Precision ±1.7 g Single-/Dual-Axis
i MEMS® Accelerometer
ADXL204
Rev. A
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Fax: 781.461.3113 ©2006 Analog Devices, Inc. All rights reserved.
FEATURES
High performance, dual-axis accelerometer on a
single IC chip
Specified at VS = 3.3 V
5 mm × 5 mm × 2 mm LCC package
Better than 2 mg resolution at 60 Hz
Low power: 500 μA at VS = 3.3 V (typical)
High zero g bias stability
High sensitivity accuracy
–40°C to +125°C temperature range
X-axis and Y-axis aligned to within 0.1° (typical)
BW adjustment with a single capacitor
Single-supply operation
3500 g shock survival
RoHS compliant
Compatible with Sn/Pb- and Pb-free solder processes
APPLICATIONS
Vehicle dynamic control (VDC)/electronic stability program
(ESP) systems
Electronic chassis controls
Electronic braking
Platform stabilization/leveling
Navigation
Alarms and motion detectors
High accuracy, 2-axis tilt sensing
GENERAL DESCRIPTION
The ADXL204 is a high precision, low power, complete dual-
axis accelerometer with signal-conditioned voltage outputs, all
on a single monolithic IC. Like the ADXL203, it measures
acceleration with a full-scale range of ±1.7 g; however, the
ADXL204 is tested and specified for 3.3 V supply voltage,
whereas the ADXL203 is tested and specified at 5 V. Both parts
function well over a wide 3 V to 6 V operating voltage range.
The ADXL204 can measure both dynamic acceleration (for
example, vibration) and static acceleration (for example, gravity).
The typical noise floor is 170 μg/√Hz, allowing signals below
2 mg (0.1° 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 ADXL204 is available in a 5 mm × 5 mm × 2 mm,
8-terminal hermetic LCC package.
FUNCTIONAL BLOCK DIAGRAM
ADXL204
SENSOR
+5
V
OUTPUT
AMP
OUTPUT
AMP
COM ST Y
OUT
V
S
C
DC
C
Y
R
FILT
32kΩ
DEMOD
X
OUT
C
X
R
FILT
32kΩ
AC
AMP
05512-001
Figure 1.
ADXL204
Rev. A | Page 2 of 12
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications....................................................................................... 1
General Description......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 4
ESD Caution.................................................................................. 4
Pin Configuration and Function Descriptions............................. 5
Typical Performance Characteristics ............................................. 6
Theory of Operation ........................................................................ 9
Performance .................................................................................. 9
Applications..................................................................................... 10
Power Supply Decoupling ......................................................... 10
Setting the Bandwidth Using CX and CY................................. 10
Self Test........................................................................................ 10
Design Trade-Offs for Selecting Filter Characteristics: The
Noise/BW Trade-Off.................................................................. 10
Using the ADXL204 with Operating Voltages
Other than 3.3 V .......................................................................... 11
Using the ADXL204 as a Dual-Axis Tilt Sensor ........................ 11
Outline Dimensions....................................................................... 12
Ordering Guide .......................................................................... 12
REVISION HISTORY
3/06—Rev. 0 to Rev. A
Changes to Format .............................................................Universal
Changes to Product Title, Features, and General Description... 1
Changes to Table 1............................................................................ 3
Changes to Table 2............................................................................ 4
Added Figure 2 and Table 4............................................................. 4
Changes to Figure 3.......................................................................... 5
Changes to Figure 11 and Figure 14............................................... 7
Changes to Table 7.......................................................................... 10
4/05—Revision 0: Initial Version
ADXL204
Rev. A | Page 3 of 12
SPECIFICATIONS
All minimum and maximum specifications are guaranteed. Typical specifications are not guaranteed.
TA = –40°C to +125°C; VS = 3.3 V; CX = CY = 0.1 μF; acceleration = 0 g, unless otherwise noted.
Table 1.
