AD AD22293Z Precision â±1.7 g, â±5 g, â±18 g single-/ dual-axis imemsâ® accelerometer Datasheet

Precision ±1.7 g, ±5 g, ±18 g Single-/
Dual-Axis iMEMS® Accelerometer
ADXL103/ADXL203
Data Sheet
FEATURES
GENERAL DESCRIPTION
High performance, single-/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 VS = 5 V (typical)
High zero g bias stability
High sensitivity accuracy
−40°C to +125°C temperature range
X and Y axes aligned to within 0.1° (typical)
Bandwidth adjustment with a single capacitor
Single-supply operation
3500 g shock survival
RoHS compliant
Compatible with Sn/Pb- and Pb-free solder processes
Qualified for automotive applications
The ADXL103/ADXL203 are high precision, low power, complete
single- and dual-axis accelerometers with signal conditioned
voltage outputs, all on a single, monolithic IC. The ADXL103/
ADXL203 measure acceleration with a full-scale range of ±1.7 g,
±5 g, or ±18 g. The ADXL103/ADXL203 can measure both
dynamic acceleration (for example, vibration) and static
acceleration (for example, gravity).
The typical noise floor is 110 μg/√Hz, allowing signals below 1 mg
(0.06° of inclination) to be resolved in tilt sensing applications
using narrow bandwidths (<60 Hz).
The user selects the bandwidth of the accelerometer using
Capacitor CX and Capacitor CY at the XOUT and YOUT pins.
Bandwidths of 0.5 Hz to 2.5 kHz can be selected to suit the
application.
The ADXL103 and ADXL203 are available in a 5 mm × 5 mm ×
2 mm, 8-terminal ceramic LCC package.
APPLICATIONS
Vehicle dynamic controls
Electronic chassis controls
Platform stabilization/leveling
Navigation
Alarms and motion detectors
High accuracy, 2-axis tilt sensing
Vibration monitoring and compensation
Abuse event detection
FUNCTIONAL BLOCK DIAGRAMS
+5V
+5V
VS
VS
ADXL203
ADXL103
AC
AMP
DEMOD
OUTPUT
AMP
CDC
SENSOR
AC
AMP
OUTPUT
AMP
OUTPUT
AMP
SENSOR
RFILT
32kΩ
COM
DEMOD
ST
RFILT
32kΩ
XOUT
COM
CX
ST
RFILT
32kΩ
YOUT
XOUT
CY
CX
03757-001
CDC
Figure 1.
Rev. D
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.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©2004–2011 Analog Devices, Inc. All rights reserved.
ADXL103/ADXL203
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Performance................................................................................ 13
Applications....................................................................................... 1
Applications Information .............................................................. 14
General Description ......................................................................... 1
Power Supply Decoupling ......................................................... 14
Functional Block Diagrams............................................................. 1
Setting the Bandwidth Using CX and CY ................................. 14
Specifications..................................................................................... 3
Self Test ........................................................................................ 14
Absolute Maximum Ratings............................................................ 4
Design Trade-Offs for Selecting Filter Characteristics: The
Noise/Bandwidth Trade-Off ..................................................... 14
ESD Caution.................................................................................. 4
Pin Configurations and Function Descriptions ........................... 5
Typical Performance Characteristics ............................................. 6
ADXL103 and ADXL203............................................................. 6
AD22293........................................................................................ 9
AD22035 and AD22037 ............................................................ 10
All Models ................................................................................... 12
Using the ADXL103/ADXL203 with Operating Voltages
Other than 5 V............................................................................ 15
Using the ADXL203 as a Dual-Axis Tilt Sensor ........................ 15
Outline Dimensions ....................................................................... 16
Ordering Guide .......................................................................... 16
Automotive Products ................................................................. 16
Theory of Operation ...................................................................... 13
REVISION HISTORY
9/11—Rev. C to Rev. D
Added AD22293, AD22035, and AD22037 ............... Throughout
Changes to Application Section and General Description
Section................................................................................................ 1
Changes to Table 1............................................................................ 3
Deleted Figure 13 and Figure 14: Renumbered Sequentially ..... 7
Deleted Figure 17 and Figure 22..................................................... 8
Added Figure 19 to Figure 24; Renumbered Sequentially .......... 9
Added Figure 25 to Figure 34........................................................ 10
Added All Models Section, Figure 35 to Figure 38 .................... 12
Changes to Figure 39...................................................................... 13
Changes to Ordering Guide .......................................................... 16
Changes to Automotive Products Section................................... 16
4/10—Rev. A to Rev. B
Changes to Features Section ............................................................1
Updated Outline Dimensions....................................................... 12
Changes to Ordering Guide .......................................................... 12
2/06—Rev. 0 to Rev. A
Changes to Features ..........................................................................1
Changes to Table 1.............................................................................3
Changes to Figure 2...........................................................................4
Changes to Figure 3 and Figure 4....................................................5
Changes to the Performance Section..............................................9
4/04—Revision 0: Initial Version
5/10—Rev. B to Rev. C
Changes to Figure 24 Caption....................................................... 12
Added Automotive Products Section .......................................... 12
Rev. D | Page 2 of 16
Data Sheet
ADXL103/ADXL203
SPECIFICATIONS
TA = −40°C to +125°C, VS = 5 V, CX = CY = 0.1 μF, acceleration = 0 g, unless otherwise noted. All minimum and maximum specifications
are guaranteed. All typical specifications are not guaranteed.
