Precision ±1.7 g, ±5 g, ±18 g Single-/
Dual-Axis iMEMS® Accelerometer
Data Sheet ADXL103/ADXL203
Rev. D
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Tel: 781.329.4700 www.analog.com
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FEATURES
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
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
GENERAL DESCRIPTION
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.
FUNCTIONAL BLOCK DIAGRAMS
ADXL103
SENSOR
+5V
OUTPUT
AMP
COM ST XOUT
VS
CDC
CX
RFILT
32kΩ
DEMOD
AC
AMP
ADXL203
SENSOR
+5V
OUTPUT
AMP
OUTPUT
AMP
COM ST YOUT
VS
CDC
CY
RFILT
32kΩ
DEMOD
XOUT
CX
RFILT
32kΩ
AC
AMP
03757-001
Figure 1.
ADXL103/ADXL203 Data Sheet
Rev. D | Page 2 of 16
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications....................................................................................... 1
General Description......................................................................... 1
Functional Block Diagrams............................................................. 1
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 4
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
Theory of Operation ...................................................................... 13
Performance................................................................................ 13
Applications Information.............................................................. 14
Power Supply Decoupling......................................................... 14
Setting the Bandwidth Using CX and CY................................. 14
Self Test........................................................................................ 14
Design Trade-Offs for Selecting Filter Characteristics: The
Noise/Bandwidth Trade-Off ..................................................... 14
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
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
5/10—Rev. B to Rev. C
Changes to Figure 24 Caption....................................................... 12
Added Automotive Products Section .......................................... 12
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
Data Sheet ADXL103/ADXL203
Rev. D | Page 3 of 16
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.
ADXL103/ADXL203 AD22293 AD22035/AD22037
Parameter Test Conditions Min Typ Max Min Typ Max Min Typ Max Unit
SENSOR Each axis
Measurement Range1 ±1.7 ±5 ±6 ±18 g
Nonlinearity % of full scale ±0.2 ±1.25 ±0.2 ±1.25 ±0.2 ±1.25 %
Package Alignment Error ±1 ±1 ±1 Degrees
Alignment Error (ADXL203) X to Y sensor ±0.1 ±0.1 ±0.1 Degrees
Cross-Axis Sensitivity ±1.5 ±3 ±1.5 ±3 ±1.5 ±3 %
SENSITIVITY (RATIOMETRIC)2 Each axis
Sensitivity at XOUT, YOUT V
S = 5 V 960 1000 1040 293 312 331 94 100 106 mV/g
Sensitivity Change Due to
Temperature3
VS = 5 V ±0.3 ±0.3 ±0.3 %
ZERO g BIAS LEVEL (RATIOMETRIC) Each axis
0 g Voltage at XOUT, YOUT V
S = 5 V 2.4 2.5 2.6 2.4 2.5 2.6 2.4 2.5 2.6 V
Initial 0 g Output Deviation
From Ideal
VS = 5 V, 25°C ±25 ±50 ±125 mg
0 g Offset vs. Temperature ±0.1 ±0.8 ±0.3 ±1.8 ±1 mg/°C
NOISE
Output Noise <4 kHz, VS = 5 V 1 3 1 3 2 mV rms
Noise Density 110 200 130 μg/√Hz
rms
FREQUENCY RESPONSE4
CX, CY Range5 0.002 10 0.002 10 0.002 10 μF
RFILT Tolerance 24 32 40 24 32 40 24 32 40 kΩ
Sensor Resonant Frequency 5.5 5.5 5.5 kHz
SELF TEST6
Logic Input Low 1 1 1 V
Logic Input High 4 4 4 V
ST Input Resistance to GND 30 50 30 50 30 50 kΩ
Output Change at XOUT, YOUT ST 0 to ST 1 450 750 1100 125 250 375 60 80 100 mV
OUTPUT AMPLIFIER
Output Swing Low No load 0.05 0.2 0.05 0.2 0.05 0.2 V
Output Swing High No load 4.5 4.8 4.5 4.8 4.5 4.8 V
POWER SUPPLY (VDD)
Operating Voltage Range 3 6 3 6 3 6 V
Quiescent Supply Current 0.7 1.1 0.7 1.1 0.7 1.1 mA
Turn-On Time7 20 20 20 ms
1 Guaranteed by measurement of initial offset and sensitivity.
2 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.
