage:

1. Write "10000000" (C0h) into MODE register (enable output ring buffer, BUF_EN = '1')

2. Acceleration data can be read normally

3. INT-pin is activated when buffer is ½ full, see section 2.7 for detailed INT-pin information.

In the next example, the output Ring Buffer is configured to sample only the Z-axis acceleration

data with 8 bit resolution and reduced data rate (only every second sample is stored into output

ring buffer). In addition, the SCA3000 is configured to give an interrupt when the output ring buffer

is ¾ full:

1. Write "11000000" (C0h) into the MODE register (enable output ring buffer, BUF_EN = '1',

set data length to 8 bits, BUF_8BIT = '1')

2. Write "00000000" (00h) into UNLOCK register

3. Write "01010000" (50h) into UNLOCK register

4. Write "10100000" (A0h) into UNLOCK register

5. Write "00001011" (0Bh) into CTRL_SEL register (to select indirect OUT_CTRL register)

Unlock sequence for register lock

6. Write "00000101" (03h) into CTRL_DATA register (this data is written into OUT_CTRL

register, store Z-axis data, BUF_Z _EN = '1', divide data rate by 2, BUF_RATE = ' 01')

7. Write "10000001" (81h) into INT_MASK register (set buffer interrupt level to ¾ full,

BUF_F_EN = '1', set INT-pin to active high, INT_ACT = '1')

8. Acceleration data can be read normally for all axis and with full resolution. The buffer data

can be read from BUF_DA TA register

9. INT-pin is activated when the output ring buffer is ¾ full of Z-axis acceleration data, see

section 2.7 for detailed INT-pin informati on.

2.6 Temperature measurement

2.6.1 Usage

Nine bit temperature information is available in the TEMP_MSB and TEMP_LSB registers, if the

feature is enabled in the product (see Table 1). The TEMP_MSB register must be read before the

TEMP_LSB register in order to get valid temperature data. Registers are updated with the latest

temperature data when acce ssed. See section 3.3 for register details.

The temperature registers’ typical output at +23 °C is 256 counts and a 1 °C change in temperature

typically corresponds to a 1.8 LSB change in the SCA3000 temperature output. Temperature

information is converted to [°C] as follows

Equation 1

[]

C

LSB LSBTemp

CCTemp dec

°

−

+°=° 8.1

256

23

where Temp[°C] is temperature in Celsius and Tempdec is the temperature from TEMP_MSB and

TEMP_LSB registers in decimal format.

2.7 Interrupt function (INT-pin)

2.7.1 Usage

The Motion Detector and Free Fall Detector will generate an interrupt to INT-pin when the

corresponding function is enabled and the interrupt condition is met. The SCA3000's ring buffer will

generate an interrupt when interrupt functionality has been enabled. Setting BUF_F_EN bit in

INT_MASK register "1" results in interrupt when the register is 75% full. Setting BUF_H_EN bit in

INT_MASK register "1" results in interrupt when the register is 50% full.

Setting INT_ALL bit in INT_MASK register will mask all interrupts.

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The interrupt polarity (active high/low) can be configured with INT_MASK register's INT_ACT bit.

Once the interrupt has happened, the INT_STATUS register must be read to acknowledge the

interrupt.

1. If at least one of MD bits in INT_STATUS register is "1", motion has been detected.

2. If FFD bit in INT_STATUS register is "1", free-fall has been detected.

3. If BUF_FULL bit is "1", Ring Buffer is 75% full. Correspondingly, if BUF_HALF is "1", the

Ring Buffer is 50% full.

See section 3.3 for INT_STATUS regi ster details.

2.8 Clock

The SCA3000 has an internal factory trimmed oscillator and clock generator. Internal frequencies

vary product by product.

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3 Addressing Space

The SCA3000 register con t ents and bit definitions are described in more detail in the following

sections.

3.1 Register Description

The SCA3000 addressing space is pres ented in Table 5 below.

Table 5. List of registers.

Addr. Name Description Mode

(R, W, RW, IA) Reg.

type Locked

00h REVID ASIC revision ID number R Conf

01h Reserved -

02h STATUS Status register R Conf

03h Reserved -

04h X_LSB X-axis LSB frame R Output

05h X_MSB X-axis MSB frame R Output

06h Y_LSB Y-axis LSB frame R Output

07h Y_MSB Y-axis MSB frame R Output

08h Z_LSB Z-axis LSB frame R Output

09h Z_MSB Z-axis MSB frame R Output

0Ah ... 0Eh Reserved -

0Fh BUF_DATA Ring buffer output register R Output

10h ... 11h Reserved -

12h TEMP_LSB Temperature LSB frame R Output

13h TEMP_MSB Temperature MSB frame R Output

14h MODE Operating mode selection,

control and configuration for:

- mode selection

- output buffer

- free-fall detection

RW Conf

15h BUF_COUNT Count of unread data

samples in output buffer R Output

16h INT_STATUS Interrupt status register:

- output buffer is not full, ½

full or ¾ full

- free-fall detected / not

detected

- information of which axis

triggered motion

R Output

17h I2C_RD_SEL Register address for I2C read

operation RW Conf

18h CTRL_SEL Register address pointer for

indirect control registers RW Conf x

19h

...

1Dh

Reserved -

1Eh UNLOCK Unlock register RW Conf

1Fh ... 20h Reserved -

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Addr. Name Description Mode

(R, W, RW, IA) Reg.

type Locked

21h INT_MASK HW interrupt mask register

(configures the operation of

INT-pin):

- interrupt when output

buffer is ¾ full

(enable / disable)

- interrupt when output

buffer is ½ full

(enable / disable)

- mask all interrupts on

INT-pin (enable / disable )

- INT-pin activity (INT

active low / INT active

high)

RW, NV Conf

22h CTRL_DATA Data to/from register which

address is in CTRL_SEL

(18h) register

RW, NV, IA Conf x

23h ... 3Fh Reserved -

Add. is the register address in hex format.

RW – Read / Write register, R – Read-only register, NV – Register mirrors NV-memory data (NV = non-volatile).

IA – indirect addressing used.

Registers whose read and write access is blocked by register lock is marked in "Locked" column.

3.2 Non-volatile memory

The SCA3000 has an internal non-volati le memory for calibration and co nfiguration data. Memory

content will be programmed during production and is not user configurable. Initial configuration

values can be found in the following se ction 3.4.

3.3 Output Registers

The SCA3000 output registers (marked with 'Output' in Table 5) contents and bit definitions are

described in this section. Output registers contain information of measured acceleration and

temperature as well as information of the operating state and interrupts of SCA3000.

