Product Family Specification SCA3000 Series 3-axis accelerometer

Product Family Specification SCA3000 Series 3-axis accelerometer
Doc.Nr. 8257300A.07
Product Family Specification
SCA3000 Series
3-axis accelerometer
SCA3000 Series
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
1.2.5.2
1.2.6
1.2.7
1.2.8
1.2.9
Measurement................................................................................................................................6
Motion Detection..........................................................................................................................6
Free-Fall Detection ..............................................................................................................6
Interrupt................................................................................................................................7
Temperature output ............................................................................................................7
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
2.2.1.2
2.2.1.3
2.2.2
Bypass measurement mode.......................................................................................................8
Narrow band measurement mode..............................................................................................8
Wide band measurement mode .................................................................................................8
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
2.5.3
Overflow condition ....................................................................................................................12
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
4.1.3.2
4.1.3.3
Example of register read...........................................................................................................25
Example of decremented register read ...................................................................................26
Example of ring buffer read ......................................................................................................26
4.2 I2C Interface ..............................................................................................................................27
4.2.1 I2C frame format.................................................................................................................27
4.2.1.1
4.2.1.2
4.2.1.3
4.2.2
I2C write mode ............................................................................................................................27
I2C read mode.............................................................................................................................27
Decremented register read .......................................................................................................27
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 Interconnection Device package (MID).
A block diagram of the SCA3000 product family is presented in Figure 1 below.
C/V
Oscillator
&
clock
Reference
Analog
calibration
&
ADC
DEMUX
1:3
NonVolatile
Memory
Low-pass
Filter
Decimation
Low-pass
Filter
Decimation
Low-pass
Filter
Decimation
Temperature
sensor
Motion
detector
SCK/SCL
Coordinate
Mapping
and
Calibration
SPI
&
I2C
i/f
MISO/SDA
MOSI
CSB
Free fall
detector
Ring
Buffer
Control
&
INT
INT
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 available in the corresponding data sheet.
1.2
1.2.1
Functional Description
Sensing element
The sensing element is manufactured using the proprietary bulk 3D-MEMS process, which enables
robust, stable and low noise & power capacitive 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 orthogonal 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 nonvolatile 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.
1.2.5
1.2.5.1
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
Motion
detection
Free fall
detection
User enabled,
64 sampl./axis
User enabled,
64 sampl./axis
User enabled,
64 sampl./axis
User enabled,
64 sampl./axis
User enabled
User enabled
User enabled
User enabled
User enabled
User enabled
User enabled
User enabled
Interface
SPI max 1.6 MHz (-D01) /
2
I C fast mode
(-D02)
SPI max 325 kHz
2
I C std mode
SPI max 325 kHz
SPI max 325 kHz
Temperatu
re output
Yes
No
No
No
Clock
Internal
Internal
Internal
Internal
(-E01) /
(-E02)
Operation modes
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 corresponding status register.
Normal acceleration information is not available 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 corresponding 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 nonvolatile 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
2.2.1
Measurement Mode
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
Default after power-on
or reset
Measurement
mode
Bypass
measurement
mode
SCA3000-E01
SCA3000-E02
Measurement
mode
Narrow band
measurement
mode
Not available
Not available
Optional measurement
mode 1
Optional measurement
mode 2
2.2.1.1
SCA3000-E04
SCA3000-E05
Measurement
mode
Narrow band
measurement
mode
Wide band
measurement
mode
Measurement
mode
Narrow band
measurement
mode
Wide band
measurement
mode
Bypass measurement 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 measurement 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_LSB … Z_MSB and BUF_DATA).
Table 3. Overflow bit patterns in acceleration data registers (X_LSB … Z_MSB and BUF_DATA).
Byte
MSB byte
Bit number
B7 B6 B5 B4
Acceleration data bit Sign d11 d10 d9
Data overflow on
0
1
1
x
positive acceleration
Data overflow on
1
0
0
x
negative
acceleration
LSB byte
B0 B7 B6
d5 d4 d3
B3
d8
B2
d7
B1
d6
x
x
x
x
x
x
x
x
x
x
B5
d2
B4
d1
B3 B2:B0
d0
x
x
x
x
xxx
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 measuring range.