Parameter Conditions Min Typ Max Unit
SENSOR INPUT Each axis
Measurement Range1 ±1.7
g
Nonlinearity % of full scale ±0.2 ±1.25 %
Package Alignment Error ±1 Degrees
Alignment Error X sensor to Y sensor ±0.1 Degrees
Cross Axis Sensitivity ±1.5 ±3 %
SENSITIVITY (RATIOMETRIC)2Each axis
Sensitivity at XOUT, YOUT VS = 3.3 V 595 620 645 mV/g
Sensitivity Change due to Temperature3VS = 3.3 V ±0.3 %
ZERO g BIAS LEVEL (RATIOMETRIC) Each axis
0 g Voltage at XOUT, YOUT VS = 3.3 V 1.55 1.65 1.75 V
Initial 0 g Output Deviation from Ideal VS = 3.3 V, 25°C ±50 mg
0 g Offset vs. Temperature ±0.15 ±0.8 mg/°C
NOISE PERFORMANCE
Output Noise <4 kHz, VS = 3.3 V 1 3 mV rms
Noise Density 170 μg/√Hz rms
FREQUENCY RESPONSE4
CX, CY Range5 0.002 10 μF
RFILT Tolerance 24 32 40 kΩ
Sensor Resonant Frequency 5.5 kHz
SELF TESTT
6
Logic Input Low 0.66 V
Logic Input High 2.64 V
ST Input Resistance to Ground 30 50 kΩ
Output Change at XOUT, YOUT Self test 0 to 1 100 200 300 mV
OUTPUT AMPLIFIER
Output Swing Low No load 0.05 0.2 V
Output Swing High No load 2.9 3.1 V
POWER SUPPLY
Operating Voltage Range 3 6 V
Quiescent Supply Current 0.5 0.9 mA
Turn-On Time7 20 ms
1 Guaranteed by measurement of initial offset and sensitivity.
2 Sensitivity is essentially ratiometric to VS. For VS = 3.0 V to 3.6 V, sensitivity is typically 185 mV/V/g to 190 mV/V/g.
3 Defined as the 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.
ADXL204
Rev. A | Page 4 of 12
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 θJC Device Weight
8-Terminal LCC 120°C/W 20°C/W <1.0 gram
05512-002
t
P
t
L
t
25°C TO PEAK
t
S
PREHEAT
CRITICAL ZONE
T
L
TO T
P
TEMPERATURE
TIME
RAMP-DOWN
RAMP-UP
T
SMIN
T
SMAX
T
P
T
L
Figure 2. Recommended Soldering Profile
Table 4.
Condition
Profile Feature Sn63/Pb37 Pb-Free
AVERAGE RAMP RATE (TL TO TP) 3°C/sec maximum 3°C/sec maximum
PREHEAT
Minimum Temperature (TSMIN) 100°C 150°C
Minimum Temperature (TSMAX) 150°C 200°C
Time (TSMIN to TSMAX) (tS) 60 sec to 120 sec 60 sec to 150 sec
TSMAX TO TL
Ramp-Up Rate 3°C/sec 3°C/sec
TIME MAINTAINED ABOVE LIQUIDOUS (TL)
Liquidous Temperature (TL) 183°C 217°C
Time (tL) 60 sec to 150 sec 60 sec to 150 sec
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 sec to 30 sec 20 sec to 40 sec
RAMP-DOWN RATE 6°C/sec maximum 6°C/sec maximum
TIME 25°C TO PEAK TEMPERATURE 6 minutes maximum 8 minutes maximum
ESD CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the
human body and test equipment and can discharge without detection. Although this product features
proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy
electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance
degradation or loss of functionality.
ADXL204
Rev. A | Page 5 of 12
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
A
DXL204E
TOP VIEW
(Not to Scale)
ST 1
DNC 2
COM 3
DNC
4
XOUT
YOUT
DNC
7
6
5
VS
+Y
+X
8
05512-022
Figure 3. Pin Configuration
Table 5. Pin Function Descriptions
Pin No. Mnemonic Description
1 ST Self Test
2 DNC Do Not Connect
3 COM Common
4 DNC Do Not Connect
5 DNC Do Not Connect
6 YOUT Y Channel Output
7 XOUT X Channel Output
8 VS3 V to 6 V
ADXL204
Rev. A | Page 6 of 12
TYPICAL PERFORMANCE CHARACTERISTICS
VS = 3.3 V for all graphs, unless otherwise noted.