When reading the output values an MSB register must be read first because MSB register reading

latches the data in to all other acceleration output registers

Address: 04h

Register name: X_LSB, X-axis LSB frame

Bits Mode Initial

Value Name Description

7:0 R 00h DATA X-axis LSB frame

Address: 05h

Register name: X_MSB, X-axis MSB frame

Bits Mode Initial

Value Name Description

7:0 R 00h DATA X-axis MSB frame

Address: 06h

Register name: Y_LSB, Y-axis LSB frame

Bits Mode Initial

Value Name Description

7:0 R 00h DATA Y-axis LSB frame

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Address: 07h

Register name: Y_MSB, Y-axis MSB frame

Bits Mode Initial

Value Name Description

7:0 R 00h DATA Y-axis MSB frame

Address: 08h

Register name: Z_LSB, Z-axis LSB frame

Bits Mode Initial

Value Name Description

7:0 R 00h DATA Z-axis LSB frame

Address: 09h

Register name: Z_MSB, Z-axis MSB frame

Bits Mode Initial

Value Name Description

7:0 R 00h DATA Z-axis MSB frame

Address: 0Fh

Register name: BUF_DATA, ring buffer output register

Bits Mode Initial

Value Name Description

7:0 R 00h DATA Ring buffer output register

Bit level description for acceleration data from X_LSB ... Z_MSB and BUF_DATA registers is

presented in Table 6 ... Table 9. Acceleration data is presented in 2's complement format. At 0 g

acceleration the output is ideally 00h.

Table 6. Bit level description for acceleration registers of SCA3000-D01 and SCA3000-D02.

Byte MSB byte LSB byte

Bit number

Acceleration [mg] B7

Sign B6

1536 B5

768 B4

384 B3

192 B2

96 B1

48 B0

24 B7

12 B6

6 B5

3 B4

1.5 B3

0.75 B2:B0

xxx

SCA3000-D01,-D02

[X_LSB…Z_MSB] s d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 xxx

SCA3000-D01,-D02

Ring buffer in 11-bit

mode [BUF_DATA] s d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 x x xxx

SCA3000-D01,-D02

Ring buffer in 8-bit

mode [BUF_DATA] s d6 d5 d4 d3 d2 d1 d0 x x x x x xxx

s = sign bit

x = not used bit

Table 7. Bit level description for acceleration registers of SCA3000 -E01 and SCA3000-E02.

Byte MSB byte LSB byte

Bit number

Acceleration [mg] B7

Sign B6

2048 B5

1024 B4

512 B3

256 B2

128 B1

64 B0

32 B7

16 B6

8 B5

4 B4

2 B3

1 B2:B0

xxx

SCA3000-E01,-E02

[X_LSB…Z_MSB] s d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 xxx

SCA3000-E01,-E02

Ring buffer in 11-bit

mode [BUF_DATA] s d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 x x xxx

SCA3000-E01,-E02

Ring buffer in 8-bit

mode [BUF_DATA] s d6 d5 d4 d3 d2 d1 d0 x x x x x xxx

s = sign bit

x = not used bit

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Table 8. Bit level description for acceleration registers of SCA3000-E04.

Byte MSB byte LSB byte

Bit number

Acceleration [mg] B7

Sign B6

4096 B5

2048 B4

1024 B3

512 B2

256 B1

128 B0

64 B7

32 B6

16 B5

8 B4

4 B3

2 B2:B0

xxx

SCA3000-E04

[X_LSB…Z_MSB] s d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 xxx

SCA3000-E04

Ring buffer in 11-bit

mode [BUF_DATA] s d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 x x xxx

SCA3000-E04

Ring buffer in 8-bit

mode [BUF_DATA] s d6 d5 d4 d3 d2 d1 d0 x x x x x xxx

s = sign bit

x = not used bit

Table 9. Bit level description for acceleration registers of SCA3000-E05.

Byte MSB byte LSB byte

Bit number

Acceleration [mg] B7

Sign B6

12800 B5

6400 B4

3200 B3

1600 B2

800 B1

400 B0

200 B7

100 B6

50 B5

25 B4

12.5 B3

6.25 B2:B0

xxx

SCA3000-E05

[X_LSB…Z_MSB] s d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 xxx

SCA3000-E05

Ring buffer in 11-bit

mode [BUF_DATA] s d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 x x xxx

SCA3000-E05

Ring buffer in 8-bit

mode [BUF_DATA] s d6 d5 d4 d3 d2 d1 d0 x x x x x xxx

s = sign bit

x = not used bit

Address: 12h

Register name: TEMP_LSB, temperature LSB frame

Bits Mode Initial

Value Name Description

7:0 R 00h TEMP Temperature LSB frame

Address: 13h

Register name: TEMP_MSB, temperature MSB frame

Bits Mode Initial

Value Name Description

7:0 R 00h TEMP Temperature MSB frame

The bit level description for temperature data from TEMP_MSB and TEMP_LSB registers is

presented in Table 10. Temperature data is presented in unsigned format. The LSB bit (bit B5 or t0

in Table 10) weight is ~0.56°C. See section 2.6 for more detailed information of converting the data

to temperature in [°C].

Table 10. Bit level description for temperature registers [TEMP_MSB … TEMP_LSB].

Register TEMP_MSB TEMP_LSB

Bit number B7:B6 B5 B4 B3 B2 B1 B0 B7 B6 B5 B4:B0

Bit in temperature

register xx t8 t7 t6 t5 t4 t3 t2 t1 t0 xxxxx

x = not used bit

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Address: 15h

Register name: BUF_COUNT, output ring buffer status

Bits Mode Initial

Value Name Description

7:0 R 00h COUNT

Count of available data samples in output ring buffer,

for more information see section 2.5.2.

Address: 16h

Register name: INT_STATUS, interrupt status register (all interrupts that are available in current

operation mode)

Bits Mode Initial

Value Name Description

7 R 0 BUF_FULL Output ring buffer is ¾ full

1 – Ring buffer is ¾ full

0 – Ring buffer is not full

6 R 0 BUF_HALF Output ring buffer is ½ full

1 – Ring buffer is ½ full

0 – Ring buffer is not full

5:4 Reserved

3 R 0 FFD Free-fall detection

1 – Free-fall detected (0 g accele ration)

0 – Free-fall not detected

2:0 R 000 MD Motion detector triggered channel indication

1xx – Trigger on Y-axis

x1x – Trigger on X-axis

xx1 – Trigger on Z-axis

3.4 Configuration Registers

SCA3000 configuration register (marked with 'Conf' in Table 5) contents and bit definitions are

described in this section. Configuration registers are used to configure SCA3000 operation and the

operation parameters.

Address: 00h

Register name: REVID, ASIC revision ID number tied in metal

Bits Mode Initial

Value Name Description

7:4 R 2h REVMAJ Major revision number

3:0 R 1h REVMIN Minor revision number

Address: 02h

Register name: STATUS, status register

Bits Mode Initial

Value Name Description

7:6 Reserved

5 R 0 LOCK Status of lock register

0 – Lock is closed

1 – Lock is open

4:2 Reserved

1 R 0 CSME EEPROM checksum error

1 – EEPROM checksum error

0 – No error

0 R 0 SPI_FRAME SPI frame error. Bit is reset, when next correct SPI

frame is received (only for products with SPI bus).