Table 1.
Parameter
SENSOR
Measurement Range 1
Nonlinearity
Package Alignment Error
Alignment Error (ADXL203)
Cross-Axis Sensitivity
SENSITIVITY (RATIOMETRIC) 2
Sensitivity at XOUT, YOUT
Sensitivity Change Due to
Temperature 3
ZERO g BIAS LEVEL (RATIOMETRIC)
0 g Voltage at XOUT, YOUT
Initial 0 g Output Deviation
From Ideal
0 g Offset vs. Temperature
NOISE
Output Noise
Noise Density
FREQUENCY RESPONSE 4
CX, CY Range 5
RFILT Tolerance
Sensor Resonant Frequency
SELF TEST 6
Logic Input Low
Logic Input High
ST Input Resistance to GND
Output Change at XOUT, YOUT
OUTPUT AMPLIFIER
Output Swing Low
Output Swing High
POWER SUPPLY (VDD)
Operating Voltage Range
Quiescent Supply Current
Turn-On Time 7
Test Conditions
Each axis
ADXL103/ADXL203
Min
Typ
Max
Min
±1.7
±5
% of full scale
X to Y sensor
±0.2
±1
±0.1
±1.5
±1.25
±3
AD22293
Typ Max
±6
±0.2
±1
±0.1
±1.5
AD22035/AD22037
Min
Typ
Max
±18
±1.25
±3
±0.2
±1
±0.1
±1.5
±1.25
±3
Unit
g
%
Degrees
Degrees
%
Each axis
VS = 5 V
VS = 5 V
960
1000
±0.3
1040
293
312
±0.3
331
94
100
±0.3
106
mV/g
%
Each axis
VS = 5 V
VS = 5 V, 25°C
2.4
2.5
±25
2.6
2.4
2.5
±50
2.6
2.4
2.5
±125
2.6
V
mg
±0.1
±0.8
±0.3
±1.8
1
110
3
1
200
3
<4 kHz, VS = 5 V
0.002
24
32
5.5
10
40
0.002
24
32
5.5
1
ST 0 to ST 1
No load
No load
4
30
450
0.05
50
750
1100
0.2
4.5
4.8
3
0.7
20
1
10
40
50
250
375
0.2
4.5
4.8
3
0.7
20
mg/°C
2
mV rms
μg/√Hz
rms
10
40
μF
kΩ
kHz
1
130
0.002
24
32
5.5
1
4
30
125
0.05
6
1.1
±1
4
30
60
0.05
6
1.1
50
80
100
V
V
kΩ
mV
0.2
4.5
4.8
V
V
3
0.7
20
6
1.1
V
mA
ms
Guaranteed by measurement of initial offset and sensitivity.
Sensitivity is essentially ratiometric to VS. For VS = 4.75 V to 5.25 V, sensitivity is 186 mV/V/g to 215 mV/V/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 = 10 μF, bandwidth = 0.5 Hz. Minimum/maximum values are not tested.
6
Self-test response changes cubically with VS.
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.
2
Rev. D | Page 3 of 16
ADXL103/ADXL203
Data Sheet
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter
Acceleration (Any Axis, Unpowered)
Acceleration (Any Axis, Powered)
Drop Test (Concrete Surface)
VS
All Other Pins
Rating
3500 g
3500 g
1.2 m
−0.3 V to +7.0 V
(COM − 0.3 V) to
(VS + 0.3 V)
Indefinite
Output Short-Circuit Duration
(Any Pin to Common)
Temperature Range (Powered)
Temperature Range (Storage)
Table 3. Package Characteristics
Package Type
8-Terminal Ceramic LCC
θJA
120°C/W
θJC
20°C/W
Device Weight
<1.0 gram
ESD CAUTION
−55°C to +125°C
−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.
