SCA3000 Series
SCA3000-L01
Table 2. Available measurement modes for SCA3000.
Available measurement
modes
SCA3000-D01
SCA3000-D02
SCA3000-E01
SCA3000-E02
Measurement
mode
SCA3000-D03
SCA3000-E04
SCA3000-E05
Default after power-on
or reset
Measurement
mode
Measurement
mode
Measurement
mode
Measurement
mode
Measurement
mode
Bypass
Narrow band
measurement
mode
Narrow band
measurement
mode
Narrow band
measurement
mode
Bypass
Optional measurement
mode 1
measurement
mode
Not available
Not available
measurement
mode
Wide band
measurement
mode
Wide band
measurement
mode
Optional measurement
mode 2
Not available
Not available
Not available
2.2.1.1 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
LSB byte
Bit number
B7 B6 B5 B4 B3 B2 B1 B0 B7 B6 B5 B4 B3 B2:B0
Acceleration data bit Sign d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0
Data overflow on
0
1
1
x
x
x
x
x
x
x
x
x
x
xxx
xxx
positive acceleration
Data overflow on
negative
1
0
0
x
x
x
x
x
x
x
x
x
x
acceleration
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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