0
35
20
25
30
15
10
5
05512-003
1.551
1.573
1.595
1.617
1.639
1.661
1.683
1.705
1.727
1.749
VOLTS (V)
PERCENT OF POPULATION (%)
Figure 4. X-Axis Zero g Bias Output at 25°C
0
25
20
15
10
5
05512-004
–0.8
–0.7
–0.6
–0.5
–0.4
–0.3
–0.2
–0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
mg/°C
PERCENT OF POPULATION (%)
Figure 5. X-Axis Zero g Bias Temperature Coefficient
0
60
40
50
30
20
10
05512-005
0.577
0.655
0.649
0.644
0.638
0.633
0.627
0.621
0.616
0.610
0.605
0.599
0.594
0.588
0.583
V/g
PERCENT OF POPULATION (%)
Figure 6. X-Axis Sensitivity at 25°C
0
35
20
25
30
15
10
5
05512-006
1.551
1.573
1.595
1.617
1.639
1.661
1.683
1.705
1.727
1.749
VOLTS (V)
PERCENT OF POPULATION (%)
Figure 7. Y-Axis Zero g Bias Output at 25°C
0
25
20
15
10
5
05512-007
–0.8
–0.7
–0.6
–0.5
–0.4
–0.3
–0.2
–0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
mg/°C
PERCENT OF POPULATION (%)
Figure 8. Y-Axis Zero g Bias Temperature Coefficient
0
70
60
40
50
30
20
10
05512-008
0.577
0.655
0.649
0.644
0.638
0.633
0.627
0.621
0.616
0.610
0.605
0.599
0.594
0.588
0.583
V/g
PERCENT OF POPULATION (%)
Figure 9. Y-Axis Sensitivity at 25°C
ADXL204
Rev. A | Page 7 of 12
TEMPERATURE (°C)
VOLTAGE (1V/g)
–50
1.590
1.710
1.698
1.686
1.674
1.662
1.650
1.638
1.626
1.614
1.602
–40
–30
–20
–10
0
10
20
30
50
40
60
70
80
90
100
110
120
130
05512-009
Figure 10. Zero g Bias vs. Temperature—Parts Soldered to PCB
0
45
40
34
30
25
20
15
10
5
05512-010
120 130 140 150 160 170 180 190 200 210
µg/ Hz
PERCENT OF POPULATION (%)
Figure 11. X-Axis Noise Density at 25°C
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
05512-011
Figure 12. Z vs. X Cross-Axis Sensitivity
TEMPERATURE (°C)
SENSITIVITY (V/
g
)
–50
0.58
0.62
0.61
0.60
0.64
0.63
0.65
–40
–30
–20
–10
0
10
20
30
50
40
60
70
80
90
100
110
120
130
05512-012
Figure 13. Sensitivity vs. Temperature—Parts Soldered to PCB
0
50
45
40
34
30
25
20
15
10
5
05512-013
120 130 140 150 160 170 180 190 200 210
µg/ Hz
PERCENT OF POPULATION (%)
Figure 14. Y-Axis Noise Density at 25°C
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
05512-014
Figure 15. Z vs. Y Cross-Axis Sensitivity
ADXL204
Rev. A | Page 8 of 12
TEMPERATURE (°C)
CURRENT (mA)
0.3
0.8
0.7
0.6
0.5
0.4
0.9
05512-015
150100500–50
V
S
= 5V
V
S
= 3V
Figure 16. Supply Current vs. Temperature
0
35
25
30
20
15
10
5
05512-016
0.135
0.269
0.256
0.242
0.229
0.216
0.202
0.189
0.175
0.162
0.148
VOLTS (V)
PERCENT OF POPULATION (%)
Figure 17. X-Axis Self-Test Response at 25°C
TEMPERATURE (°C)
VOLTAGE (1V/
g
)
–50
0.08
0.26
0.23
0.20
0.17
0.14
0.11
0.29
0.32
–40
–30
–20
–10
0
10
20
30
50
40
60
70
80
90
100
110
120
130
05512-017
Figure 18. Self-Test Response vs. Temperature
PERCENT OF POPULATION (%)
0
80
70
60
50
40
30
20
10
90
100
05512-018
(µA)
3V
5V
200
300
400
500
600
700
800
900
1000
Figure 19. Supply Current at 25°C
0
30
25
20
15
10
5
05512-019
0.135
0.269
0.256
0.242
0.229
0.216
0.202
0.189
0.175
0.162
0.148
VOLTS (V)
PERCENT OF POPULATION (%)
Figure 20. Y-Axis Self-Test Response at 25°C
05512-020
Figure 21. Turn-On Time—CX, CY = 0.1 μF, Time Scale = 2 ms/DIV
ADXL204
Rev. A | Page 9 of 12
THEORY OF OPERATION
EARTH'S SURFACE
05512-021
TOP VIEW
(Not to Scale)
PIN 8
X
OUT
= 1.65V
Y
OUT
= 1.03V
X
OUT
= 1.65V
Y
OUT
= 1.65V
PIN 8
X
OUT
= 1.65V
Y
OUT
= 2.27V
PIN 8
X
OUT
= 1.03V
Y
OUT
= 1.65V
PIN 8
X
OUT
= 2.27V
Y
OUT
= 1.65V
Figure 22. Output Response vs. Orientation
The ADXL204 is a complete acceleration measurement system on
a single monolithic IC. The ADXL204 is a dual-axis accelerometer.