CRITICAL ZONE
TL TO TP
tP
TP
TEMPERATURE
RAMP-UP
TL
tL
TSMAX
TSMIN
tS
RAMP-DOWN
03757-102
PREHEAT
t25°C TO PEAK
TIME
Figure 2. Recommended Soldering Profile
Table 4. Solder Profile Parameters
Test Condition
Profile Feature
Average Ramp Rate (TL to TP)
Preheat
Minimum Temperature (TSMIN)
Maximum Temperature (TSMAX)
Time (TSMIN to TSMAX) (tS)
TSMAX to TL
Ramp-Up Rate
Time Maintained above Liquidous (TL)
Liquidous Temperature (TL)
Time (tL)
Peak Temperature (TP)
Time Within 5°C of Actual Peak Temperature (tP)
Ramp-Down Rate
Time 25°C to Peak Temperature
Sn63/Pb37
3°C/second maximum
Pb-Free
3°C/second maximum
100°C
150°C
60 seconds to 120 seconds
150°C
200°C
60 seconds to 150 seconds
3°C/second
3°C/second
183°C
60 seconds to 150 seconds
240°C + 0°C/−5°C
10 seconds to 30 seconds
6°C/second maximum
6 minutes maximum
217°C
60 seconds to 150 seconds
260°C + 0°C/−5°C
20 seconds to 40 seconds
6°C/second maximum
8 minutes maximum
Rev. D | Page 4 of 16
Data Sheet
ADXL103/ADXL203
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
ADXL103
ADXL203
TOP VIEW
(Not to Scale)
TOP VIEW
(Not to Scale)
VS
VS
8
+X
COM 3
4
NC
XOUT
ST 1
6
NC
NC 2
5
NC
COM 3
+Y
+X
4
NC
7
XOUT
6
YOUT
5
NC
03757-003
NC 2
8
7
03757-002
ST 1
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN.
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN.
Figure 3. ADXL103 Pin Configuration
Figure 4. ADXL203 Pin Configuration
Table 5. ADXL103 Pin Function Descriptions
Table 6. ADXL203 Pin Function Descriptions
Pin No.
1
2
3
4
5
6
7
8
Pin No.
1
2
3
4
5
6
7
8
Mnemonic
ST
NC
COM
NC
NC
NC
XOUT
VS
Description
Self Test
Do Not Connect
Common
Do Not Connect
Do Not Connect
Do Not Connect
X Channel Output
3 V to 6 V
Rev. D | Page 5 of 16
Mnemonic
ST
NC
COM
NC
NC
YOUT
XOUT
VS
Description
Self Test
Do Not Connect
Common
Do Not Connect
Do Not Connect
Y Channel Output
X Channel Output
3 V to 6 V
ADXL103/ADXL203
Data Sheet
TYPICAL PERFORMANCE CHARACTERISTICS
ADXL103 AND ADXL203
VS = 5 V for all graphs, unless otherwise noted.
30
25
10
ZERO g BIAS (V)
Figure 8. Y-Axis Zero g Bias Deviation from Ideal at 25°C
30
25
35
35
PERCENT OF POPULATION (%)
40
30
25
20
15
10
0.80
0.70
0.60
0.50
0.40
–0.10
–0.20
–0.30
25
20
15
10
SENSITIVITY (V/g)
Figure 10. Y-Axis Sensitivity at 25°C
Rev. D | Page 6 of 16
1.06
1.05
03757-015
SENSITIVITY (V/g)
Figure 7. X-Axis Sensitivity at 25°C
1.04
1.03
1.02
1.01
1.00
0.99
0.98
0.97
0.96
0.95
0.94
0
1.06
1.05
1.04
1.03
1.02
1.01
1.00
0.99
0.98
0.97
30
5
03757-012
5
0.96
–0.40
Figure 9. Y-Axis Zero g Bias Temperature Coefficient
40
0.95
–0.50
TEMPERATURE COEFFICIENT (mg/°C)
Figure 6. X-Axis Zero g Bias Temperature Coefficient
0.94
–0.60
–0.70
–0.80
TEMPERATURE COEFFICIENT (mg/°C)
0.30
03757-014
5
0
0.80
0.70
0.60
0.50
0.40
0.30
0.20
–0.10
–0.20
–0.30
–0.40
–0.60
–0.50
–0.70
–0.80
0
0
03757-011
5
10
0.20
10
15
0
15
20
0.10
PERCENT OF POPULATION (%)
20
0.10
PERCENT OF POPULATION (%)
25
PERCENT OF POPULATION (%)