1 – SPI frame error

0 – No error

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Address: 14h

Register name: MODE, operation mode selection

Bits Mode Initial

Value Name Description

7 RW 0 BUF_EN Output ring buffer

1 – Enabled

0 – Disabled (Buffer in power down)

6 RW 0 BUF_8BIT Output ring buffer data length

1 – Ring buffer is read in single 8 bit frame per

stored axis (8 bit mode)

0 – Ring buffer is read in two 8 bit frames pe r

stored axis (11 bit mode). Unused bits are

set to 0.

5 Reserved

4 RW 0 FFD_EN Free-fall detection

1 – Enabled

0 – Disabled (detection in power down)

3 Reserved

2:0 RW 000 MODE_BITS Selects SCA3000 series operation mode

000 – Normal measuremen t mode

010 – Optional measurement mode 1 (see Table 2)

001 – Optional measurement mode 2 (see Table 2)

011 – MD, Motion Detector

Other combinations are reserved

Address: 17h

Register name: I2C_RD_SEL, register a ddress for I 2C read operation

Bits Mode Initial

Value Name Description

7:0 W 00h ADDR Addres s of register to be read via I2C. Register is

used only for I2C read access.

Address: 18h

Register name: CTRL_SEL, Control register sele ctor, UNLOCK REQUIRED

Bits Mode Initial

Value Name Description

7:5 RW 000 Reserved

4:0 RW 00000 SELECT Indirect control registers,

select register address for read / write access:

00001 – I2C_DISABLE

00010 – MD_CTRL (Motion Detector control)

00011 – MD_Y_TH (Motion Detector Y-

threshold)

00100 – MD_X_TH (Motion Detector X-

threshold)

00101 – MD_Z_TH (Motion Detector Z-

threshold)

01011 – OUT_CTRL (Output control)

Other combinations are reserved

CTRL_SEL register works as an address pointer for registers listed below. When this register is

written the content of selected register is available for reading/writing from/to register CTRL_DATA.

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Address value: 00010

Register name: MD_CTRL, Motion Detector control (Indirect access via CT RL_SEL)

Bits Initial

Value Name Description Note

7:6 Reserved

5 0 REQ_Z 1 – Require trigger on Z-channel

0 – Not required

4 0 REQ_X 1 – Require trigger on X-channel

0 – Not required

3 0 REQ_Y 1 – Require trigger on Y-channel

0 – Not required

Bits 5:3 can be

used to build logical

AND operation

between channels.

Example:

X and Y = Require

X and Y, ignore Z

→ 00 011 011

2 1 EN_Z 1 – Enable trigger on Z-channel

0 – Not required

1 1 EN_X 1 – Enable trigger on X-channel

0 – Not required

0 1 EN_Y 1 – Enable trigger on Y-channel

0 – Not required

Bits 2:0 can be

used to build logical

OR operation

between channels.

Example:

X or Y = Disable Z

→ 00 000 011

Address value: 00011

Register name: MD_Y_TH, Motion Detector Y-threshold (Indirect access via CTRL_SEL)

Bits Initial

Value Name Description

7:0 10h or 08h Y_TH Threshold for Y-acceleration change when MD

is used.

Address value: 00100

Register name: MD_X_TH, Motion Detector X-threshold (Indirect access via CTRL_SEL)

Bits Initial

Value Name Description

7:0 10h or 08h X_TH Threshold for X-acceleration change when MD

is used.

Address value: 00101

Register name: MD_Z_TH, Motion Detector Z-threshold (Indirect access via CTRL_SEL)

Bits Initial

Value Name Description

7:0 10h or 08h Z_TH Threshold for Z-acceleration cha nge when MD is

used.

Initial values for registers MD_X_TH, MD_Y_TH and MD_Z_TH vary with SCA3000 product types.

Initial value is:

• 10h for SCA3000-D01, SCA3000-D02, SCA3000-E01 and SCA30 00-E02

• 08h for SCA3000-E04 and SCA3000-E05

The bit level descriptions for registers MD_X_TH, MD_Y_TH and MD_Z_TH are presented in,

Table 11 ...Table 14 below. The threshold levels are in unsigned format and they are absolute

values for the acceleration that triggers the motion detector interrupt. Values presented below are

typical threshold values and they are not factory calibrated.

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Table 11. Bit level description for motion detector typical threshold levels (SCA3000-D01 and

SCA3000-D02).

Typical bit weights

Bit number B7 B6 B5 B4 B3 B2 B1 B0

SCA3000-D01, -D02

Acceleration [mg]

MD_X_TH, MD_TH_Z x x 1300 650 350 200 100 50

SCA3000-D01, -D02

Acceleration [mg]

MD_Y_TH x 1750 850 450 250 150 100 50

x = not used bit

Table 12. Bit level description for motion detector typical threshold levels (SCA3000-E01 and

SCA3000-E02).

Typical bit weights

Bit number B7 B6 B5 B4 B3 B2 B1 B0

SCA3000-E01, -E02

Acceleration [mg]

MD_X_TH, MD_TH_Z x x 2050 1050 550 300 150 100

SCA3000-E01, -E02

Acceleration [mg]

MD_Y_TH x 2700 1350 700 350 200 100 50

x = not used bit

Table 13. Bit level description for motion detector typical threshold levels (SCA3000-E04).

Typical bit weights

Bit number B7 B6 B5 B4 B3 B2 B1 B0

SCA3000-E04

Acceleration [mg]

MD_X_TH, MD_TH_Z x x 4100 2100 1100 600 300 200

SCA3000-E04

Acceleration [mg]

MD_Y_TH x 5400 2700 1400 700 400 200 100

x = not used bit

Table 14. Bit level description for motion detector typical threshold levels (SCA3000-E05).

Typical bit weights

Bit number B7 B6 B5 B4 B3 B2 B1 B0

SCA3000-E05

Acceleration [mg]

MD_X_TH, MD_TH_Z x x 11900 6100 3200 1700 900 600

SCA3000-E05

Acceleration [mg]

MD_Y_TH x 15600 7800 4100 2000 1200 600 300

x = not used bit

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Address value: 01011

Register name: OUT_CTRL, Output configuration (Indirect access via CTRL_SEL)

Bits Initial

Value Name Description

7:5 Reserved

4 1 BUF_X_EN Store X-axis acceleration data to ring buffer

1 – enabled

0 – disabled

3 1 BUF_Y_EN Store Y-axis acceleration data to ring buffer

1 – enabled

0 – disabled

2 1 BUF_Z_EN Store Z-axi s accele ration data to ring buffer

1 – enabled

0 – disabled

1:0 00 BUF_RATE Additional data rate reduction after calibration

before data is loaded to ring buffer (no effect on

output registers data rate, see section 2.5.1)

11 – No rate reduction

10 – divide rate by 4

01 – divide rate by 2

00 – No rate reduction

Address: 1Eh

Register name: UNLOCK, Unlock register lock

Bits Mode Initial

Value Name Description

7:0 RW 00h KEY Lock can be opened by writing the following

sequence into this register:

00h, 50h, A0h Writing any other sequence cl oses the

lock. Lock state can be read from STATUS regi ster.