SCA3000-D01
SCA3000-D02
First positive
acceleration value
out of range
Maximum positive
acceleration value
in range
Minimum negative
acceleration value
in range
First negative
acceleration value
out of range
2.3
2.3.1
[mg]
dec
bin
[mg]
dec
bin
[mg]
dec
bin
[mg]
dec
bin
SCA3000-E04
SCA3000-E05
3072
SCA3000-E01
SCA3000-E02
3072
3072
3072
0110 0000 0000 0xxx
0110 0000 0000 0xxx
0110 0000 0000 0xxx
0110 0000 0000 0xxx
2303.25 mg
3071
3071 mg
3071
6142 mg
3071
19193.75 mg
3071
0101 1111 1111 1xxx
0101 1111 1111 1xxx
0101 1111 1111 1xxx
0101 1111 1111 1xxx
-2304 mg
-3072
-3072 mg
-3072
-6144 mg
-3072
-19200 mg
-3072
1010 0000 0000 0xxx
1010 0000 0000 0xxx
1010 0000 0000 0xxx
1010 0000 0000 0xxx
-3073
-3073
-3073
-3073
1001 1111 1111 1xxx
1001 1111 1111 1xxx
1001 1111 1111 1xxx
1001 1111 1111 1xxx
Motion Detection Mode
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 function.
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 reference only
5
Attenuation [dB]
0
-5
Lower limit
Upper limit
-10
-15
-20
0.01
0.1
1 Freq [Hz] 10
100
1000
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 threshold 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).
Acceleration
X, Y or Z
Acceleration exceeds
the threshold level
due to motion
+TL
T1
T2
T3
T4
T5
T6
T7
T8
Time
T1
T2
T3
T4
T5
T6
T7
T8
Time
-TL
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 XOR Y-axis direction:
1. Write "00000011" (03h) into MODE register (enable motion detection mode,
MODE_BITS = '011')
2. Write "00000000" (00h) into UNLOCK register
Unlock sequence for register lock
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)
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
2.4.1
Free-Fall Detection
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.
Acceleration
X, Y and Z
+TL
T1
T2
T3
T4
T5
T6
T7
T8
Time
T6
T7
T8
Time
-TL
TFF
INT output
"1"
"0"
T1
T2
T3
T4
T5
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- and 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
Unlock sequence for register lock
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)
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_DATA 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 information.
2.6
2.6.1
Temperature measurement
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 accessed. 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
Temp[°C ] = 23°C +
Tempdec − 256 LSB
LSB
1 .8
°C
where Temp[°C] is temperature in Celsius and Tempdec is the temperature from TEMP_MSB and
TEMP_LSB registers in decimal format.
2.7
2.7.1
Interrupt function (INT-pin)
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 register 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 contents and bit definitions are described in more detail in the following
sections.
3.1
Register Description
The SCA3000 addressing space is presented in Table 5 below.
Table 5. List of registers.
Addr.
Name
Description
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah ... 0Eh
0Fh
10h ... 11h
12h
13h
14h
REVID
ASIC revision ID number
Reserved
Status register
Reserved
X-axis LSB frame
X-axis MSB frame
Y-axis LSB frame
Y-axis MSB frame
Z-axis LSB frame
Z-axis MSB frame
Reserved
Ring buffer output register
Reserved
Temperature LSB frame
Temperature MSB frame
Operating mode selection,
control and configuration for:
- mode selection
- output buffer
- free-fall detection
Count of unread data
samples in output buffer
Interrupt status register:
- output buffer is not full, ½
full or ¾ full
- free-fall detected / not
detected
- information of which axis
triggered motion
Register address for I2C read
operation
Register address pointer for
indirect control registers
X_LSB
X_MSB
Y_LSB
Y_MSB
Z_LSB
Z_MSB
BUF_DATA
TEMP_LSB
TEMP_MSB
MODE
15h
BUF_COUNT
16h
INT_STATUS
17h
I2C_RD_SEL
18h
CTRL_SEL
19h
...
1Dh
1Eh
1Fh ... 20h
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STATUS
Mode
(R, W, RW, IA)
R
Reg.
type
Conf
R
Conf
-
R
R
R
R
R
R
Output
Output
Output
Output
Output
Output
R
Output
R
R
RW
Output
Output
Conf
R
Output
R
Output
-
RW
Conf
RW
Conf
Reserved
UNLOCK
Unlock register
Reserved
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x
RW
Conf
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Addr.