0.10
ZERO g BIAS (V)
Figure 5. X-Axis Zero g Bias Deviation from Ideal at 25°C
0
0
–0.02
–0.04
–0.06
–0.10
–0.08
0
0.08
03757-013
5
0.10
0.08
0.06
0
–0.02
–0.04
–0.06
–0.08
–0.10
0
0.04
03757-010
5
15
0.06
10
20
0.04
15
0.02
PERCENT OF POPULATION (%)
20
0.02
PERCENT OF POPULATION (%)
25
Data Sheet
ADXL103/ADXL203
2.60
1.03
2.58
1.02
2.56
SENSITIVITY (V/g)
2.52
2.50
2.48
2.46
2.44
0.99
50
45
45
40
40
35
30
25
20
15
03757-007
10
60
70
80
90
100 110 120 130
X AXIS NOISE DENSITY (mg/√Hz)
140
03757-016
120
110
90
100
80
70
60
50
40
30
20
0
10
–10
–20
35
30
25
20
15
10
03757-008
PERCENT OF POPULATION (%)
50
0
–30
–50
Figure 13. Sensitivity vs. Temperature; Parts Soldered to PCB
Figure 11. Zero g Bias vs. Temperature; Parts Soldered to PCB
5
TEMPERATURE (°C)
130
03757-004
0.97
130
120
110
90
TEMPERATURE (°C)
100
80
70
60
50
40
30
20
0
10
–10
–20
–30
–40
2.40
–50
1.00
0.98
2.42
PERCENT OF POPULATION (%)
1.01
–40
VOLTAGE (1V/g)
2.54
5
0
150
60
70
80
90
100 110 120 130
Y AXIS NOISE DENSITY (mg/√Hz)
Figure 14. Y-Axis Noise Density at 25°C
Figure 12. X-Axis Noise Density at 25°C
Rev. D | Page 7 of 16
140
150
Data Sheet
45
40
40
35
35
30
25
20
15
10
25
20
15
10
SELF-TEST OUTPUT (V)
1.00
0.95
0.90
0.85
0.80
0.75
0.70
Figure 17. Y-Axis Self-Test Response at 25°C
0.90
100
90
0.80
0.75
0.70
0.65
0.60
03757-103
60
50
40
30
20
10
CURRENT (µA)
Figure 18. Supply Current at 25°C
Figure 16. Self-Test Response vs. Temperature
Rev. D | Page 8 of 16
1000
900
800
700
600
500
400
200
0
130
120
110
90
100
TEMPERATURE (°C)
80
70
60
50
40
30
20
0
10
–10
–20
–30
–40
0.50
3V
70
300
0.55
5V
80
03757-018
PERCENT OF POPULATION (%)
0.85
–50
0.65
SELF-TEST OUTPUT (V)
Figure 15. X-Axis Self-Test Response at 25°C
VOLTAGE (1V/g)
0.60
0.50
0.55
0.45
0
0.40
5
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0.60
0.55
0.50
0.40
0
0.45
5
30
03757-019
PERCENT OF POPULATION (%)
45
03757-017
PERCENT OF POPULATION (%)
ADXL103/ADXL203
10
10
0
0
0.387
60
50
40
30
20
Figure 21. X-Axis Sensitivity at 25°C
Rev. D | Page 9 of 16
5
Figure 24. Y-Axis Sensitivity at 25°C
SENSITIVITY (V/g)
2.55
2.54
2.53
2.52
2.51
2.50
2.49
2.48
2.47
2.46
2.45
2.44
TEMPERATURE COEFFICIENT (mg/°C)
03757-020
03757-119
2.57
10
2.56
15
1.2
Figure 22. Y-Axis Zero g Bias at 25°C
1.0
0.8
0.6
0.4
0.2
ZERO g BIAS (V)
03757-022
70
0.387
80
0.377
80
0.367
90
0.357
Figure 20. X-Axis Zero g Bias Temperature Coefficient
0.347
0
0
5
0.337
10
–0.2
15
0.327
20
–0.4
20
–0.6
25
0.317
Figure 19. X-Axis Zero g Bias at 25°C
0.307
0
–0.8
10
0.297
20
2.43
30
–1.0
40
PERCENT OF POPULATION (%)
50
–1.2
25
PERCENT OF POPULATION (%)
03757-117
2.57
2.56
2.55
2.54
2.53
2.52
2.51
2.50
2.49
2.48
2.47
2.46
2.45
2.44
2.43
PERCENT OF POPULATION (%)
60
0.287
70
PERCENT OF POPULATION (%)
TEMPERATURE COEFFICIENT (mg/°C)
03757-118
1.2
1.0
0.8
0.6
0.4
0.2
0
–0.2
–0.4
–0.6
–0.8
–1.0
ZERO g BIAS (V)
03757-021
SENSITIVITY (V/g)
0.377
0.367
0.357
0.347
0.337
0.327
