công cụ tìm kiếm bảng dữ liệu linh kiện điện tử
  Vietnamese  ▼
ALLDATASHEET.VN

X  

ADXL250JQC bảng dữ liệu(PDF) 10 Page - Analog Devices

tên linh kiện ADXL250JQC
Giải thích chi tiết về linh kiện  -5 g to -50 g, Low Noise, Low Power, Single/Dual Axis iMEMS Accelerometers
Download  15 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
nhà sản xuất  AD [Analog Devices]
Trang chủ  http://www.analog.com
Logo AD - Analog Devices

ADXL250JQC bảng dữ liệu(HTML) 10 Page - Analog Devices

Back Button ADXL250JQC Datasheet HTML 6Page - Analog Devices ADXL250JQC Datasheet HTML 7Page - Analog Devices ADXL250JQC Datasheet HTML 8Page - Analog Devices ADXL250JQC Datasheet HTML 9Page - Analog Devices ADXL250JQC Datasheet HTML 10Page - Analog Devices ADXL250JQC Datasheet HTML 11Page - Analog Devices ADXL250JQC Datasheet HTML 12Page - Analog Devices ADXL250JQC Datasheet HTML 13Page - Analog Devices ADXL250JQC Datasheet HTML 14Page - Analog Devices Next Button
Zoom Inzoom in Zoom Outzoom out
 10 / 15 page
background image
–10–
ADXL150/ADXL250
REV. 0
DEVICE BANDWIDTH VS. MEASUREMENT
RESOLUTION
Although an accelerometer is usually specified according to its
full-scale g level, the limiting resolution of the device, i.e., its
minimum discernible input level, is extremely important when
measuring low g accelerations.
3dB BANDWIDTH – Hz
100m
g
1m
g
10m
g
10
1k
100
660m
g
66m
g
6.6m
g
Figure 19. ADXL150/ADXL250 Noise Level vs. 3 dB
Bandwidth (Using a “Brickwall” Filter)
The limiting resolution is predominantly set by the measure-
ment noise “floor,” which includes the ambient background
noise and the noise of the ADXL150/ADXL250 itself. The level
of the noise floor varies directly with the bandwidth of the mea-
surement. As the measurement bandwidth is reduced, the noise
floor drops, improving the signal-to-noise ratio of the measure-
ment and increasing its resolution.
The bandwidth of the accelerometer can be easily reduced by
adding low-pass or bandpass filtering. Figure 19 shows the
typical noise vs. bandwidth characteristic of the ADXL150/
ADXL250.
The output noise of the ADXL150/ADXL250 scales with the
square root of the measurement bandwidth. With a single pole
roll-off, the equivalent rms noise bandwidth is
π divided by 2 or
approximately 1.6 times the 3 dB bandwidth. For example, the
typical rms noise of the ADXL150 using a 100 Hz one pole post
filter is:
Noise rms
()=1mg/ Hz × 100 1.6
()=12.25mg
Because the ADXL150/ADXL250’s noise is, for all practical
purposes, Gaussian in amplitude distribution, the highest noise
amplitudes have the smallest (yet nonzero) probability. Peak-
to-peak noise is therefore difficult to measure and can only be
estimated due to its statistical nature. Table I is useful for esti-
mating the probabilities of exceeding various peak values, given
the rms value.
Table I.
Nominal Peak-to-
% of Time that Noise Will Exceed
Peak Value
Nominal Peak-to-Peak Value
2.0
× rms
32%
4.0
× rms
4.6%
6.0
× rms
0.27%
6.6
× rms
0.1%
8.0
× rms
0.006%
RMS and peak-to-peak noise (for 0.1% uncertainty) for various
bandwidths are estimated in Figure 19. As shown by the figure,
device noise drops dramatically as the operating bandwidth is
reduced. For example, when operated in a 1 kHz bandwidth,
the ADXL150/ADXL250 typically have an rms noise level of
32 mg. When the device bandwidth is rolled off to 100 Hz, the
noise level is reduced to approximately 10 mg.
Alternatively, the signal-to-noise ratio may be improved consid-
erably by using a microprocessor to perform multiple measure-
ments and then to compute the average signal level.
Low-Pass Filtering
The bandwidth of the accelerometer can easily be reduced by using
post filtering. Figure 20 shows how the buffer amplifier can be
connected to provide 1-pole post filtering, zero g offset trimming,
and output scaling. The table provides practical component values
Cf
R2
1M
+VS
RT
200k
0
g TRIM
SCALE
FACTOR
TRIM
(OPTIONAL)
R3
100k
+VS
0.1 F
R1a
75k
VOUT
0.1 F
+VS
2
SELF-TEST
25k
5k
ADXL150
GAIN
AMP
OFFSET
NULL
COM
C1
0.1 F
BUFFER
AMP
DEMODULATOR
SENSOR
+VS
TP
(DO NOT CONNECT)
14
9
10
7
5
CLOCK
OP196
3
4
6
2
8
7
+VS
2
R1b
50k
EXT
AMP
GAIN
R3
VALUE
F.S.
RANGE
DESIRED
OUTPUT
SCALE FACTOR
Cf ( F)
100Hz
Cf ( F)
30Hz
Cf ( F)
10Hz
0.0082
0.0056
0.0033
0.0015
0.027
0.022
0.010
0.0056
0.082
0.056
0.033
0.015
76mV/
g
25
g
2.0
200k
100mV/
g
20
g
2.6
261k
200mV/
g
10
g
5.3
536k
400mV/
g
5
g
10.5
1M
Figure 20. One-Pole Post Filter Circuit with SF and Zero g Offset Trims