Description
21h
INT_MASK
22h
CTRL_DATA
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)
Data to/from register which
address is in CTRL_SEL
(18h) register
Reserved
23h ... 3Fh
RW, NV
Reg.
type
Conf
RW, NV, IA
Conf
Mode
Name
(R, W, RW, IA)
Locked
x
-
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-volatile memory for calibration and configuration data. Memory
content will be programmed during production and is not user configurable. Initial configuration
values can be found in the following section 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
Initial
Bits
Mode
Name
Value
7:0
R
00h
DATA
Description
X-axis LSB frame
Address: 05h
Register name: X_MSB, X-axis MSB frame
Initial
Bits
Mode
Name
Description
Value
7:0
R
00h
DATA
X-axis MSB frame
Address: 06h
Register name: Y_LSB, Y-axis LSB frame
Initial
Bits
Mode
Name
Value
7:0
R
00h
DATA
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Y-axis LSB frame
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Address: 07h
Register name: Y_MSB, Y-axis MSB frame
Initial
Bits
Mode
Name
Description
Value
7:0
R
00h
DATA
Y-axis MSB frame
Address: 08h
Register name: Z_LSB, Z-axis LSB frame
Initial
Bits
Mode
Name
Value
7:0
R
00h
DATA
Description
Z-axis LSB frame
Address: 09h
Register name: Z_MSB, Z-axis MSB frame
Initial
Bits
Mode
Name
Description
Value
7:0
R
00h
DATA
Z-axis MSB frame
Address: 0Fh
Register name: BUF_DATA, ring buffer output register
Initial
Bits
Mode
Name
Description
Value
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
Bit number
B7 B6 B5 B4 B3
Acceleration [mg]
Sign 1536 768 384 192
SCA3000-D01,-D02
s d11 d10 d9 d8
[X_LSB…Z_MSB]
SCA3000-D01,-D02
Ring buffer in 11-bit s
d9 d8 d7 d6
mode [BUF_DATA]
SCA3000-D01,-D02
Ring buffer in 8-bit
s
d6 d5 d4 d3
mode [BUF_DATA]
B2
B1
LSB byte
B0 B7 B6
B5
B4
B3 B2:B0
96
48
24
12
6
3
1.5
0.75
xxx
d7
d6
d5
d4
d3
d2
d1
d0
xxx
d5
d4
d3
d2
d1
d0
x
x
xxx
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
Bit number
B7 B6 B5 B4 B3 B2
Acceleration [mg]
Sign 2048 1024 512 256 128
SCA3000-E01,-E02
s d11 d10 d9 d8 d7
[X_LSB…Z_MSB]
SCA3000-E01,-E02
d9 d8 d7 d6 d5
Ring buffer in 11-bit s
mode [BUF_DATA]
SCA3000-E01,-E02
s
d6 d5 d4 d3 d2
Ring buffer in 8-bit
mode [BUF_DATA]
B1
LSB byte
B0 B7 B6
B5
B4
64
32
16
8
4
2
d6
d5
d4
d3
d2
d1
d0
xxx
d4
d3
d2
d1
d0
x
x
xxx
d1
d0
x
x
x
x
x
xxx
B3 B2:B0
1
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
Bit number
B7 B6 B5 B4
Acceleration [mg]
Sign 4096 2048 1024
SCA3000-E04
s d11 d10 d9
[X_LSB…Z_MSB]
SCA3000-E04
Ring buffer in 11-bit s
d9 d8 d7
mode [BUF_DATA]
SCA3000-E04
Ring buffer in 8-bit
s
d6 d5 d4
mode [BUF_DATA]
B3
B2
B1
LSB byte
B0 B7 B6
B5
B4
512
256
128
64
32
16
8
4
d8
d7
d6
d5
d4
d3
d2
d1
d0
xxx
d6
d5
d4
d3
d2
d1
d0
x
x
xxx
d3
d2
d1
d0
x
x
x
x
x
xxx
B3 B2:B0
2
xxx
s = sign bit
x = not used bit
Table 9. Bit level description for acceleration registers of SCA3000-E05.