0.317
0.307
0.297
0
–1.2
PERCENT OF POPULATION (%)
0
0.287
PERCENT OF POPULATION (%)
Data Sheet
ADXL103/ADXL203
AD22293
70
60
50
40
30
20
10
Figure 23. Y-Axis Zero g Bias Temperature Coefficient
60
50
40
30
20
ADXL103/ADXL203
Data Sheet
60
50
50
35
30
30
50
03757-108
40
30
TEMPERATURE COEFFICIENT (mg/°C)
03757-009
3.0
2.5
2.0
1.5
1.0
0.5
–3.0
3.5
03757-106
3.0
2.5
1.5
2.0
1.0
0.5
0
–0.5
–1.0
0
–1.5
0
–2.5
5
–2.0
5
0
10
–0.5
10
15
–1.0
15
20
–1.5
20
25
–2.5
25
–2.0
PERCENT OF POPULATION
35
–3.0
Figure 29. Y-Axis Zero g Bias Temperature Coefficient
25
20
20
PERCENT OF POPULATION
25
15
10
5
15
10
5
Rev. D | Page 10 of 16
103
03757-110
SENSITIVITY (mV/g)
Figure 30. Y-Axis Sensitivity at 25°C
Figure 27. X-Axis Sensitivity at 25°C
102
101
100
99
97
103
0
03757-107
SENSITIVITY (mV/g)
102
101
100
99
98
97
0
98
PERCENT OF POPULATION
Figure 28. Y-Axis Zero g Bias Deviation from Ideal at 25°C
Figure 26. X-Axis Zero g Bias Temperature Coefficient
PERCENT OF POPULATION
20
ZERO g BIAS (mV)
Figure 25. X-Axis Zero g Bias Deviation from Ideal at 25°C
TEMPERATURE COEFFICIENT (mg/°C)
10
–50
50
ZERO g BIAS (mV)
03757-105
40
30
20
10
0
–10
0
–20
0
–30
10
–40
10
0
20
–10
20
30
–20
30
40
–30
40
–40
PERCENT OF POPULATION
60
–50
PERCENT OF POPULATION
AD22035 AND AD22037
ADXL103/ADXL203
40
45
35
40
15
90
25°C
80
PERCENT OF POPULATION
100.5
100.0
99.5
99.0
98.5
98.0
105°C
70
60
50
40
30
20
10
Rev. D | Page 11 of 16
960
03757-113
CURRENT (µA)
Figure 34. Supply Current vs. Temperature
Figure 32. Sensitivity vs. Temperature; Parts Soldered to PCB
940
920
900
880
860
840
820
800
780
0
760
125
740
100
720
25
50
75
TEMPERATURE (°C)
700
0
680
–25
03757-112
SENSITIVITY (mV)
0.100
Figure 33. Y-Axis Self Test Response at 25°C
101.0
97.5
–50
0.095
0.060
SELF-TEST OUTPUT (V)
Figure 31. X-Axis Self Test Response at 25°C
03757-114
SELF-TEST OUTPUT (V)
03757-111
0.100
0.095
0.090
0.085
0.080
0
0.075
0
0.070
5
0.065
5
0.090
10
0.085
10
20
0.080
15
25
0.075
20
30
0.070
25
35
0.065
PERCENT OF POPULATION
30
0.060
PERCENT OF POPULATION
Data Sheet
ADXL103/ADXL203
Data Sheet
40
35
35
5.0
4.0
3.0
–5.0
09781-026
PERCENT SENSITIVITY (%)
09781-023
5.0
4.0
3.0
2.0
1.0
–2.0
0
0
–1.0
0
–3.0
5
–4.0
5
2.0
10
1.0
10
15
0
15
20
–1.0
20
25
–2.0
25
30
–3.0
30
–4.0
PERCENT OF POPULATION (%)
40
–5.0
PERCENT OF POPULATION (%)
ALL MODELS
PERCENT SENSITIVITY (%)
Figure 35. Z vs. X Cross-Axis Sensitivity
Figure 37. Z vs. Y Cross-Axis Sensitivity
0.9
0.8
VS = 5V
VOLTAGE (V)
0.6
0.5
VS = 3V
0.3
–50
0
50
TEMPERATURE (°C)
100
150
Figure 36. Supply Current vs. Temperature
09781-027
0.4
09781-024
CURRENT (mA)
0.7
TIME
Figure 38. Turn-On Time; CX, CY = 0.1 μF, Time Scale = 2 ms/DIV
Rev. D | Page 12 of 16
Data Sheet
ADXL103/ADXL203
THEORY OF OPERATION
The ADXL103/ADXL203 are complete acceleration measurement
systems on a single, monolithic IC. The ADXL103 is a singleaxis accelerometer, and the ADXL203 is a dual-axis accelerometer.