Address: 21h

Register name: INT_MASK, HW interrupt mask register configures the operation of the INT pin.

Bits Mode Initial

Value Name Description

7 RW 0 BUF_F_EN Interrupt when output ring buffer is ¾ full

1 – Enabled

0 – Disabled

6 RW 1 BUF_H_EN Interrupt when output ring buffer is ½ full

1 – Enabled

0 – Disabled

5:2 Reserved

1 RW 0 INT_ALL Mask all interrupts (only effects on the INT-pin)

1 – Mask all interrupts (including free fall

detection and motion detector)

0 – Mask interrupts according to configured mode

0 RW 1 INT_ACT INT-pin signal activity

1 – INT active high (INT-pi n high)

0 – INT active low (INT-pi n low)

Address: 22h

Register name: CTRL_DATA, Control register data, UNLOCK REQUIRED

Bits Mode Initial

Value Name Description

7:0 RW 00h DATA Data bits [7:0] of selected 8-bit control register. Write

this register to actually perform the write operation to

selected location. See register CTRL_SEL for

information on register contents.

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4 Serial Interfaces

Communication between the SCA3000 sensor and master controller is based on serial data

transfer and a dedicated interrupt line (INT-pin). Two different serial interfaces are available for the

SCA3000 sensor: SPI and I2C (Phillips specification V2.1). However, only one per product is

enabled by pre-programming in the factory. The SCA3000 acts as a slave on both the SPI and I2C

bus.

4.1 SPI Interface

SPI bus is a full duplex synchronous 4-wire serial interface. It consists of one master device and

one or more slave devices. The master is defined as a micro controller providing the SPI clock, and

the slave as any integrated circuit receiving the SPI clock from the master. The SCA3000 sensor

always operates as a slave device in master-slave operation mode. A typical SPI connection is

presented in Figure 5.

DATA OUT (MOSI)

DATA IN (MISO)

SER IA L CL OC K (SC K)

SS0

SS1

SS2

SS3

MASTER

MICROCONTROLLER

SI

SO

SCK

CS

SLAVE

SI

SO

SCK

CS

SI

SO

SCK

CS

SI

SO

SCK

CS

Figure 5. Typical SPI connection.

The data transfer uses the following 4-wire interface:

MOSI master out slave in µC → SCA3000

MISO master in slave out SCA3000 → µC

SCK serial clock µC → SCA3000

CSB chip select (low activ e ) µC → SCA3000

4.1.1 SPI frame format

SCA3000 SPI frame format and transfer protocol is presented in Figure 6.

Figure 6. SPI frame format.

Each communication frame contains 16 bits. The first 8 bits in MOSI line contains info about the

operation (read/write) and the register address being accessed. The first 6 bits define the 6 bit

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address for the selected operation, which is defined by bit 7 (‘0’ = read ‘1’ = write), which is

followed by one zero bit. The later 8 bits in the MOSI line contain data for a write operation and are

‘don’t-care’ for a read operation. Bits from MOSI line are sampled in on the rising edge of SCK and

bits to MISO line are latched out on falling edge of SCK.

The first bits in the MISO line are the frame error bit (SPI_FRAME, bit 2) of the previous SPI frame

and odd parity bit (PAR, bit 8). Parity is calculated from data which is currently sent. Bit 7 is always

‘1’. The later 8 bits contain data for a read operation. During the write operation, these data bits are

previous data bits of the addressed register.

For write commands, data is written into the addressed register on the rising edge of CSB. If the

command frame is invalid as described in the section data will not be written into the register

(please see "error conditioning" in se ction 4.1.2).

For read commands, data is latched into the internal SPI output register (shift register) on the 8th

rising edge of SCK. The output register is shifted out MSB first over MISO outpu t.

When the CSB is high state between data transfers, the MISO line is in the high-impedance state.

4.1.2 SPI bus error conditioning

While sending an SPI frame, if the CSB is raised to 1

- before sending 16 SCKs or

- the number of SCK pulses is not divisible by 8,

the frame error is activated and the frame is considered invalid. The status bit

STATUS.SPI_FRAME is set to indicate the frame error condition. During the next SPI, the frame

error bit is sent out as SPI_FRAME bit (see SPI_FRAME in MISO line in Figure 6).

STATUS.SPI_FRAME bit is reset, if correct frame is received.

When an invalid frame is received, the last command is simply ignored and the register contents

are left unchanged. If frame error happens while sending multiple samples in ring buffer mode, only

the last output value is considered invalid.

4.1.3 Examples of SPI communication

4.1.3.1 Example of register read

An example of 11 bit X-axis acceleration read command is presented in Figure 7. The master gives

the register address to be read via the MOSI line: '05' in hex format and '000101' in binary format,

register name is X_MSB (X-axis MSB frame). 7th bit is set to '0' to indicate the read operation.

The sensor replies to a requested operation by transferring the register content via MISO line. After

transferring the asked X_MSB register content, the master gives next register address to be read:

'04' in hex format and '000100' in binary format, register name is X_LSB (X-axis LSB frame). The

sensor replies to the reque sted op eration by transferring the register conte nt MSB first.

Figure 7. An example of SPI read communication.

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4.1.3.2 Example of decremented register read

Figure 8 presents a decremented read operation where the content of four output registers is read

by one SPI frame. After normal register addressing and one register content reading, the µC keeps

the CSB line low and continues supplying the SCK pulses. After every 8 SCK pulses, the output

data address is decremented by one and the previous acceleration output register's content is

shifted out without parity bits. The parity bit in Figure 4 is calculated and transferred only for the first

data frame. From the X_LSB register address, the SCA3000 jumps to Z_MSB. Decremented

reading is possible only for registers X_LSB ... Z_MSB.

Figure 8. An example of decremented read operation.

4.1.3.3 Example of ring buffe r read

An example of output ring buffer read by one SPI frame (ring buffer data length 8 bits) is presented

in Figure 9. The whole ring buffer read procedure is very similar to decremented read described

above. The output ring buffer is addressed (register name BUF_DATA). The SCA3000 sensor

continues shifting out the ring buffer content as long as µC continues supplying th e SCK pulses.

Figure 9. An example of output ring buffer read opera t ion.

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4.2 I2C Interface

I2C is a 2-wire serial interface. It consists of one master device and one or more slave devices. The

master is defined as a micro controller providing the serial clock (SCL), and the slave as any

integrated circuit receiving the SCL clock from the master. The SCA3000 sensor always operates

as a slave device in master-slave operation mode. When using an SPI interface, a hardware

addressing is used (slaves have dedicated CSB signals), the I2C interface uses a software based

addressing (slave devices have dedicat ed bit patterns as addresses).