Byte
MSB byte
Bit number
B7 B6 B5 B4
Acceleration [mg]
Sign 12800 6400 3200
SCA3000-E05
s d11 d10 d9
[X_LSB…Z_MSB]
SCA3000-E05
d9 d8 d7
Ring buffer in 11-bit s
mode [BUF_DATA]
SCA3000-E05
s
d6 d5 d4
Ring buffer in 8-bit
mode [BUF_DATA]
B3
LSB byte
B7 B6
B3 B2:B0
xxx
B2
B1
B0
B5
B4
1600 800
400
200
100
50
25
12.5 6.25
d8
d7
d6
d5
d4
d3
d2
d1
d0
xxx
d6
d5
d4
d3
d2
d1
d0
x
x
xxx
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
Initial
Bits
Mode
Name
Description
Value
7:0
R
00h
TEMP
Temperature LSB frame
Address: 13h
Register name: TEMP_MSB, temperature MSB frame
Initial
Bits
Mode
Name
Description
Value
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
Bit number
Bit in temperature
register
TEMP_MSB
B7:B6 B5
xx
t8
B4
B3
B2
B1
B0
t7
t6
t5
t4
t3
TEMP_LSB
B7
B6
t2
t1
B5
B4:B0
t0
xxxxx
x = not used bit
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Address: 15h
Register name: BUF_COUNT, output ring buffer status
Initial
Bits
Mode
Name
Description
Value
Count of available data samples in output ring buffer,
7:0
R
00h
COUNT
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)
Initial
Bits
Mode
Name
Description
Value
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 acceleration)
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
Initial
Bits
Mode
Name
Description
Value
7:4
R
2h
REVMAJ
Major revision number
3:0
R
1h
REVMIN
Minor revision number
Address: 02h
Register name: STATUS, status register
Initial
Bits
Mode
Name
Value
7:6
5
R
0
LOCK
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1
R
0
0
R
0
Description
Reserved
Status of lock register
0 – Lock is closed
1 – Lock is open
Reserved
CSME
EEPROM checksum error
1 – EEPROM checksum error
0 – No error
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
Initial
Bits
Mode
Name
Description
Value
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 per
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
MODE_BITS
2:0
RW
000
Selects SCA3000 series operation mode
000 – Normal measurement 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 address for I2C read operation
Initial
Bits
Mode
Name
Description
Value
7:0
W
00h
ADDR
Address of register to be read via I2C. Register is
used only for I2C read access.
Address: 18h
Register name: CTRL_SEL, Control register selector, UNLOCK REQUIRED
Initial
Bits
Mode
Name
Description
Value
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 Ythreshold)
00100 – MD_X_TH (Motion Detector Xthreshold)
00101 – MD_Z_TH (Motion Detector Zthreshold)
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 CTRL_SEL)
Initial
Bits
Name
Description
Note
Value
7:6
Reserved
5
0
REQ_Z
1 – Require trigger on Z-channel Bits 5:3 can be
0 – Not required
used to build logical
4
0
REQ_X
1 – Require trigger on X-channel AND operation
between channels.
0 – Not required
3
0
REQ_Y
1 – Require trigger on Y-channel Example:
0 – Not required
X and Y = Require
X and Y, ignore Z
→ 00 011 011
2
1
EN_Z
1 – Enable trigger on Z-channel
Bits 2:0 can be
0 – Not required
used to build logical
1
1
EN_X
1 – Enable trigger on X-channel
OR operation
0 – Not required
between channels.
0
1
EN_Y
1 – Enable trigger on Y-channel
Example:
0 – Not required
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)
Initial
Bits
Name
Description
Value
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)
Initial
Bits
Name
Description
Value
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)
Initial
Bits
Name
Description
Value
7:0
10h or 08h
Z_TH
Threshold for Z-acceleration change 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 SCA3000-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]
x
x
1300 650
350
200
100
50
MD_X_TH, MD_TH_Z
SCA3000-D01, -D02
Acceleration [mg]
x
1750 850
450
250
150
100
50
MD_Y_TH
x = not used bit
Table 12. Bit level description for motion detector typical threshold levels (SCA3000-E01 and
SCA3000-E02).
Bit number
SCA3000-E01, -E02
Acceleration [mg]
MD_X_TH, MD_TH_Z
SCA3000-E01, -E02
Acceleration [mg]
MD_Y_TH
Typical bit weights
B7
B6
B5
B4
B3
B2
B1
B0
x
x
2050
1050
550
300
150
100
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).
Bit number
SCA3000-E04
Acceleration [mg]
MD_X_TH, MD_TH_Z
SCA3000-E04
Acceleration [mg]
MD_Y_TH
Typical bit weights
B7
B6
B5
B4
B3
B2
B1
B0
x
x
4100
2100
1100
600
300
200
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).
