EVAL-ADXL343Z-M Analog Devices, EVAL-ADXL343Z-M Datasheet - Page 31

• Manufacturer Part Number: EVAL-ADXL343Z-M
• Description: Acceleration Sensor Development Tools EB
• Manufacturer: Analog Devices

Specifications of EVAL-ADXL343Z-M

• Rohs: yes
• Tool Is For Evaluation Of: ADXL343
• Acceleration: 2 g, 4 g, 8 g, 16 g
• Sensing Axis: Triple Axis
• Interface Type: I2C, SPI
• Operating Voltage: 2 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Operating Current: 140 uA
• Output Type: Digital
• Product: Evaluation Systems
• Sensitivity: 256 LSB/g, 128 LSB/g, 64 LSB/g, 32 LSG/g
• Factory Pack Quantity: 1

Data Sheet
NOISE PERFORMANCE
The specification of noise shown in Table 1 corresponds to
the typical noise performance of the
operation with an output data rate of 100 Hz (LOW_POWER bit
(D4) = 0, rate bits (D3:D0) = 0xA in the BW_RATE register,
Address 0x2C). For normal power operation at data rates below
100 Hz, the noise of the
100 Hz ODR in LSBs. For data rates greater than 100 Hz, the
noise increases roughly by a factor of √2 per doubling of the data
rate. For example, at 400 Hz ODR, the noise on the x- and y-axes
is typically less than 1.5 LSB rms, and the noise on the z-axis is
typically less than 2.2 LSB rms.
For low power operation (LOW_POWER bit (D4) = 1 in the
BW_RATE register, Address 0x2C), the noise of the
is constant for all valid data rates shown in Table 8. This value is
typically less than 1.8 LSB rms for the x- and y-axes and typically
less than 2.6LSB rms for the z-axis.
The trend of noise performance for both normal power and low
power modes of operation of the
Figure 42 shows the typical Allan deviation for the ADXL343.
The 1/f corner of the device, as shown in this figure, is very low,
allowing absolute resolution of approximately 100 µg (assuming
that there is sufficient integration time). Figure 42 also shows
that the noise density is 290 µg/√Hz for the x-axis and y-axis
and 430 µg/√Hz for the z-axis.
Figure 43 shows the typical noise performance trend of the
ADXL343
to the tested and specified supply voltage, V
noise decreases as supply voltage is increased. It should be noted, as
shown in Figure 41, that the noise on the z-axis is typically higher
than on the x-axis and y-axis; therefore, while they change roughly
the same in percentage over supply voltage, the magnitude of change
on the z-axis is greater than the magnitude of change on the
x-axis and y-axis.
Figure 41. Noise vs. Output Data Rate for Normal and Low Power Modes,
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
3.13 6.25 12.50 25
over supply voltage. The performance is normalized
X-AXIS, LOW POWER
Y-AXIS, LOW POWER
Z-AXIS, LOW POWER
X-AXIS, NORMAL POWER
Y-AXIS, NORMAL POWER
Z-AXIS, NORMAL POWER
Full-Resolution (256 LSB/g)
ADXL343
OUTPUT DATA RATE (Hz)
50
ADXL343
100 200
ADXL343
is equivalent to the noise at
400 800 1600 3200
is shown in Figure 41.
S
= 2.5 V. In general,
in normal power
ADXL343
Rev. 0 | Page 31 of 36
OPERATION AT VOLTAGES OTHER THAN 2.5 V
The
V
or as low as 2.0 V. Some performance parameters change as the
supply voltage changes: offset, sensitivity, noise, self-test, and
supply current.
Due to slight changes in the electrostatic forces as supply voltage
is varied, the offset and sensitivity change slightly. When operating
at a supply voltage of V
25 mg higher than at Vs = 2.5 V operation. The z-axis is typically
20 mg lower when operating at a supply voltage of 3.3 V than when
operating at V
shifts from a nominal 256 LSB/g (full-resolution or ±2 g, 10-bit
operation) at V
with a supply voltage of 3.3 V. The z-axis sensitivity is unaffected by
a change in supply voltage and is the same at V
as it is at V
used to determine typical shifts in offset and sensitivity at other
supply voltages.
S
= 2.5 V; however, it can be powered with V
ADXL343
10k
100
130
120
110
100
1k
10
90
80
70
0.01
2.0
S
Figure 43. Normalized Noise vs. Supply Voltage, V
= 2.5 V operation. Simple linear interpolation can be
2.2
S
is tested and specified at a supply voltage of
S
= 2.5 V. Sensitivity on the x- and y-axes typically
0.1
= 2.5 V operation to 265 LSB/g when operating
Figure 42. Root Allan Deviation
2.4
S
AVERAGING PERIOD,
SUPPLY VOLTAGE, V
= 3.3 V, the x- and y-axis offset is typically
X-AXIS
Y-AXIS
Z-AXIS
1
2.6
X-AXIS
Y-AXIS
Z-AXIS
2.8
10
3.0
S
100
(V)
(s)
3.2
S
= 3.3 V operation
S
as high as 3.6 V
1k
3.4
ADXL343
S
10k
3.6