Both parts contain a polysilicon surface-micro-machined sensor
and signal conditioning circuitry to implement an open-loop
acceleration measurement architecture. The output signals are
analog voltages that are proportional to acceleration. The
ADXL103/ADXL203 are capable of measuring both positive
and negative accelerations from ±1.7 g to at least ±18 g. The
accelerometer can measure static acceleration forces, such
as gravity, allowing it to be used as a tilt sensor.
The sensor is a surface-micromachined polysilicon structure
built on top of the silicon wafer. Polysilicon springs suspend the
structure over the surface of the wafer and provide a resistance
against acceleration forces. Deflection of the structure is measured
using a differential capacitor that consists of independent fixed
plates and plates attached to the moving mass. The fixed plates
are driven by 180° out-of-phase square waves. Acceleration deflects
the beam and unbalances the differential capacitor, resulting in an
output square wave whose amplitude is proportional to acceleration.
Phase-sensitive demodulation techniques are then used to rectify
the signal and determine the direction of the acceleration.
The output of the demodulator is amplified and brought off-chip
through a 32 kΩ resistor. At this point, the user can set the signal
bandwidth of the device by adding a capacitor. This filtering
improves measurement resolution and helps prevent aliasing.
PERFORMANCE
Rather than using additional temperature compensation circuitry,
innovative design techniques have been used to ensure that
high performance is built in. As a result, there is essentially no
quantization error or nonmonotonic behavior, and temperature
hysteresis is very low (typically less than 10 mg over the −40°C
to +125°C temperature range).
Figure 11 shows the 0 g output performance of eight parts
(x and y axes) over a −40°C to +125°C temperature range.
Figure 13 demonstrates the typical sensitivity shift over
temperature for VS = 5 V. Sensitivity stability is optimized for
VS = 5 V but is still very good over the specified range; it is
typically better than ±1% over temperature at VS = 3 V.
PIN 8
XOUT = –1g
YOUT = 0g
TOP VIEW
(Not to Scale)
PIN 8
XOUT = 0g
YOUT = –1g
XOUT = 0g
YOUT = 0g
PIN 8
XOUT = +1g
YOUT = 0g
EARTH’S SURFACE
Figure 39. Output Response vs. Orientation
Rev. D | Page 13 of 16
03757-028
PIN 8
XOUT = 0g
YOUT = +1g
ADXL103/ADXL203
Data Sheet
APPLICATIONS INFORMATION
POWER SUPPLY DECOUPLING
For most applications, a single 0.1 μF capacitor, CDC, adequately
decouples the accelerometer from noise on the power supply.
However, in some cases, particularly where noise is present at
the 140 kHz internal clock frequency (or any harmonic thereof),
noise on the supply can cause interference on the ADXL103/
ADXL203 output. If additional decoupling is needed, a 100 Ω
(or smaller) resistor or ferrite beads can be inserted in the supply
line of the ADXL103/ADXL203. Additionally, a larger bulk
bypass capacitor (in the 1 μF to 22 μF range) can be added in
parallel to CDC.
SETTING THE BANDWIDTH USING CX AND CY
The ADXL103/ADXL203 has provisions for band limiting the
XOUT and YOUT pins. Capacitors must be added at these pins to
implement low-pass filtering for antialiasing and noise reduction.
The equation for the 3 dB bandwidth is
f–3 dB = 1/(2π(32 kΩ) × C(X, Y))
or more simply,
f–3 dB = 5 μF/C(X, Y)
The tolerance of the internal resistor (RFILT) can vary typically as
much as ±25% of its nominal value (32 kΩ); thus, the bandwidth
varies accordingly. A minimum capacitance of 2000 pF for CX and
CY is required in all cases.
