Analog Devices ADXL213 Datasheet
Low Cost ±1.2 g Dual
C
FEATURES
Dual axis accelerometer on a single IC chip
5 mm × 5 mm × 2 mm LCC package
1 mg resolution at 60 Hz
Low power: 700 µA at V
High zero g bias stability
High sensitivity accuracy
Pulse width modulated digital outputs
X and Y axes aligned to within 0.1° (typical)
BW adjustment with a single capacitor
Single-supply operation
3500 g shock survival
APPLICATIONS
Automotive tilt alarms
Data projectors
Navigation
Platform stabilization/leveling
Alarms and motion detectors
High accuracy, 2-axis tilt sensing
= 5 V (typical)
S
Axis Accelerometer
ADXL213
GENERAL DESCRIPTION
The ADXL213 is a low cost, low power, complete dual axis
accelerometer with signal conditioned, duty cycle modulated
outputs, all on a single monolithic IC. The ADXL213 measures
acceleration with a full-scale range of ±1.2 g (typical). The
ADXL213 can measure both dynamic acceleration (e.g.,
vibration) and static acceleration (e.g., gravity).
The outputs are digital signals whose duty cycles (ratio of pulse
width to period) are proportional to acceleration (30%/g). The
duty cycle outputs can be directly measured by a microcontroller without an A/D converter or glue logic.
Innovative design techniques are used to ensure high zero g bias
stability (typically better than 0.25 mg/°C), as well as tight sensitivity stability (typically better than 50 ppm/°C).
The typical noise floor is 160 µg/√
1 mg (0.06° of inclination) to be resolved in tilt sensing applica-
tions using narrow bandwidths (<60 Hz).
The user selects the bandwidth of the accelerometer using
capacitors C
and CY at the X
X
FILT
0.5 Hz to 250 Hz may be selected to suit the application.
, allowing signals below
Hz
and Y
pins. Bandwidths of
FILT
FUNCTIONAL BLOCK DIAGRAM
+V
S
+V
S
ADXL213
DC
SENSOR
COM ST X
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
AC
AMP
DEMOD
Figure 1.
The ADXL213 is available in a 5 mm × 5 mm × 2 mm, 8-pad
hermetic LCC package.
C
Y
Y
FILT
32kΩ
OUTPUT
AMP
OUTPUT
AMP
32kΩ
T1
A(g) = (T1/T2 – 0.5)/30%
0g = 50% DUTY CYCLE
T2(s) = R
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved.
DCM
FILT
C
X
T2
/125MΩ
SET
www.analog.com
Y
OUT
X
OUT
T2
R
SET
04742-0-001
ADXL213
TABLE OF CONTENTS
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 4
Typical Performance Characteristics............................................. 5
Theory of Operation ........................................................................ 8
Performance.................................................................................. 8
Applications....................................................................................... 9
Power Supply Decoupling........................................................... 9
Setting the Bandwidth Using CX and CY.................................... 9
Self Test.......................................................................................... 9
REVISION HISTORY
Revision 0: Initial Version
Design Trade-Offs for Selecting Filter Characteristics:
The Noise/BW Trade-Off........................................................9
Using the ADXL213 with Operating Voltages Other
than 5 V................................................................................... 10
Using the ADXL213 as a Dual-Axis Tilt Sensor..................... 10
Pin Configurations and Functional Descriptions...................... 11
Outline Dimensions....................................................................... 12
ESD Caution................................................................................ 12
Ordering Guide .......................................................................... 12
Rev. 0 | Page 2 of 12
ADXL213
SPECIFICATIONS
TA = –40°C to +85°C, VS = 5 V, CX = CY = 0.1 μF, Acceleration = 0 g, unless otherwise noted. All minimum and maximum specifications
are guaranteed. Typical specifications are not guaranteed.
Table 1.