The SCA3000 is compatible to the Philips I2C specification V2.1. Main used features of the I2C

interface are:

- 10-bit addressing, SCA3000 I2C device address is 0x1F1

- Supports standard mode and fast mode

- Start / Restart / Stop

- Slave transceiver mode

- Designed for low power consumption

In addition to the Philips specification, the SCA3000 I2C interface supports multi ple write and read

mode.

4.2.1 I2C frame format

4.2.1.1 I2C write mode

In I2C write mode, the first 8 bits after device address define the SCA3000 internal register address

to be written. If multiple data words are transferred by the master, the register address is

decreased automatically by one (see cases 1 and 2 in Figure 10).

4.2.1.2 I2C read mode

The read mode operates as described in Philips I2C specification. I2C read operation returns the

content of the register which address is defined in I2C_RD_SEL register. So when performing the

I2C read operation, the register address to be read has to be written into I2C_RD_SEL register

before actual read operation. Read operation starts from register address that has been written

earlier in I2C_RD_SEL register. Read data is acknowledged by I2C master. Automatic read

address change depends on the selected start address (see cases 3 and 4 in Figure 10).

- If address is some of registers between X_LSB Æ Z_MSB the register address is automatically

cycled as foll ows:

... ÆY_MSB Æ Y_LSB Æ X_MSB Æ X_LSB Æ Z_MSB Æ Z_LSB Æ Y_MSB Æ Y_LSB Æ ...

- If the start address is any other register, the read address is NOT automatically incremented or

decremented (the data transfer continues from the same address.) This enables the burst read

from output ring buffer (register BUF_DATA).

4.2.1.3 Decremented register read

Decremented reading is possible only for registers X_LSB ... Z_MSB. Refer to decremented read

with SPI interface section 4.1.3.2.

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4.2.2 Examples of I2C communication

Examples of I2C communication are presented below in Figure 10.

S 0 SA SA SA SA

device addr 1st byte

11110AA device addr 2nd byte

AAAAAAAA regi ster addr

8 bits, MSB first register da ta

8 bits, MSB first

CASE 1: I2C 8 bit write

S 0 SA SA SA SA

device addr 1st byte

11110AA device addr 2nd byte

AAAAAAAA regi ster addr

8 bits, MSB first reg ister data, addr + 0

8 bits , MSB first

CASE 2: I2C 16 bit write (any number of bytes can be written, length is determined by end condition generated by master)

SA

re gister data, addr - 1

8 bits

,

MS B fi r st

E

S 0 SA SA MA

device addr 1st byte

11110AA device addr 2nd byte

AAAAAAAA register da ta, addr

8 bits, MSB first

CASE 3: I2C 8 bit read, read address for SCA3000 series register should be written to I2C_RD_SEL register

CASE 4: I2C 16 bit read (any nu mber of bytes can be read, lengt h is determined by end condition generated by master).

Automatic register address changing depends on selected start address in I2C_RD_SEL (noted by addr and addr_x on the figure).

E

S = Start condition

RS = Repeated s tart co ndition

E = End condition

SA = Slave Acknowledgement

MA = Master Acknowledgement

AA = Device address, 10 bits

Read/write select bit

(0=write, 1=read)

RS device addr 1st byte

11110AA 1SA

S 0 SA SA MA

device addr 1st byte

11110AA device addr 2nd byte

AAAAAAAA register da ta, addr

8 bits, MSB first E

RS device addr 1st byte

11110AA 1SA MA

register data, addr_x

8 bits, MSB first

E

Figure 10. I2C frame format.

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5 Electrical Characteristics

All voltages are reference to ground. Cu rrents flowing into the circuit have positive values.

5.1 Absolute maximum ratings

The absolute maximum ratings of the SCA3000 are prese nted in Table 15 below.

Table 15. Absolute maximum ratings of the SCA3000

Parameter Value Unit

Supply voltage (Vdd) -0.3 to +3.6 V

Voltage at input / output pins -0.3 to (Vdd + 0.3) V

ESD (Human body model) ±2 kV

Storage temperature -40 ... +125 °C

Storage / operating temperature -40 ... +85 °C

Mechanical shock * > 10 000 g

Ultrasonic cleaning Not allowed

* 1 m drop on concrete may cause >>10000 g shock.

ULTRASONIC AGITATION NO T ALLOWED.

5.2 Power Supply

Please refer to the corre sponding product datasheet.

5.3 Digital I/O Specification

5.3.1 Digital I/O DC characteristics

Table 16. DC characteristics of digital I/O pins.

No. Parameter Conditions Symbol Min Typ Max Unit

Input: CSB, MOSI, Xreset,

SCK_SCL has no pull up / pull down

1 Pull up current:

CSB VIN = 0 V IPU 10 50

µA

2 Pull down current:

MOSI VIN = Dvio IPD 10 50 µA

3 Pull up current

Xreset VIN = 0 V IPU 3 10

µA

4 Input high voltage VIH 0.7*Dvio V

5 Input low voltage VIL 0.3*Dvio V

6 Hysteresis VHYST 0.1*Dvio V

Output terminal: MISO_SDA, INT

7 Output high voltage I > -4 mA VOH 0.8*Dvio Dvio V

8 Output low voltage I < 4 mA VOL 0 0.2*Dvio V

9 Tristate leakage 0 < VMISO < 2.7 V ILEAK -2 2

µA

5.3.2 Digital I/O level shifter

All the SCA3000 products have an internal level shifter that can be used to interface e.g. a micro

controller using lower supply than the SCA3000. The level shifter is "programmed" by providing the

supply voltage of the interfaced device to the DVIO-pin. Please refer to the corresponding product

data sheet for details.

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5.3.3 SPI AC characteristics

The AC characteristics of the SCA30 00 SPI interface are defined in Figure 11 and in Table 17.

CSB

SCK

MOSI

MISO

TLS1 TCH

THOL TSET

TVAL1 TVAL2 TLZ

TLS2 TLH

MSB in

MSB out

LSB in

LSB o ut

DATA out

DATA in

TCL

Figure 11. Timing diagram for SPI communication.

Table 17. AC characteristics of SPI communication.