Bit number
SCA3000-E05
Acceleration [mg]
MD_X_TH, MD_TH_Z
SCA3000-E05
Acceleration [mg]
MD_Y_TH
Typical bit weights
B7
B6
B5
x
x
x
B4
11900 6100
15600 7800
4100
B3
B2
B1
B0
3200
1700
900
600
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)
Initial
Bits
Name
Description
Value
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-axis acceleration 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
Initial
Bits
Mode
Name
Description
Value
7:0
RW
00h
KEY
Lock can be opened by writing the following
sequence into this register:
00h, 50h, A0h Writing any other sequence closes the
lock. Lock state can be read from STATUS register.
Address: 21h
Register name: INT_MASK, HW interrupt mask register configures the operation of the INT pin.
Initial
Bits
Mode
Name
Description
Value
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-pin high)
0 – INT active low (INT-pin low)
Address: 22h
Register name: CTRL_DATA, Control register data, UNLOCK REQUIRED
Initial
Bits
Mode
Name
Description
Value
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.
MASTER
MICROCONTROLLER
SLAVE
DATA OUT (MOSI)
SI
DATA IN (MISO)
SO
SERIAL CLOCK (SCK)
SCK
SS0
CS
SS1
SI
SS2
SO
SS3
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
MISO
SCK
CSB
4.1.1
master out slave in
master in slave out
serial clock
chip select (low active)
µC → SCA3000
SCA3000 → µC
µC → SCA3000
µC → SCA3000
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 section 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 output.
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
4.1.3.1
Examples of SPI communication
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 requested operation by transferring the register content 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 buffer 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 the SCK pulses.
Figure 9. An example of output ring buffer read operation.
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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 dedicated 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 multiple write and read
mode.
4.2.1
4.2.1.1
I2C frame format
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 follows:
... 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.
Read/write select bit
CASE 1: I2C 8 bit write
S
(0=write, 1=read)
device addr 2nd byte
device addr 1st byte
0 SA
AAAAAAAA
11110AA
SA
register addr
8 bits, MSB first
register data
SA 8 bits, MSB first
SA E
CASE 2: I2C 16 bit write (any number of bytes can be written, length is determined by end condition generated by master)
S
device addr 1st byte
0 SA
11110AA
device addr 2nd byte
AAAAAAAA
SA
register addr
8 bits, MSB first
SA
register data, addr + 0
8 bits, MSB first
SA
register data, addr - 1
8 bits, MSB first
SA E
CASE 3: I2C 8 bit read, read address for SCA3000 series register should be written to I2C_RD_SEL register
S
device addr 2nd byte
device addr 1st byte
0 SA AAAAAAAA
11110AA
SARS
device addr 1st byte
11110AA
1 SA
register data, addr
8 bits, MSB first
MA E
CASE 4: I2C 16 bit read (any number of bytes can be read, length 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).
device addr 2nd byte
device addr 1st byte
0 SA AAAAAAAA
11110AA
S = Start condition
RS = Repeated start condition
E = End condition
SA = Slave Acknowledgement
MA = Master Acknowledgement
AA = Device address, 10 bits
S
device addr 1st byte
SA RS 11110AA
register data, addr
1 SA 8 bits, MSB first
register data, addr_x
MA 8 bits, MSB first
MAE
Figure 10. I2C frame format.
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5
Electrical Characteristics
All voltages are reference to ground. Currents flowing into the circuit have positive values.
5.1
Absolute maximum ratings
The absolute maximum ratings of the SCA3000 are presented in Table 15 below.
Table 15. Absolute maximum ratings of the SCA3000
Parameter
Supply voltage (Vdd)
Voltage at input / output pins
ESD (Human body model)
Storage temperature
Storage / operating temperature
Mechanical shock *
Ultrasonic cleaning
Value
-0.3 to +3.6
-0.3 to (Vdd + 0.3)
±2
-40 ... +125
-40 ... +85
> 10 000
Unit
V
V
kV
°C
°C
g
Not allowed
* 1 m drop on concrete may cause >>10000 g shock.
ULTRASONIC AGITATION NOT ALLOWED.
5.2
Power Supply
Please refer to the corresponding product datasheet.
5.3
5.3.1
Digital I/O Specification
Digital I/O DC characteristics
Table 16. DC characteristics of digital I/O pins.