ADXL103/ADXL203 Data Sheet
Rev. D | Page 4 of 16
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter Rating
Acceleration (Any Axis, Unpowered) 3500 g
Acceleration (Any Axis, Powered) 3500 g
Drop Test (Concrete Surface) 1.2 m
VS −0.3 V to +7.0 V
All Other Pins (COM − 0.3 V) to
(VS + 0.3 V)
Output Short-Circuit Duration
(Any Pin to Common)
Indefinite
Temperature Range (Powered) −55°C to +125°C
Temperature Range (Storage) −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.
Table 3. Package Characteristics
Package Type θJA θ
JC Device Weight
8-Terminal Ceramic LCC 120°C/W 20°C/W <1.0 gram
ESD CAUTION
tP
tL
t
25°C TO PEAK
tS
PREHEAT
CRITICAL ZONE
T
L
TO T
P
TEMPERATURE
TIME
RAMP-DOWN
RAMP-UP
T
SMIN
T
SMAX
T
P
T
L
03757-102
Figure 2. Recommended Soldering Profile
Table 4. Solder Profile Parameters
Test Condition
Profile Feature Sn63/Pb37 Pb-Free
Average Ramp Rate (TL to TP) 3°C/second maximum 3°C/second maximum
Preheat
Minimum Temperature (TSMIN) 100°C 150°C
Maximum Temperature (TSMAX) 150°C 200°C
Time (TSMIN to TSMAX) (tS) 60 seconds to 120 seconds 60 seconds to 150 seconds
TSMAX to TL
Ramp-Up Rate 3°C/second 3°C/second
Time Maintained above Liquidous (TL)
Liquidous Temperature (TL) 183°C 217°C
Time (tL) 60 seconds to 150 seconds 60 seconds to 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 seconds to 30 seconds 20 seconds to 40 seconds
Ramp-Down Rate 6°C/second maximum 6°C/second maximum
Time 25°C to Peak Temperature 6 minutes maximum 8 minutes maximum
Data Sheet ADXL103/ADXL203
Rev. D | Page 5 of 16
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
ADXL103
TOP VIEW
(Not to Scale)
ST
1
NC
2
COM
3
NC
4
X
OUT
NC
NC
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN
.
7
6
5
V
S
+X
8
03757-002
Figure 3. ADXL103 Pin Configuration
ADXL203
TOP VIEW
(Not to Scale)
ST
1
NC
2
COM
3
NC
4
X
OUT
Y
OUT
NC
7
6
5
V
S
8
+X
+Y
03757-003
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN
.
Figure 4. ADXL203 Pin Configuration
Table 5. ADXL103 Pin Function Descriptions
Pin No. Mnemonic Description
1 ST Self Test
2 NC Do Not Connect
3 COM Common
4 NC Do Not Connect
5 NC Do Not Connect
6 NC Do Not Connect
7 XOUT X Channel Output
8 VS 3 V to 6 V
Table 6. ADXL203 Pin Function Descriptions
Pin No. Mnemonic Description
1 ST Self Test
2 NC Do Not Connect
3 COM Common
4 NC Do Not Connect
5 NC Do Not Connect
6 YOUT Y Channel Output
7 XOUT X Channel Output
8 VS 3 V to 6 V
ADXL103/ADXL203 Data Sheet
Rev. D | Page 6 of 16
TYPICAL PERFORMANCE CHARACTERISTICS
ADXL103 AND ADXL203
VS = 5 V for all graphs, unless otherwise noted.