Parameter Conditions Symbol Min Typ Max Unit

Terminal CSB, SCK

1 Time from CSB (10%)

to SCK (90%)1 T

LS1 T

per/2 ns

2 Time from SCK (10%)

to CSB (90%)1 TLS2 Tper/2 ns

Terminal SCK

3 SCK low time Load

capacitance at

MISO < 35 pF

TCL 0.80*

Tper/2 Tper/2 ns

4 SCK high time Load

capacitance at

MISO < 35 pF

TCH 0.80*

Tper/2 Tper/2 ns

5 SCK Frequency fsck =

1/Tper Product

specific MHz

Terminal MOSI, SCK

6 Time from changing

MOSI (10%, 90%) to

SCK (90%)1. Data

setup time

TSET Tper/4 ns

7 Time from SCK (90%)

to changing MOSI

(10%, 90%)1. Data

hold time

T

HOL T

per/4 ns

Terminal MISO, CSB

8 Time from CSB (10%)

to stable MISO (10%,

90%)

Load

capacitance at

MISO < 35 pF

TVAL1 Tper/4 ns

9 Time from CSB (90%)

to high impedance

state of MISO1.

Load

capacitance at

MISO < 35 pF

TLZ T

per/4 ns

Terminal MISO, SCK

10 Time from SCK (10%)

to stable MISO (10%,

90%)1.

Load

capacitance at

MISO < 35 pF

TVAL2 1.3· Tper/4 ns

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Terminal MOSI, CSB

11 Time between SPI

cycles, CSB at high

level (90%)

T

LH 4 · Tper ns

Tper is SCK period

5.3.4 I2C AC characteristics

Please, see Phillips Semiconductors, The I2C bus specification, Version 2.1, January 2000, pp. 31-

33.

6 Package Characteristics

6.1 Dimensions

The package dimensions are presented in Figure 12 below (dimensions in millimeters [mm] with

±50 µm tolerance).

Figure 12. SCA3000 package dimensions.

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7 Application information

7.1 Pin Description

SCA3000 pin numbers are presented in Figure 14 below and pin descriptions in Table 18.

Figure 13. SCA3000 sensing directions . Figure 14. SCA3000 pin numbers.

Table 18. SCA3000 pin descriptions.

Pin # Name SCA3000-D01, SCA3000-E01,

SCA3000-E04

SCA3000-D02, SCA3000-E02

1 NC Not connected Not connected

2 XRESET External reset, active low External reset, active low

3 INT Interrupt output Interrupt output

4 CLK Connect to ground Connect to ground

5 DVSS Digital ground Digital ground

6 DVDD Digital supply Digital supply

7 DVIO Digital I/O supply Digital I/O supply

8 CSB Chip select Not connected

9 NC Not connected Not connected

10 NC Not connected Not connecte d

11 SCK_SCL SPI serial clock (SCK) I2C serial clock (SCL)

12 MISO_SDA SPI data out (MISO) I2C data in / out (SDA)

13 MOSI SPI data in (MOSI) Not connected

14 AVDD Analog suppl y Analog supply

15 AVSS Analog ground Analog ground

16 AVSS Analog ground Analog grou nd

17 ATSTIO Not connected Not connected

18 NC Not connected Not connecte d

7.2 Recommended circuit diagram

1. Connect 100 nF SMD capacitor between each supply voltage and g roun d level.

2. Connect 1 µF capacitor between each supply voltage and ground level.

3. Use one regulator for analog and digital sup ply (AVDD and DVDD).

4. Use separate regulator for digital IO supply (DVIO).

5. Xreset is needed always in start up: whe n Xreset is low, raise powe r supplies inside

specification, then set Xreset high.

6. INT-pin is used with output buffer as well as in Free Fall and Motion Detection mode.

7. Serial interface (SPI or I2C) logical '1' level is determined by DVIO supply voltage level.

Recommended circuit diagram fo r the SCA3000 with SPI interface is presented in Figure 15 below.

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Recommended circuit diagram for the SCA3000 with I2C interface is presented in Figure 16 below.

Figure 15. Recommended circuit diagram for the SCA3000 with SPI interface.

Figure 16. Recommended circuit diagram for the SCA3000 with I2C interface.

7.3 Recommended PWB layout

General PWB layout recom m endations for SCA3000 products (refer to Figure 15, Figure 16 and

Figure 17):

1. Locate 100 nF SMD capacitors right next to the SCA3000 package.

2. 1 µF capacitors can be located near the node where AVDD and DVDD are routed on separate

ways.

3. Use separate ground planes for AGND and DGND. Connect separate ground planes together

on PWB.

4. Use double sided PWB, connect the bottom side plane to DGND.

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Recommended PWB pad layout for SCA3000 is presented in Figure 17 below (dimensions in

millimeters, [mm]).

Recommended PWB layout for the SCA3000 with SPI interface is presented in Figure 18 below

(circuit diagram presented in Figure 15 above).

Figure 17. Recommended PWB pad layout for SCA3000.

Figure 18. Recommended PWB layout for SCA3000 with SPI interface (not actual size, for

reference only).

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Recommended PWB layout for SCA30 00 with I2C in terface is presented in Figure 19 below (ci rcuit

diagram presented in Figure 16 above).

Figure 19. Recommended PWB layout for SCA3000 with I2C interface (not actual size,

for reference only).

7.4 Assembly instructions

The Moisture Sensitivity Level (MSL) of the SCA3000 component is 3 according to the IPC/JEDEC

J-STD-020C. Please refer to the document "TN54 SCA3000 Assembly Instructions" for more

detailed information of SCA3000 assembly.

7.5 Tape and reel specifications

Please refer to the document "TN54 SCA3000 Assembly Instructions" for tape and reel

specifications.

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8 Data sheet references

8.1 Offset

SCA3000's offset will be calibrated in X = 0 g, Y = 0 g, and Z = +1 g (Z measuring axis is parallel to

earth’s gravitation) position, see Figure 20.

Z-axis in +1 g

position

Y

Earth’s

gravitation

X

Pin #1

Figure 20. SCA3000 offset (0 g) position.

8.1.1 Offset calibration error

Offset calibration error is the difference between the sensor's actual output reading and the nominal

output reading in calibration conditions. Error is calculated by

Equation 2

1000⋅

−

=−

−Sens OutputOutput

Offset axisX

raxisCalibEX ,

where OutputX-axisCalibEr is sensor’s X-axis calibration error in [mg], OutputX-axis is sensor’s X-axis

output reading [counts], Output is sensor’s nominal output in 0 g position and Sens sensor’s nominal

sensitivity [counts/g].

8.1.2 Offset temperature error

Offset temperature error is the difference between the sensor's output reading in different

temperatures and the sensor’s calibrated offset value at room temperature. Error is calculated by

Equation 3

1000

@@

@⋅

−

=−−

−Sens

OutputOutput

Offset RTaxisXTaxisX

TaxisTempErX ,

where OutputX-axisTempEr@T is sensor’s X-axis temperature error in [mg] in temperature T, OutputX-axis@T

is sensor’s X-axis output reading [counts] in temperature T, OutputX-axis@T X-axis output reading

[counts] at room temperature RT and Sens sensor’s nominal sensitivity [counts/g]. Sensor is in 0 g

position for every measurement point.

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8.2 Sensitivity

During sensitivity calibration, the sensor is placed in ±1 g positions having one of the sensor’s

measuring axis at a time parallel to the earth’s gravitation, see Figure 21.

