Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

ADXL05 Datasheet(PDF) 12 Page - Analog Devices

Part No. ADXL05
Description  Single Chip Accelerometer with Signal Conditioning
Download  20 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  AD [Analog Devices]
Homepage  http://www.analog.com
Logo 

ADXL05 Datasheet(HTML) 12 Page - Analog Devices

Zoom Inzoom in Zoom Outzoom out
 12 / 20 page
background image
ADXL05
REV. B
–12–
With a dc coupled connection, any difference between a non-
ideal +1.8 V 0 g level at VPR and the fixed +1.8 V level at the
buffer’s summing junction will be amplified by the gain of the
buffer. If the 0 g level only needs to be approximate and the
buffer is operated a low gain, a single fixed resistor, R2, can still
be used. But to obtain the exact 0 g output desired or to allow
the maximum output voltage swing from the buffer, the 0 g
offset will need to be externally trimmed using the circuit of Fig-
ure 23. Normally, a value of 100 k
Ω is typical for R2.
The buffer’s maximum output swing should be limited to
±2 volts, which provides a safety margin of ±0.25 volts before
clipping. With a +2.5 volt 0 g level, the maximum gain the
buffer should be set to (R3/R1) equals:
2Volts
200 mV/g Times the Max Applied Acceleration in gs
Note that the value of R1 should be kept as large as possible,
20 k
Ω or greater, to avoid loading down the V
PR output.
The device scale factor and 0 g offset levels can be calibrated us-
ing the Earth’s gravity as explained in the section “calibrating
the ADXL05.”
BUFFER
AMP
0.1µF
+5V
VOUT
0.022µF
C1
C1
+3.4V
REF
COM
1.8V
8
9
10
1
2
3
4
0.022µF
C2
PRE-AMP
VPR
R1
R3
VIN–
5
ADXL05
6
R2
100k
0
g
LEVEL
TRIM
50k
S.F. =
R3
R1
R1
20kΩ
VX
FULL
SCALE
±1g
±2g
±4g
±5g
mV
per
g
2000
1000
500
400
R1
k
30.1
40.2
40.2
49.2
R3
k
301
200
100
100
RECOMMENDED COMPONENT VALUES FOR
VARIOUS OUTPUT SCALE FACTORS
Figure 23. Typical Component Values for Circuit with
External 0 g Trimming
BUFFER
AMP
C3
0.1µF
+5V
VOUT
0.022µF
C1
C1
+3.4V
REF
COM
1.8V
6
8
9
1
2
3
4
0.022µF
C2
PRE-AMP
VPR
R1
R3
VIN–
5
ADXL05
10
C4
R2
SCALE FACTOR =
R3
R1
1
2
πR1 FL
C4 =
FOR A +2.5V 0
g LEVEL,
IN AN AC COUPLED
CONFIGURATION,
R2 = 2.57 R3
FULL
SCALE
RANGE
±2g
±5g
±2g
±5g
±5g
SCALE
FACTOR
IN
mV/
g
1000
400
1000
400
400
DESIRED
LOW
FREQUENCY
LIMIT, FL
R1
IN
k
49.9
127
49.9
127
127
CLOSEST
C4
VALUE
0.10µF
0.039µF
1.0µF
1.5µF
15µF
R2 VALUE
IN k
Ω FOR
+2.5V 0
g
LEVEL
640
640
640
640
640
R3
IN
k
249
249
249
249
249
RECOMMENDED COMPONENT VALUES
30Hz
30Hz
3Hz
1Hz
0.1Hz
Figure 22. Typical Component Values for AC Coupled
Circuit
In order to force this current through R3, the same current
needs to flow from Pin 10 to ground through resistor R2. Since
Pin 10 is always held at +1.8 V, R2 is equal to:
R2
= 1.8 Volts
IR 3
Therefore, for an ac coupled connection and a +2.5 V 0 g
output:
R2
= 1.8Volts × R3
0.7Volts
= 2.57 × R3
If ac coupling is used, the self-test feature must be monitored at
VPR, rather than at the buffer output (since the self test output is
a dc voltage).
Setting the Accelerometer’s 0 g Bias Level, DC Coupled
Response
When a true dc (gravity) response is needed, the output from
the preamplifier, VPR, must be dc coupled to the buffer input.
For high gain applications, a 0 g offset trim will also be needed.
The external offset trim permits the user to set the 0 g offset
voltage to exactly +2.5 volts, since this is at the center of the +5
volt power supply it will allow the maximum output swing from
the buffer without clipping.
OBSOLETE


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   Link Exchange   |   Manufacturer List
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