PERCENT OF POPULATION (%)
0
25
20
15
10
5
ZERO g BIAS (V)
–0.10
–0.08
–0.06
–0.04
–0.02
0
0.02
0.04
0.06
0.08
0.10
03757-010
Figure 5. X-Axis Zero g Bias Deviation from Ideal at 25°C
PERCENT OF POPULATION (%)
0
25
30
20
15
10
5
TEMPERATURE COEFFICIENT (mg/°C)
–0.80
–0.70
–0.60
–0.50
–0.40
–0.30
–0.20
–0.10
0
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
03757-011
Figure 6. X-Axis Zero g Bias Temperature Coefficient
PERCENT OF POPULATION (%)
0
35
40
20
25
30
15
10
5
SENSITIVITY (V/g)
0.94
0.95
0.96
0.97
0.98
0.99
1.00
1.01
1.02
1.03
1.04
1.05
1.06
03757-012
Figure 7. X-Axis Sensitivity at 25°C
PERCENT OF POPULATION (%)
0
30
25
20
15
10
5
–0.10
–0.08
–0.06
–0.04
–0.02
0
0.02
0.04
0.06
0.08
0.10
03757-013
ZERO g BIAS (V)
Figure 8. Y-Axis Zero g Bias Deviation from Ideal at 25°C
PERCENT OF POPUL
A
TION (%)
0
25
20
15
10
5
–0.80
–0.70
–0.60
–0.50
–0.40
–0.30
–0.20
–0.10
0
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
03757-014
TEMPERATURE COEFFICIENT (mg/°C)
Figure 9. Y-Axis Zero g Bias Temperature Coefficient
PERCENT OF POPULATION (%)
0
35
40
20
25
30
15
10
5
SENSITIVITY (V/g)
0.94
0.95
0.96
0.97
0.98
0.99
1.00
1.01
1.02
1.03
1.04
1.05
1.06
03757-015
Figure 10. Y-Axis Sensitivity at 25°C
Data Sheet ADXL103/ADXL203
Rev. D | Page 7 of 16
TEMPERATURE (°C)
VOLTAGE (1V/g)
–50
2.40
2.60
2.58
2.56
2.54
2.52
2.50
2.48
2.46
2.44
2.42
–40
–30
–20
–10
0
10
20
30
50
40
60
70
80
90
100
110
120
130
03757-004
Figure 11. Zero g Bias vs. Temperature; Parts Soldered to PCB
X AXIS NOISE DENSITY (mg/√Hz)
PERCENT OF POPULATION (%)
0
40
35
30
25
20
15
10
5
45
50
15014013012011010090807060
03757-007
Figure 12. X-Axis Noise Density at 25°C
TEMPERATURE (°C)
SENSITIVITY (V/
g
)
–50
0.97
1.00
0.99
0.98
1.02
1.01
1.03
–40
–30
–20
–10
0
10
20
30
50
40
60
70
80
90
100
110
120
130
03757-016
Figure 13. Sensitivity vs. Temperature; Parts Soldered to PCB
Y AXIS NOISE DENSITY (mg/√Hz)
PERCENT OF POPULATION (%)
0
40
35
30
25
20
15
10
5
45
50
15014013012011010090807060
03757-008
Figure 14. Y-Axis Noise Density at 25°C
ADXL103/ADXL203 Data Sheet
Rev. D | Page 8 of 16
PERCENT OF POPULATION (%)
0
45
20
25
30
35
40
15
10
5
SELF-TEST OUTPUT (V)
0.40
0.45
0.50
0.55
0.65
0.60
0.70
0.75
0.80
0.85
0.90
0.95
1.00
03757-017
Figure 15. X-Axis Self-Test Response at 25°C
TEMPERATURE (°C)
VOLTAGE (1V/
g
)
–50
0.50
0.80
0.75
0.70
0.65
0.60
0.55
0.85
0.90
–40
–30
–20
–10
0
10
20
30
50
40
60
70
80
90
100
110
120
130
03757-103
Figure 16. Self-Test Response vs. Temperature
PERCENT OF POPULATION (%)
0
45
20
25
30
35
40
15
10
5
SELF-TEST OUTPUT (V)
0.40
0.45
0.50
0.55
0.65
0.60
0.70
0.75
0.80
0.85
0.90
0.95
1.00
03757-019
Figure 17. Y-Axis Self-Test Response at 25°C
PERCENT OF POPULATION (%)
0
80
70
60
50
40
30
20
10
90
100
CURRENT (µA)
3V
5V
200
300
400
500
600
700
800
900
1000
03757-018
Figure 18. Supply Current at 25°C
Data Sheet ADXL103/ADXL203
Rev. D | Page 9 of 16
AD22293
0
10
20
30
40
50
60
2.43
2.44
2.45
2.46
2.47
2.48
2.49
2.50
2.51
2.52
2.53
2.54
2.55
2.56
2.57
ZERO g BIAS (V)
PERCENT OF POPUL
A
TION (%)
03757-117
Figure 19. X-Axis Zero g Bias at 25°C
PERCENT OF POPUL
A
TION (%)
0
5
10
15
20
25
–1.2
–1.0
–0.8
–0.6
–0.4
–0.2
0
0.2
0.4
0.6
0.8
1.0
1.2
TEMPERATURE COEFFICIENT (mg/°C)
03757-118
Figure 20. X-Axis Zero g Bias Temperature Coefficient
PERCENT OF POPUL
A
TION (%)
0
10
20
30
40
50
60
70
80
90
0.287
0.297
0.307
0.317
0.327
0.337
0.347
0.357
0.367
0.377
0.387