Sensitivity is calculated by

Equation 4

g

OutputOutput

Sens gaxisYgaxisY

axisY 21@1@ −−+−

−

=,

where SensY-axis is sensor’s Y-axis sensitivity in [counts/g], OutputY-axis@+1g sensor’s Y-axis output

reading [counts] in +1 g position and OutputY-axis@-1g is sens or’s Y- axis o utpu t re ading [c oun ts] in - 1 g

position.

Pin #1

X

Y-axis in +1 g

position

Z

X Z

Y-axis in -1 g

position

Earth’s

gravitation

Pin #1

Figure 21. SCA3000 positions for Y-axis sensitivity measurement.

8.2.1 Sensitivity calibration error

Sensitivity calibration error is the difference between sensor’s measured sensitivity and the nominal

sensitivity at room temperature conditions. Error is calculated by

Equation 5

%100⋅

−

=−

−Sens SensSens

Sens axisY

raxisCalibEY ,

where SensY-axisCalibEr is sensor’s Y-axis sensitivity calibration error in [%], SensY-axis sensor’s Y-axis

sensitivity [counts/g] at room temperature conditions and Sens is sensor’s nominal sensitivity

[counts/g].

8.2.2 Sensitivity temperature error

Sensitivity temperature error is the difference between sensor’s sensitivity at different temperatures

and the calibrated sensitivity. Error is calculated by

Equation 6

%100

@

@@

@⋅

−

=

−

−−

−

RTaxisY

RTaxisYTaxisY

TaxisTempErY Sens

SensSens

Sens ,

where SensY-axisTempEr@T is sensor’s Y-axis sensitivity temperature error in [%] in temperature T, SensY-

axis@T is sensor’s measured Y-axis sensitivity [counts/g] at temperature T and SensY-axis@RT is sensor’s

measured Y-axis sensitivity [counts/g] at room temperature RT.

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8.3 Linearity

The linearity error characterization method described below is applied for those SCA3000 series

components that have measuring rang e ±3g or below.

Accurate input acceleration needed in linearity characterization is generated using centrifugal force

in centrifuge, see Figure 22. The RPM of the centrifuge is sweeped so that wanted input

acceleration values are applied in pa rallel to the sensor’s measuring axis.

Linearity error is the deviation from the straight line through sensor’s sensitivity calibration points,

see Figure 23.

Linearity error is calculated by

Equation 7

%100

@@

@⋅

⋅

−

=−

−FSSens

OutputOutput

LinEr accaccaxisZ

accaxisZ ,

where LinErZ-axis@acc is sensor’s Z-axis linearity error [%FS] on input acceleration acc, OutputZ-axis@acc

is sensor’s measured Z-axis output [counts] on input acceleration acc, Output@acc is sensor’s

X

Y

Z

Centrifugal

acceleration

for Z-axis

Pin #1

Figure 22. Centrifugal acceleration applied for SCA3000 Z-axis.

Input acceleration [g] (centrifugal

acceleration in parallel to

SCA3000 measuring axis)

SCA3000 output at

positive sensitivity

calibration point

SCA3000 linearity

error in [g] at input

acceleration acc

+1

g

-1 g

Possible offset error is not

included into linearity error

SCA3000 output

readings

Sensor’s ideal

output

Acceleration reading

from SCA3000 [g]

acc

Figure 23. SCA3000’s linearity error at input acceleration acc.

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nominal output [counts] on input acceleration acc, Sens is sensor’s nominal sensitivity [counts/g] and

FS is sensor’s full scale measuring range [g] (for example for SCA3000-D01 ±2g → FS = 2 g).

Sensor’s ideal output Output@acc (in Equation 7) is calculated from the straight line through

sensitivity calibration points (the red straight line in Figure 23). Nominal output is calculated by

Equation 8

222 111111

@gggggg

acc

OutputOutput

g

OutputOutput

accoffset

g

OutputOutput

accOutput −+−+−+

+

−

⋅=+

−

⋅= ,

where Output@acc is sensor’s nominal output [counts] with input acceleration acc in [g], Output+1g is

sensor’s measured output [counts] at +1 g input acceleration and Output-1g is sensor’s measured

output at -1 g input acceleration. Possible offset term [counts] is included into nominal output,

because it is not included in to linearity error.

8.4 Noise

Output noise nX, nY and nZ in X,Y and Z directions is the measured standard deviation of the output

values when the sensor is in 0 g position at room temperature. Average noise/axis is calculated by

Equation 9

()

222

3

1ZYX nnnn ++= ,

where n is sensor’s noise [g] per axis, nX is sensor’s X-axis noise [g], nY is sensor’s Y-axis noise [g]

and nZ is sensor’s Z-axis noise [g].

SCA3000 demo-kit design can be used as a reference design for noise measurements, refer to

“SCA3000 DEMO KIT User Manual 8259300”.

8.5 Bandwidth

Signal bandwidth is measured in a shaker by sweeping the piston movement frequency with

constant amplitude (Figure 24).

Z

Earth’s

gravitation

Shaker

movement

in parallel

to Z-axis

Y

X

Pin #1

Figure 24. SCA3000 movement in Z-axis ban dwidth measurement.

8.6 Cross-axis sensitivity

Cross-axis sensitivity is sum of the alignment and the inherent sensitivity errors. Cross-axis

sensitivity of one axis is a geometric sum of the sensitivities in two perpendicular directions.

Cross-axis sensitivity [%] of X-axis is given by

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Equation 10

%,100

22

⋅

+

±=

X

XZXY

XS

SS

Cross

where SXY is X-axis sensitivity to Y-axis acceleration [Count/g], SXZ is X-axis sensitivity to Z-axis

acceleration [Count/g] and SX is sensitivity of X-axis [Count/g].

Cross-axis sensitivity [%] of Y-axis is given by

Equation 11

%,100

22

⋅

+

±=

Y

YZYX

YS

SS

Cross

where SYX is Y-axis sensitivity to X-axis acceleration [Count/g], SYZ is Y-axis sensitivity to Z-axis

acceleration [Count/g] and SY is sensitivity of Y-axis [Count/g].

Cross-axis sensitivity [%] of Z-axis is given by

Equation 12

%,100

22

⋅

+

±=

Z

ZYZX

ZS

SS

Cross

where SZX is Z-axis sensitivity to X-axis acceleration [Count/g], SZY is Z-axis sensitivity to Y-axis

acceleration [Count/g] and SZ is sensitivity of Z-axis [Count/g].

Cross-axis sensitivity of SCA3000 family is measured in centrifuge over specified measurement

range during qualification. Correct mounting position of component is important during the

measurement of cross-axis sensitivity.