Parameter Conditions Min Typ Max Unit
SENSOR INPUT Each axis
Measurement Range
Nonlinearity % of full scale ±0.5 %
Package Alignment Error ±1 Degrees
Alignment Error X sensor to Y sensor ±0.1 Degrees
Cross Axis Sensitivity ±2 %
SENSITIVITY (Ratiometric)
Sensitivity at X
Sensitivity Change due to Temperature
ZERO g BIAS LEVEL (Ratiometric) Each axis
0 g Voltage at X
Initial 0 g Output Deviation from Ideal VS = 5 V, 25°C ±2 %
0 g Offset vs. Temperature ±0.25 mg/°C
NOISE PERFORMANCE
Noise Density @25°C
FREQUENCY RESPONSE
CX, CY Range
R
Tolerance 22 32 42 kΩ
FILT
5
Sensor Resonant Frequency 5.5 kHz
SELF TEST
6
Logic Input Low 1 V
Logic Input High 4 V
ST Input Resistance to Ground 30 50 kΩ
Output Change at X
PWM Output
F
SET
T2 Drift versus Temperature ±0.3 %
POWER SUPPLY
Operating Voltage Range 3 6 V
Quiescent Supply Current 0.7 1.1 mA
Turn-On Time
OUT
OUT
, Y
, Y
OUT
1
OUT
4
±1.2
2
Each axis
VS = 5 V 27 30 33 %/g
3
VS = 5 V ±0.3 %
VS = 5 V ±50 %
160
g
µg/√
Hz rms
0.002 4.7 µF
, Y
OUT
OUT
7
Self test 0 to 1 23 %
R
= 125 kΩ 1 kHz
SET
20 ms
1
Guaranteed by measurement of initial offset and sensitivity.
2
Sensitivity varies with VS. At VS = 3 V, sensitivity is typically 28%/g.
3
Defined as the output change from ambient-to-maximum temperature or ambient-to-minimum temperature.
4
Actual frequency response controlled by user-supplied external capacitor (CX, CY).
5
Bandwidth = 1/(2 × π × 32 kΩ × C). For CX, CY = 0.002 µF, Bandwidth = 2500 Hz. For CX, CY = 4.7 µF, Bandwidth = 1 Hz. Minimum/maximum values are not tested.
6
Self-test response changes with VS. At VS = 3 V, self-test output is typically 8%.
7
Larger values of CX, CY increase turn-on time. Turn-on time is approximately 160 × CX or CY + 4 ms, where CX, CY are in µF.
Rev. 0 | Page 3 of 12
ADXL213
ABSOLUTE MAXIMUM RATINGS
Table 2. ADXL213 Stress Ratings
Parameter Rating
Acceleration (Any Axis, Unpowered) 3,500 g
Acceleration (Any Axis, Powered) 3,500 g
Drop Test (Concrete Surface) 1.2 m
V
S
All Other Pins
–0.3 V to +7.0 V
(COM – 0.3 V) to
+ 0.3 V)
(V
S
Output Short-Circuit Duration
(Any Pin to Common) Indefinite
Operating Temperature Range –55°C to +125°C
Storage Temperature –65°C to +150°C
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
T
P
T
L
T
SMAX
RAMP-UP
Table 3. Package Characteristics
Package Type θ
8-Lead CLCC 120°C/W 20°C/W <1.0 gram
t
P
t
L
JA
CRITICAL ZONE
TO T
T
L
P
θ
JC
Device Weight
T
SMIN
TEMPERATURE
t
S
PREHEAT
t
25°C TO PEAK
TIME
RAMP-DOWN
03757-0-002
Condition
Profile Feature
Sn63/Pb37 Pb Free
Average Ramp Rate (TL to TP) 3°C/second max
Preheat
• Minimum Temperature (T
• Minimum Temperature (T
• Time (T
T
to T
SMAX
to T
SMAX
) (tS)
SMIN
L
• Ramp-Up Rate
SMIN
SMAX
)
)
100°C 150°C
150°C 200°C
60–120 seconds 60–150 seconds
3°C/second
Time Maintained above Liquidous (TL)
• Liquidous Temperature (T
• Time (t
)
L
)
L
183°C 217°C
60–150 seconds 60–150 seconds
Peak Temperature (TP) 240°C +0°C/–5°C 260°C +0°C/–5°C
Time within 5°C of Actual Peak Temperature (tP) 10–30 seconds 20–40 seconds
Ramp-Down Rate 6°C/second max
Time 25°C to Peak Temperature 6 minutes max 8 minutes max
Figure 2. Recommended Soldering Profile
Rev. 0 | Page 4 of 12
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