SENSITIVITY (V/g)
03757-021
Figure 21. X-Axis Sensitivity at 25°C
PERCENT OF POPUL
A
TION (%)
0
10
20
30
40
50
60
70
2.43
2.44
2.45
2.46
2.47
2.48
2.49
2.50
2.51
2.52
2.53
2.54
2.55
2.56
2.57
ZERO g BIAS (V)
03757-119
Figure 22. Y-Axis Zero g Bias at 25°C
PERCENT OF POPUL
A
TION (%)
–1.2
–1.0
–0.8
–0.6
–0.4
–0.2
0
0.2
0.4
0.6
0.8
1.0
1.2
TEMPERATURE COEFFICIENT (mg/°C)
0
5
10
15
20
25
03757-020
Figure 23. Y-Axis Zero g Bias Temperature Coefficient
PERCENT OF POPUL
A
TION (%)
0
10
20
30
40
50
60
70
80
0.287
0.297
0.307
0.317
0.327
0.337
0.347
0.357
0.367
0.377
0.387
SENSITIVITY (V/g)
03757-022
Figure 24. Y-Axis Sensitivity at 25°C
ADXL103/ADXL203 Data Sheet
Rev. D | Page 10 of 16
AD22035 AND AD22037
0
10
20
30
40
50
60
–50
–40
–30
–20
–10
0
10
20
30
40
50
PERCENT OF POPUL
A
TION
ZERO g BIAS (mV)
03757-105
Figure 25. X-Axis Zero g Bias Deviation from Ideal at 25°C
0
5
10
15
20
25
30
35
–3.0
–2.5
–2.0
–1.5
–1.0
–0.5
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
PERCENT OF POPUL
A
TION
TEMPERATURE COEFFICIENT (mg/°C)
03757-106
Figure 26. X-Axis Zero g Bias Temperature Coefficient
0
5
10
15
20
25
97
98
99
100
101
102
103
PERCENT OF POPUL
A
TION
SENSITIVITY (mV/g)
03757-107
Figure 27. X-Axis Sensitivity at 25°C
0
10
20
30
40
50
60
–50
–40
–30
–20
–10
0
10
20
30
40
50
PERCENT OF POPUL
A
TION
03757-108
ZERO g BIAS (mV)
Figure 28. Y-Axis Zero g Bias Deviation from Ideal at 25°C
0
5
10
15
20
25
30
35
–3.0
–2.5
–2.0
–1.5
–1.0
–0.5
0
0.5
1.0
1.5
2.0
2.5
3.0
PERCENT OF POPUL
A
TION
TEMPERATURE COEFFICIENT (mg/°C)
03757-009
Figure 29. Y-Axis Zero g Bias Temperature Coefficient
0
5
10
15
20
25
97
98
99
100
101
102
103
PERCENT OF POPUL
A
TION
SENSITIVITY (mV/g)
03757-110
Figure 30. Y-Axis Sensitivity at 25°C
Data Sheet ADXL103/ADXL203
Rev. D | Page 11 of 16
0
5
10
15
20
25
30
35
40
0.060
0.065
0.070
0.075
0.080
0.085
0.090
0.095
0.100
PERCENT OF POPUL
TION
SELF-TEST OUTPUT (V)
03757-111
Figure 31. X-Axis Self Test Response at 25°C
97.5
98.0
98.5
99.0
99.5
100.0
100.5
101.0
–50 –25 0 25 50 75 100 125
SENSITIVITY (mV)
TEMPERATURE (°C)
03757-112
Figure 32. Sensitivity vs. Temperature; Parts Soldered to PCB
0
5
10
15
20
25
30
35
40
45
0.060
0.065
0.070
0.075
0.080
0.085
0.090
0.095
0.100
PERCENT OF POPUL
A
TION
SELF-TEST OUTPUT (V)
03757-114
Figure 33. Y-Axis Self Test Response at 25°C
0
10
20
30
40
50
60
70
80
90
680
700
720
740
760
780
800
820
840
860
880
900
920
940
960
PERCENT OF POPUL
TION
CURRENT (µA)
25°C 105°C
03757-113
Figure 34. Supply Current vs. Temperature
ADXL103/ADXL203 Data Sheet
Rev. D | Page 12 of 16
ALL MODELS
PERCENT SENSITIVITY (%)
PERCENT OF POPULATION (
%
)
–5.0
0
30
25
20
15
10
5
35
40
–4.0
–3.0
–2.0
–1.0
0
1.0
2.0
3.0
4.0
5.0
09781-023
Figure 35. Z vs. X Cross-Axis Sensitivity
TEMPERATURE (°C)
CURRENT (
m
A)
0.3
0.8
0.7
0.6
0.5
0.4
0.9
150100500–50
V
S
=5V
V
S
=3V
09781-024
Figure 36. Supply Current vs. Temperature
PERCENT SENSITIVITY (%)
PERCENT OF POPULATION (
%
)
–5.0
0
30
25
20
15
10
5
35
40
–4.0
–3.0
–2.0
–1.0
0
1.0
2.0
3.0
4.0
5.0
09781-026
Figure 37. Z vs. Y Cross-Axis Sensitivity
09781-027
TIME
VOLTAGE (V)
Figure 38. Turn-On Time; CX, CY = 0.1 μF, Time Scale = 2 ms/DIV
Data Sheet ADXL103/ADXL203
Rev. D | Page 13 of 16
THEORY OF OPERATION
The ADXL103/ADXL203 are complete acceleration measurement
systems on a single, monolithic IC. The ADXL103 is a single-
axis 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.