DESIGN TRADE-OFFS FOR SELECTING FILTER
CHARACTERISTICS: THE NOISE/BANDWIDTH
TRADE-OFF
The accelerometer bandwidth selected ultimately determines
the measurement resolution (smallest detectable acceleration).
Filtering can be used to lower the noise floor, improving the
resolution of the accelerometer. Resolution is dependent on
the analog filter bandwidth at XOUT and YOUT.
The output of the ADXL103/ADXL203 has a typical bandwidth
of 2.5 kHz. The user must filter the signal at this point to limit
aliasing errors. The analog bandwidth must be no more than
half the analog-to-digital sampling frequency to minimize
aliasing. The analog bandwidth can be further decreased to
reduce noise and improve resolution.
The ADXL103/ADXL203 noise has the characteristics of white
Gaussian noise, which contributes equally at all frequencies and is
described in terms of μg/√Hz (that is, the noise is proportional to
the square root of the accelerometer bandwidth). Limit bandwidth
to the lowest frequency needed by the application to maximize the
resolution and dynamic range of the accelerometer.
With the single-pole roll-off characteristic, the typical noise of
the ADXL103/ADXL203 is determined by
rmsNoise = (110 μg/√Hz) × ( BW × 1.6 )
At 100 Hz, the noise is
Table 7. Filter Capacitor Selection, CX and CY
Bandwidth (Hz)
1
10
50
100
200
500
rmsNoise = (110 μg/√Hz) × ( 100 × 1.6 ) = 1.4 mg
Capacitor (μF)
4.7
0.47
0.10
0.05
0.027
0.01
Often, the peak value of the noise is desired. Peak-to-peak noise
can only be estimated by statistical methods. Table 8 is useful
for estimating the probabilities of exceeding various peak values,
given the rms value.
Table 8. Estimation of Peak-to-Peak Noise
SELF TEST
The ST pin controls the self test feature. When this pin is set to VS,
an electrostatic force is exerted on the beam of the accelerometer.
The resulting movement of the beam allows the user to test if
the accelerometer is functional. The typical change in output is
750 mg (corresponding to 750 mV). This pin can be left opencircuit or connected to common in normal use.
Never expose the ST pin to voltages greater than VS + 0.3 V. If
the system design is such that this condition cannot be guaranteed
(that is, multiple supply voltages are present), a low VF clamping
diode between ST and VS is recommended.
Peak-to-Peak Value
2 × rms
4 × rms
6 × rms
8 × rms
% of Time That Noise Exceeds
Nominal Peak-to-Peak Value
32
4.6
0.27
0.006
Peak-to-peak noise values give the best estimate of the uncertainty
in a single measurement; peak-to-peak noise is estimated by
6 × rms. Table 9 gives the typical noise output of the ADXL103/
ADXL203 for various CX and CY values.
Table 9. Filter Capacitor Selection (CX, CY)
Bandwidth (Hz)
10
50
100
500
Rev. D | Page 14 of 16
CX, CY
(μF)
0.47
0.1
0.047
0.01
RMS Noise
(mg)
0.4
1.0
1.4
3.1
Peak-to-Peak Noise
Estimate (mg)
2.6
6
8.4
18.7
Data Sheet
ADXL103/ADXL203
USING THE ADXL103/ADXL203 WITH OPERATING
VOLTAGES OTHER THAN 5 V
The ADXL103/ADXL203 is tested and specified at VS = 5 V;
however, it can be powered with VS as low as 3 V or as high
as 6 V. Some performance parameters change as the supply
voltage is varied.
The ADXL103/ADXL203 output is ratiometric, so the output
sensitivity (or scale factor) varies proportionally to the supply
voltage. At VS = 3 V, the output sensitivity is typically 560 mV/g.
The zero g bias output is also ratiometric, so the zero g output is
nominally equal to VS/2 at all supply voltages.
The output noise is not ratiometric but is absolute in volts;
therefore, the noise density decreases as the supply voltage
increases. This is because the scale factor (mV/g) increases
while the noise voltage remains constant. At VS = 3 V, the
noise density is typically 190 μg/√Hz.
USING THE ADXL203 AS A DUAL-AXIS TILT SENSOR
One of the most popular applications of the ADXL203 is tilt
measurement. An accelerometer uses the force of gravity as an
input vector to determine the orientation of an object in space.