No. Parameter
Conditions
Input: CSB, MOSI, Xreset,
SCK_SCL has no pull up / pull down
Pull up current:
VIN = 0 V
1
CSB
Pull down current:
VIN = Dvio
2
MOSI
Pull up current
VIN = 0 V
3
Xreset
Input high voltage
4
Input low voltage
5
Hysteresis
6
Output terminal: MISO_SDA, INT
Output high voltage
I > -4 mA
7
Output low voltage
I < 4 mA
8
Tristate leakage
0 < VMISO < 2.7 V
9
5.3.2
Symbol
Min
IPU
Typ
Max
Unit
10
50
µA
IPD
10
50
µA
IPU
3
10
µA
VIH
VIL
VHYST
0.7*Dvio
0.3*Dvio
V
V
V
VOH
VOL
ILEAK
0.8*Dvio
0
-2
Dvio
0.2*Dvio
2
V
V
µA
0.1*Dvio
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 SCA3000 SPI interface are defined in Figure 11 and in Table 17.
TLS1
TCH
TCL
TLS2
TLH
CSB
SCK
THOL
MOSI
TVAL1
MISO
TSET
MSB in
DATA in
LSB in
TVAL2
MSB out
TLZ
DATA out
LSB out
Figure 11. Timing diagram for SPI communication.
Table 17. AC characteristics of SPI communication.
Parameter
Terminal CSB, SCK
Time from CSB (10%)
1
to SCK (90%)1
Time from SCK (10%)
2
to CSB (90%)1
Terminal SCK
3
SCK low time
4
SCK high time
5
SCK Frequency
Load
capacitance at
MISO < 35 pF
Load
capacitance at
MISO < 35 pF
Symbol
Min
TLS1
Tper/2
ns
TLS2
Tper/2
ns
TCL
0.80*
Tper/2
Tper/2
ns
TCH
0.80*
Tper/2
Tper/2
ns
Typ
Max
Product
specific
fsck =
1/Tper
Terminal MOSI, SCK
6
Time from changing
MOSI (10%, 90%) to
SCK (90%)1. Data
setup time
7
Time from SCK (90%)
to changing MOSI
(10%, 90%)1. Data
hold time
Terminal MISO, CSB
8
Time from CSB (10%)
to stable MISO (10%,
90%)
9
Time from CSB (90%)
to high impedance
state of MISO1.
Terminal MISO, SCK
10 Time from SCK (10%)
to stable MISO (10%,
90%)1.
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Conditions
Unit
MHz
TSET
Tper/4
ns
THOL
Tper/4
ns
Load
capacitance at
MISO < 35 pF
Load
capacitance at
MISO < 35 pF
TVAL1
Tper/4
ns
TLZ
Tper/4
ns
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%)
Tper is SCK period
5.3.4
TLH
4 · Tper
ns
I2C AC characteristics
Please, see Phillips Semiconductors, The I2C bus specification, Version 2.1, January 2000, pp. 3133.
6
6.1
Package Characteristics
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
7.1
Application information
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 #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
7.2
Name
SCA3000-D01, SCA3000-E01,
SCA3000-E04
SCA3000-D02, SCA3000-E02
NC
XRESET
INT
CLK
DVSS
DVDD
DVIO
CSB
NC
NC
SCK_SCL
MISO_SDA
MOSI
AVDD
AVSS
AVSS
ATSTIO
NC
Not connected
External reset, active low
Interrupt output
Connect to ground
Digital ground
Digital supply
Digital I/O supply
Chip select
Not connected
Not connected
SPI serial clock (SCK)
SPI data out (MISO)
SPI data in (MOSI)
Analog supply
Analog ground
Analog ground
Not connected
Not connected
Not connected
External reset, active low
Interrupt output
Connect to ground
Digital ground
Digital supply
Digital I/O supply
Not connected
Not connected
Not connected
I2C serial clock (SCL)
I2C data in / out (SDA)
Not connected
Analog supply
Analog ground
Analog ground
Not connected
Not connected
Recommended circuit diagram
1.
2.
3.
4.
5.
Connect 100 nF SMD capacitor between each supply voltage and ground level.
Connect 1 µF capacitor between each supply voltage and ground level.
Use one regulator for analog and digital supply (AVDD and DVDD).
Use separate regulator for digital IO supply (DVIO).
Xreset is needed always in start up: when Xreset is low, raise power 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 for the SCA3000 with SPI interface is presented in Figure 15 below.
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Figure 15. Recommended circuit diagram for the SCA3000 with SPI interface.
Recommended circuit diagram for the SCA3000 with I2C interface is presented in Figure 16 below.
Figure 16. Recommended circuit diagram for the SCA3000 with I2C interface.
7.3
Recommended PWB layout
General PWB layout recommendations 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]).
Figure 17. Recommended PWB pad layout for SCA3000.