Số phần tương tự - ADXL250JQC

nhà sản xuấttên linh kiệnbảng dữ liệuGiải thích chi tiết về linh kiện
logo
Analog Devices
ADXL251 AD-ADXL251 Datasheet
103Kb / 2P
   Dual-Axis, 60 g to 480 g Sensor with SPI and PSI5
More results

Mô tả tương tự - ADXL250JQC

nhà sản xuấttên linh kiệnbảng dữ liệuGiải thích chi tiết về linh kiện
logo
Analog Devices
ADXL78 AD-ADXL78 Datasheet
190Kb / 12P
   Single-Axis, High-g, iMEMS Accelerometers
REV. A
ADXL193 AD-ADXL193 Datasheet
180Kb / 12P
   Single-Axis, High-g, iMEMS Accelerometers
REV. A
ADXL278 AD-ADXL278_15 Datasheet
169Kb / 12P
   Dual-Axis, High-g, iMEMS Accelerometers
ADXL193 AD-ADXL193_15 Datasheet
154Kb / 12P
   Single-Axis, High-g, iMEMS Accelerometers
REV. B
ADXL78 AD-ADXL78_15 Datasheet
171Kb / 12P
   Single-Axis, High-g, iMEMS Accelerometers
Rev. B
ADXL202 AD-ADXL202 Datasheet
124Kb / 11P
   Low Cost -2 g/-10 g Dual Axis iMEMS Accelerometers with Digital Output
REV. B
ADXL203 AD-ADXL203_15 Datasheet
853Kb / 16P
   Precision 1.7 g, 5 g, 18 g Single-/ Dual-Axis iMEMS Accelerometer
ADXL103 AD-ADXL103_15 Datasheet
853Kb / 16P
   Precision 1.7 g, 5 g, 18 g Single-/ Dual-Axis iMEMS Accelerometer
Rev. E
AD22301 AD-AD22301 Datasheet
171Kb / 12P
   Single-Axis, High-g, iMEMS ccelerometers
REV. B
ADXL323 AD-ADXL323_15 Datasheet
461Kb / 16P
   Small, Low Power, 2-Axis 3 g iMEMS Accelerometer
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15


bảng dữ liệu tải về

Go To PDF Page


Link URL




Chính sách bảo mật
ALLDATASHEET.VN
Cho đến nay ALLDATASHEET có giúp ích cho doanh nghiệp của bạn hay không?  [ DONATE ] 

Alldatasheet là   |   Quảng cáo   |   Liên lạc với chúng tôi   |   Chính sách bảo mật   |   Trao đổi link   |   Tìm kiếm theo nhà sản xuất
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com