EARTH’S SURFACE
TOP VIEW
(Not to Scale)
X
OUT
= 0g
Y
OUT
= 0g
PIN 8
X
OUT
= –1g
Y
OUT
= 0g
PIN 8
X
OUT
= +1g
Y
OUT
= 0g
PIN 8
X
OUT
= 0g
Y
OUT
= +1g
PIN 8
X
OUT
= 0g
Y
OUT
= –1g
03757-028
Figure 39. Output Response vs. Orientation
ADXL103/ADXL203 Data Sheet
Rev. D | Page 14 of 16
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.
Table 7. Filter Capacitor Selection, CX and CY
Bandwidth (Hz) Capacitor (μF)
1 4.7
10 0.47
50 0.10
100 0.05
200 0.027
500 0.01
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 open-
circuit 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.
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) × ( 6.1BW ×)
At 100 Hz, the noise is
rmsNoise = (110 μg/√Hz) × ( 6.1100×) = 1.4 mg
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
Peak-to-Peak Value
% of Time That Noise Exceeds
Nominal Peak-to-Peak Value
2 × rms 32
4 × rms 4.6
6 × rms 0.27
8 × rms 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)
CX, CY
(μF)
RMS Noise
(mg)
Peak-to-Peak Noise
Estimate (mg)
10 0.47 0.4 2.6
50 0.1 1.0 6
100 0.047 1.4 8.4
500 0.01 3.1 18.7
Data Sheet ADXL103/ADXL203
Rev. D | Page 15 of 16
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.
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.
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
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.
ADXL103/ADXL203 Data Sheet
Rev. D | Page 16 of 16
OUTLINE DIMENSIONS
BOTTOM VIEW
(PLATING OPTION 1,
SEE DETAIL A
FOROPTION2)
DETAIL A
(OPTION 2)
1
3
5
7
TOP VIEW
0.075 REF
R 0.008
(4 PLCS)
0.203
0.197 SQ
0.193
0.020
0.015
0.010
(R 4 PLCS)
0.180
0.177 SQ
0.174
0.087
0.078
0.069
0.008
0.006
0.004 0.077
0.070
0.063
0.054
0.050
0.046
0.030
0.025
0.020 0.028
0.020 DIA
0.012
0.019 SQ
0.106
0.100
0.094
R 0.008
(8 PLCS)
05-21-2010-D
Figure 40. 8-Terminal Ceramic Leadless Chip Carrier [LCC]
(E-8-1)
Dimensions shown in inches
ORDERING GUIDE
Model1, 2 Axes
Device
Generic g-Range
Specified
Voltage (V) Temperature Range Package Description
Package
Option
ADXL103CE 1 ADXL103 ±1.7 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADXL103CE–REEL 1 ADXL103 ±1.7 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADXL103WCEZB-REEL 1 ADXL103 ±1.7 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
AD22035Z 1 ADXL103 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
AD22035Z-RL 1 ADXL103 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
AD22035Z-RL7 1 ADXL103 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADW22035Z 1 ADXL103 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADW22035Z-RL 1 ADXL103 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADW22035Z-RL7 1 ADXL103 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADXL203CE 2 ADXL203 ±1.7 5 –40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADXL203CE-REEL 2 ADXL203 ±1.7 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADXL203WCEZB-REEL 2 ADXL203 ±1.7 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADXL203EB Evaluation Board
AD22293ZA 2 ADXL203 ±5 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADW22293ZA 2 ADXL203 ±5 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
AD22037Z 2 ADXL203 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
AD22037Z-RL 2 ADXL203 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
AD22037Z-RL7 2 ADXL203 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADW22037Z 2 ADXL203 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADW22037Z-RL 2 ADXL203 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
ADW22037Z-RL7 2 ADXL203 ±18 5 −40°C to +125°C 8-Terminal Ceramic LCC E-8-1
1 Z = RoHS Compliant Part.
2 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)