Recommended PWB layout for the SCA3000 with SPI interface is presented in Figure 18 below
(circuit diagram presented in Figure 15 above).
Figure 18. Recommended PWB layout for SCA3000 with SPI interface (not actual size, for
reference only).
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Recommended PWB layout for SCA3000 with I2C interface is presented in Figure 19 below (circuit
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
X
Earth’s
gravitation
Y
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
Offset X −axisCalibEr =
Output X −axis − Output
⋅ 1000 ,
Sens
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
Offset X − axisTempEr @ T =
Output X − axis @ T − Output X − axis @ RT
Sens
⋅1000 ,
where [email protected] is sensor’s X-axis temperature error in [mg] in temperature T, [email protected]
is sensor’s X-axis output reading [counts] in temperature T, [email protected] 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.
Pin #1
X
Y-axis in +1 g
position
Z
Y-axis in -1 g
position
Z
Earth’s
gravitation
X
Pin #1
Figure 21. SCA3000 positions for Y-axis sensitivity measurement.
Sensitivity is calculated by
Equation 4
SensY − axis =
OutputY − axis @ +1g − OutputY − axis @ −1g
2g
,
where SensY-axis is sensor’s Y-axis sensitivity in [counts/g], [email protected]+1g sensor’s Y-axis output
reading [counts] in +1 g position and [email protected] is sensor’s Y-axis output reading [counts] in -1 g
position.
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
SensY − axisCalibEr =
SensY − axis − Sens
⋅100% ,
Sens
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
SensY − axisTempEr @ T =
SensY − axis @ T − Sens Y − axis @ RT
SensY − axis @ RT
⋅100% ,
where [email protected] is sensor’s Y-axis sensitivity temperature error in [%] in temperature T, [email protected] is sensor’s measured Y-axis sensitivity [counts/g] at temperature T and [email protected] 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 range ±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 parallel to the sensor’s measuring axis.
Y
Centrifugal
acceleration
for Z-axis
Z
X
Pin #1
Figure 22. Centrifugal acceleration applied for SCA3000 Z-axis.
Linearity error is the deviation from the straight line through sensor’s sensitivity calibration points,
see Figure 23.
Acceleration reading
from SCA3000 [g]
SCA3000 linearity
error in [g] at input
acceleration acc
SCA3000 output at
positive sensitivity
calibration point
-1 g
+1 g
acc
Sensor’s ideal
output
SCA3000 output
readings
Input acceleration [g] (centrifugal
acceleration in parallel to
SCA3000 measuring axis)
Possible offset error is not
included into linearity error
Figure 23. SCA3000’s linearity error at input acceleration acc.
Linearity error is calculated by
Equation 7
LinErZ −axis @ acc =
Output Z −axis @ acc − [email protected] acc
Sens ⋅ FS
⋅100% ,
where [email protected] is sensor’s Z-axis linearity error [%FS] on input acceleration acc, OutputZ-axi[email protected]
is sensor’s measured Z-axis output [counts] on input acceleration acc, [email protected] is sensor’s
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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 [email protected] (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
[email protected] acc = acc ⋅
Output +1g − Output −1g
2g
+ offset = acc ⋅
Output +1g − Output −1g
2g
+
Output +1g + Output −1g
2
,
where [email protected] 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
n=
(
)
1 2
n X + nY2 + nZ2 ,
3
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
X
Y
Shaker
movement
in parallel
to Z-axis
Earth’s
gravitation
Pin #1
Figure 24. SCA3000 movement in Z-axis bandwidth 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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Rev.A.07
SCA3000 Series
Equation 10
S + S XZ
⋅100%,
Cross X = ± XY
SX
2
2
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
SYX + SYZ
⋅100%,
SY
2
CrossY = ±
2
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
S + S ZY
⋅ 100%,
CrossZ = ± ZX
SZ
2
2
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.
Acceleration
XRESET rise up
→ SCA3000 starts
SCA3000 output
inside ±1% FS
limits
SCA3000
Z-axis output
Time scale
Turn on time
Figure 25. Turn-on time definition for one axis.