8.7 Turn-on time

Turn-on time is the time when the last of one X, Y, Z axis output readings stabilizes into its final

value after XRESET is pulled high. The final value limits in turn-on time measurements is defined to

be ±1 % of the sensor’s full scale measuring range (for example for SCA3000-D01 ±2g →

FS = 2 g). Turn-on time definition for Z-axis is presented in Figure 25 below.

SCA3000 output

inside ±1% FS

limits

SCA3000

Z-axis output

Acceleration

Turn on time Time scale

XRESET rise up

→ SCA3000 starts

Figure 25. Turn-on time definition for one axis.

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9 Order Information

Order code Description Packing Quantity

SCA3000-D01-1 3-Axis accelerometer with SPI interface, +/-2g, 100 pcs T&R 100

SCA3000-D01-10 3-Axis accelerometer with SPI interface, +/-2g, 1000 pcs T&R 1000

SCA3000-D01-25 3-Axis accelerometer with SPI interface, +/-2g, 2500 pcs T&R 2500

SCA3000-D02-1 3-Axis accelerometer with I2C interface, +/-2g, 100 pcs T&R 100

SCA3000-D02-10 3-Axis accelerometer with I2C interface, +/-2g, 1000 pcs T&R 1000

SCA3000-D02-25 3-Axis accelerometer with I2C interface, +/-2g, 2500 pcs T&R 2500

SCA3000-E01-1 3-Axis accelerometer with SPI interface, +/-3g, 100 pcs T&R 100

SCA3000-E01-10 3-Axis accelerometer with SPI interface, +/-3g, 1000 pcs T&R 1000

SCA3000-E01-25 3-Axis accelerometer with SPI interface, +/-3g, 2500 pcs T&R 2500

SCA3000-E02-1 3-Axis accelerometer with I2C interface, +/-3g, 100 pcs T&R 100

SCA3000-E02-10 3-Axis accelerometer with I2C interface, +/-3g, 1000 pcs T&R 1000

SCA3000-E02-25 3-Axis accelerometer with I2C interface, +/-3g, 2500 pcs T&R 2500

SCA3000-E04-1 3-Axis accelerometer with SPI interface, +/-6g, 100 pcs T&R 100

SCA3000-E04-10 3-Axis accelerometer with SPI interface, +/-6g, 1000 pcs T&R 1000

SCA3000-E04-25 3-Axis accelerometer with SPI interface, +/-6g, 2500 pcs T&R 2500

SCA3000-E05-1 3-Axis accelerometer with SPI interface, +/-18g, 100 pcs T&R 100

SCA3000-E05-10 3-Axis accelerometer with SPI interface, +/-18g, 1000 pcs T&R 1000

SCA3000-E05-25 3-Axis accelerometer with SPI interface, +/-18g, 2500 pcs T&R 2500

SCA3000-D01 PWB PWB assy, 3-Axis accelerometer with SPI interface, +/-2g Bulk 1

SCA3000-D02 PWB PWB assy, 3-Axis accelerometer with I2C interface, +/-2g Bulk 1

SCA3000-E01 PWB PWB assy, 3-Axis accelerometer with SPI interface, +/-3g Bulk 1

SCA3000-E02 PWB PWB assy, 3-Axis accelerometer with I2C interface, +/-3g Bulk 1

SCA3000-E04 PWB PWB assy, 3-Axis accelerometer with SPI interface, +/-6g Bulk 1

SCA3000-E05 PWB PWB assy, 3-Axis accelerometer with SPI interface, +/-18g Bulk 1

SCA3000-D01DEMO SCA3000-D01 DEMOKIT Bulk 1

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10 Document Change Control

Version Date Change Description

0.01 09.09.2005 Initial draft.

.... ...

0.08 20.09.2005 Draft release for schematic and layout design.

0.09 23.09.2005 FF and MD description added.

0.10 12.10.2005

Introduction and functional descriptions edited,

measurement mode, ring buffer, temperature measurement, interrupt, oscillator, reset and register

descriptions added. Register and bit names changed to be more descriptive.

0.11 13.10.2005 Typo etc minor corrections.

0.12 14.10.2005 Draft release.

0.13 01.11.2005 Register initial values and examples added.

0.14 09.11.2005 Language corrections.

0.15 26.01.2006 New product versions updated.

Output and ring buffer bit level definitions changed. This definition is valid from samples v0.3

onwards. Register level changes in temperature output.

0.16 15.02.2006

Updated:

- absolute maximum ratings,

- temperature output equation,

- I2C device address,

specification references

0.17 14.03.2006 Updated:

- recommended circuit diagrams, sections “Packing” and “Handling and storage” added

0.18 27.03.2006 Layout change

A 27.04.2006 Updated:

- recommended circuit diagrams,

- sections “Packing” and “Handling and storage”

- section “Specification references” updated and renamed to “Data sheet references”

MD threshold levels

A.01 27.06.2006

Updated:

- document name changed to "SCA3000 Product Family Specification"

- section "6.1 Package dimensions" updated

sections "7.4 Solder paste and stencil parameters" and "7.5 Reflow" updated to "7.4 Assembly

instructions"

- section "9.1 Packing and handling" updated to "7.5 Tape and reel specifications"

Contact information

A.02 30.6.2006 Order information added

A.03 11.9.2006 SCA3000-E04 information added

A.04 27.03.2007 Added:

- SCA3000-E04 wide band measurement mode,

- Typos corrected

- New product types: SCA3000-E05 and SCA3000-L01

A.05 01.06.2007

Added:

- New product type: SCA3000-D03

- I2C communication added for SCA3000-L01

A.06 30.10.2007 Corrections: typos, axis orientation

A.07 02.02.2009

Corrected recommended PWB layouts. Removed references to D03 and L01.

SCA3000 Series

VTI Technologies Oy 43/ 43

www.vti.fi Doc.Nr. 8257300A.07 Rev.A.07

11 Contact Information

Finland

(head office)

VTI Technologies Oy

P.O. Box 27

Myllynkivenkuja 6

FI-01621 Vantaa

Finland

Tel. +358 9 879 181

Fax +358 9 8791 8791

E-mail: sales@vti.fi

Germany

VTI Technologies Oy

Branch Office Frankfurt

Rennbahnstrasse 72-74

D-60528 Frankfurt am Main,

Germany

Tel. +49 69 6786 880

Fax +49 69 6786 8829

E-mail: sales.de@vti.fi

USA

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

E-mail: sales@vtitechnologies.com

Japan

VTI Technologies Oy

Tokyo Office

Tokyo-to, Minato-ku 2-7-16

Bureau Toranomon 401

105-0001

Japan

Tel. +81 3 6277 6618

Fax +81 3 6277 6619

E-mail: sales.japan@vti.fi

China

VTI Technologies Shanghai Office

6th floor, Room 618

780 Cailun Lu

Pudong New Area

201203 Shanghai

P.R. China

Tel. +86 21 5132 0417

Fax +86 21 513 20 416

E-mail: sales.china@vti.fi

To find out your local sales

representative visit www.vti.fi