An accelerometer is most sensitive to tilt when its sensitive axis
is perpendicular to the force of gravity, that is, parallel to the
earth’s surface. At this orientation, its sensitivity to changes in
tilt is highest. When the accelerometer is oriented on axis to
gravity, that is, near its +1 g or –1 g reading, the change in
output acceleration per degree of tilt is negligible. When the
accelerometer is perpendicular to gravity, its output changes
nearly 17.5 mg per degree of tilt. At 45°, its output changes at
only 12.2 mg per degree, and resolution declines.
Dual-Axis Tilt Sensor: Converting Acceleration to Tilt
Self test response in g is roughly proportional to the square of
the supply voltage. However, when ratiometricity of sensitivity
is factored in with supply voltage, self test response in volts is
roughly proportional to the cube of the supply voltage. So at
VS = 3 V, the self test response is approximately equivalent to
150 mV or equivalent to 270 mg (typical).
The supply current decreases as the supply voltage decreases.
Typical current consumption at VDD = 3 V is 450 μA.
When the accelerometer is oriented so both its x-axis and y-axis
are parallel to the earth’s surface, it can be used as a 2-axis tilt sensor
with a roll axis and a pitch axis. Once the output signal from the
accelerometer has been converted to an acceleration that varies
between –1 g and +1 g, the output tilt in degrees is calculated as
PITCH = ASIN(AX/1 g)
ROLL = ASIN(AY/1 g)
Be sure to account for overranges. It is possible for the
accelerometers to output a signal greater than ±1 g due to
vibration, shock, or other accelerations.
Rev. D | Page 15 of 16
ADXL103/ADXL203
Data Sheet
OUTLINE DIMENSIONS
0.087
0.078
0.069
0.020
0.015
0.010
(R 4 PLCS)
0.028
0.020 DIA
0.012
1
7
0.180
0.177 SQ
0.174
0.106
0.100
0.094
0.075 REF
R 0.008
(8 PLCS)
0.008
0.006
0.004
TOP VIEW
R 0.008
(4 PLCS)
0.054
0.050
0.046
(PLATING OPTION 1,
SEE DETAIL A
FOR OPTION 2)
5
3
BOTTOM VIEW
0.077
0.070
0.063
0.019 SQ
DETAIL A
(OPTION 2)
05-21-2010-D
0.203
0.197 SQ
0.193
0.030
0.025
0.020
Figure 40. 8-Terminal Ceramic Leadless Chip Carrier [LCC]
(E-8-1)
Dimensions shown in inches
ORDERING GUIDE
Model 1, 2
ADXL103CE
ADXL103CE–REEL
ADXL103WCEZB-REEL
AD22035Z
AD22035Z-RL
AD22035Z-RL7
ADW22035Z
ADW22035Z-RL
ADW22035Z-RL7
ADXL203CE
ADXL203CE-REEL
ADXL203WCEZB-REEL
ADXL203EB
AD22293ZA
ADW22293ZA
AD22037Z
AD22037Z-RL
AD22037Z-RL7
ADW22037Z
ADW22037Z-RL
ADW22037Z-RL7
1
2
Axes
1
1
1
1
1
1
1
1
1
2
2
2
Device
Generic
ADXL103
ADXL103
ADXL103
ADXL103
ADXL103
ADXL103
ADXL103
ADXL103
ADXL103
ADXL203
ADXL203
ADXL203
g-Range
±1.7
±1.7
±1.7
±18
±18
±18
±18
±18
±18
±1.7
±1.7
±1.7
Specified
Voltage (V)
5
5
5
5
5
5
5
5
5
5
5
5
Temperature Range
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
–40°C to +125°C
−40°C to +125°C
−40°C to +125°C
2
2
2
2
2
2
2
2
ADXL203
ADXL203
ADXL203
ADXL203
ADXL203
ADXL203
ADXL203
ADXL203
±5
±5
±18
±18
±18
±18
±18
±18
5
5
5
5
5
5
5
5
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
Package Description
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
Evaluation Board
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
8-Terminal Ceramic LCC
Package
Option
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
E-8-1
Z = RoHS Compliant Part.
W = Qualified for Automotive Applications.
AUTOMOTIVE PRODUCTS
The ADXL103W, ADW22035, ADXL203W, ADW22293, and ADW22037 models are available with controlled manufacturing to support
the quality and reliability requirements of automotive applications. Note that these automotive models may have specifications that differ
from the commercial models; therefore, designers should review the Specifications section of this data sheet carefully. Only the automotive grade
products shown are available for use in automotive applications. Contact your local Analog Devices account representative for specific
product ordering information and to obtain the specific Automotive Reliability reports for these models.
©2004–2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D03757-0-9/11(D)
Rev. D | Page 16 of 16
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