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Rev.A.07
SCA3000 Series
9
Order Information
Order code
Description
SCA3000-D01-1
SCA3000-D01-10
SCA3000-D01-25
SCA3000-D02-1
SCA3000-D02-10
SCA3000-D02-25
SCA3000-E01-1
SCA3000-E01-10
SCA3000-E01-25
SCA3000-E02-1
SCA3000-E02-10
SCA3000-E02-25
SCA3000-E04-1
SCA3000-E04-10
SCA3000-E04-25
SCA3000-E05-1
SCA3000-E05-10
SCA3000-E05-25
SCA3000-D01 PWB
SCA3000-D02 PWB
SCA3000-E01 PWB
SCA3000-E02 PWB
SCA3000-E04 PWB
SCA3000-E05 PWB
SCA3000-D01DEMO
3-Axis accelerometer with SPI interface, +/-2g, 100 pcs
3-Axis accelerometer with SPI interface, +/-2g, 1000 pcs
3-Axis accelerometer with SPI interface, +/-2g, 2500 pcs
3-Axis accelerometer with I2C interface, +/-2g, 100 pcs
3-Axis accelerometer with I2C interface, +/-2g, 1000 pcs
3-Axis accelerometer with I2C interface, +/-2g, 2500 pcs
3-Axis accelerometer with SPI interface, +/-3g, 100 pcs
3-Axis accelerometer with SPI interface, +/-3g, 1000 pcs
3-Axis accelerometer with SPI interface, +/-3g, 2500 pcs
3-Axis accelerometer with I2C interface, +/-3g, 100 pcs
3-Axis accelerometer with I2C interface, +/-3g, 1000 pcs
3-Axis accelerometer with I2C interface, +/-3g, 2500 pcs
3-Axis accelerometer with SPI interface, +/-6g, 100 pcs
3-Axis accelerometer with SPI interface, +/-6g, 1000 pcs
3-Axis accelerometer with SPI interface, +/-6g, 2500 pcs
3-Axis accelerometer with SPI interface, +/-18g, 100 pcs
3-Axis accelerometer with SPI interface, +/-18g, 1000 pcs
3-Axis accelerometer with SPI interface, +/-18g, 2500 pcs
PWB assy, 3-Axis accelerometer with SPI interface, +/-2g
PWB assy, 3-Axis accelerometer with I2C interface, +/-2g
PWB assy, 3-Axis accelerometer with SPI interface, +/-3g
PWB assy, 3-Axis accelerometer with I2C interface, +/-3g
PWB assy, 3-Axis accelerometer with SPI interface, +/-6g
PWB assy, 3-Axis accelerometer with SPI interface, +/-18g
SCA3000-D01 DEMOKIT
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Doc.Nr. 8257300A.07
Packing
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
Bulk
Bulk
Bulk
Bulk
Bulk
Bulk
Bulk
Quantity
100
1000
2500
100
1000
2500
100
1000
2500
100
1000
2500
100
1000
2500
100
1000
2500
1
1
1
1
1
1
1
41/ 43
Rev.A.07
SCA3000 Series
10 Document Change Control
Version
Date
Change Description
0.01
....
0.08
0.09
0.10
09.09.2005
20.09.2005
23.09.2005
12.10.2005
0.11
0.12
0.13
0.14
0.15
13.10.2005
14.10.2005
01.11.2005
09.11.2005
26.01.2006
0.16
15.02.2006
0.17
14.03.2006
0.18
A
27.03.2006
27.04.2006
A.01
27.06.2006
A.02
A.03
A.04
30.6.2006
11.9.2006
27.03.2007
A.05
01.06.2007
A.06
A.07
30.10.2007
02.02.2009
Initial draft.
...
Draft release for schematic and layout design.
FF and MD description added.
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.
Typo etc minor corrections.
Draft release.
Register initial values and examples added.
Language corrections.
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.
Updated:
- absolute maximum ratings,
- temperature output equation,
2
- I C device address,
specification references
Updated:
- recommended circuit diagrams, sections “Packing” and “Handling and storage” added
Layout change
Updated:
- recommended circuit diagrams,
- sections “Packing” and “Handling and storage”
- section “Specification references” updated and renamed to “Data sheet references”
MD threshold levels
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
Order information added
SCA3000-E04 information added
Added:
- SCA3000-E04 wide band measurement mode,
- Typos corrected
- New product types: SCA3000-E05 and SCA3000-L01
Added:
- New product type: SCA3000-D03
- I2C communication added for SCA3000-L01
Corrections: typos, axis orientation
Corrected recommended PWB layouts. Removed references to D03 and L01.
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Rev.A.07
SCA3000 Series
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: [email protected]
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: [email protected]
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: [email protected]
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: [email protected]
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www.vti.fi
Doc.Nr. 8257300A.07
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: [email protected]
To find out your local sales
representative visit www.vti.fi
43/ 43
Rev.A.07
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