ADXL343 データシートの表示（PDF） - Analog Devices
部品番号
コンポーネント説明
一致するリスト
ADXL343 Datasheet PDF : 36 Pages
| |||
ADXL343
SELF-TEST
The ADXL343 incorporates a self-test feature that effectively
tests its mechanical and electronic systems simultaneously.
When the self-test function is enabled (via the SELF_TEST bit
in the DATA_FORMAT register, Address 0x31), an electrostatic
force is exerted on the mechanical sensor. This electrostatic force
moves the mechanical sensing element in the same manner as
acceleration, and it is additive to the acceleration experienced
by the device. This added electrostatic force results in an output
change in the x-, y-, and z-axes. Because the electrostatic force
is proportional to VS2, the output change varies with VS. This
effect is shown in Figure 33. The scale factors shown in Table 14
can be used to adjust the expected self-test output limits for
different supply voltages, VS. The self-test feature of the
ADXL343 also exhibits a bimodal behavior. However, the limits
shown in Table 1 and Table 15 to Table 18 are valid for both
potential self-test values due to bimodality. Use of the self-test
feature at data rates less than 100 Hz or at 1600 Hz may yield
values outside these limits. Therefore, the part must be in normal
power operation (LOW_POWER bit = 0 in BW_RATE register,
Address 0x2C) and be placed into a data rate of 100 Hz through
800 Hz or 3200 Hz for the self-test function to operate correctly.
6
4
2
0
–2
X HIGH
X LOW
–4
Y HIGH
Y LOW
Z HIGH
Z LOW
–6
2.0
2.5
3.3
3.6
VS (V)
Figure 33. Self-Test Output Change Limits vs. Supply Voltage
Data Sheet
Table 14. Self-Test Output Scale Factors for Different Supply
Voltages, VS
Supply Voltage, VS (V)
X-Axis, Y-Axis
Z-Axis
2.00
0.64
0.8
2.50
1.00
1.00
3.30
1.77
1.47
3.60
2.11
1.69
Table 15. Self-Test Output in LSB for ±2 g, 10-Bit or Full
Resolution (TA = 25°C, VS = 2.5 V, VDD I/O = 1.8 V)
Axis
Min
Max
Unit
X
50
540
LSB
Y
−540
−50
LSB
Z
75
875
LSB
Table 16. Self-Test Output in LSB for ±4 g, 10-Bit Resolution
(TA = 25°C, VS = 2.5 V, VDD I/O = 1.8 V)
Axis
Min
Max
Unit
X
25
270
LSB
Y
−270
−25
LSB
Z
38
438
LSB
Table 17. Self-Test Output in LSB for ±8 g, 10-Bit Resolution
(TA = 25°C, VS = 2.5 V, VDD I/O = 1.8 V)
Axis
Min
Max
Unit
X
12
135
LSB
Y
−135
−12
LSB
Z
19
219
LSB
Table 18. Self-Test Output in LSB for ±16 g, 10-Bit Resolution
(TA = 25°C, VS = 2.5 V, VDD I/O = 1.8 V)
Axis
Min
Max
Unit
X
6
67
LSB
Y
−67
−6
LSB
Z
10
110
LSB
Rev. 0 | Page 20 of 36
Share Link: 