It contains a polysilicon surface-micromachined sensor and
signal conditioning circuitry to implement an open-loop
acceleration measurement architecture. The output signals are
analog voltages proportional to acceleration. The ADXL204 is
capable of measuring both positive and negative accelerations to
at least ±1.7 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
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 10 shows the zero g output performance of eight parts
(X-axis and Y-axis) over a –40°C to +125°C temperature range.
Figure 13 demonstrates the typical sensitivity shift over tem-
perature for VS = 3.3 V. Sensitivity stability is typically better
than ±1% over temperature.
ADXL204
Rev. A | Page 10 of 12
APPLICATIONS
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 ADXL204
output. If additional decoupling is needed, a 100 Ω, or smaller,
resistor or ferrite bead can be inserted in the supply line of the
ADXL204. 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 ADXL204 has provisions for bandlimiting 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 band-
width varies accordingly. A minimum capacitance of 2000 pF
for CX and CY is required in all cases.
Table 6. 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 accelero-
meter. The resulting movement of the beam allows the user to
test if the accelerometer is functional. The typical change in
output is 325 mg (corresponding to 200 mV). This pin can be
left open-circuit or connected to common in normal use.
The ST pin should never be exposed to voltage greater than
VS + 0.3 V. If the system design is such that this condition
cannot be guaranteed (that is, multiple supply voltages present),
a low VF clamping diode between ST and VS is recommended.
DESIGN TRADE-OFFS FOR SELECTING FILTER
CHARACTERISTICS: THE NOISE/BW TRADE-OFF
The accelerometer bandwidth selected ultimately determines
the measurement resolution (smallest detectable acceleration).
Filtering can be used to lower the noise floor, which improves
the resolution of the accelerometer. Resolution is dependent on
the analog filter bandwidth at XOUT and YOUT.
The output of the ADXL204 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
A/D sampling frequency to minimize aliasing. The analog
bandwidth can be further decreased to reduce noise and
improve resolution.
The ADXL204 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’s bandwidth). The user
should 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 ADXL204 is determined by
rmsNoise = (170 μg/√Hz) × (√BW×1.6)
At 100 Hz the noise is
rmsNoise = (170 μg/√Hz) × (√BW×1.6) = 2.15 mg
Often, the peak value of the noise is desired. Peak-to-peak noise
can only be estimated by statistical methods. Table 7 is useful
for estimating the probabilities of exceeding various peak
values, given the rms value.
Table 7. Estimation of Peak-to-Peak Noise
Peak-to-Peak Value
% of Time Noise Exceeds
Nominal Peak-to-Peak Value
2 × rms 32
4 × rms 4.6
6 × rms 0.27
8 × rms 0.006
ADXL204
Rev. A | Page 11 of 12
Peak-to-peak noise values give the best estimate of the uncertainty
in a single measurement and is estimated by 6 × rms. Table 8
gives the typical noise output of the ADXL204 for various CX
and CY values.
Table 8. Filter Capacitor Selection (CX, CY)
Bandwidth(Hz)
CX, CY
(μF)
RMS Noise
(mg)
Peak-to-Peak Noise
Estimate (mg)
10 0.47 0.7 4.1
50 0.1 1.5 9.1
100 0.047 2.2 12.9
500 0.01 4.8 28.8
USING THE ADXL204 WITH OPERATING VOLTAGES
OTHER THAN 3.3 V
The ADXL204 is tested and specified at VS = 3.3 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 ADXL204 output is ratiometric, so the output sensitivity, or
scale factor, varies proportionally to supply voltage. At VS = 3 V,
the output sensitivity is typically 560 mV/g. At VS = 5 V, the
output sensitivity is typically 1000 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. At VS = 5 V, the noise density is
typically 110 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. This
means at VS = 3 V, the self-test response is approximately
equivalent to 150 mV, or equivalent to 270 mg (typical). At
VS = 5 V, the self-test response is approximately equivalent to
750 mV, or equivalent to 750 mg (typical).
The supply current decreases as the supply voltage decreases.
Typical current consumption at VDD = 5 V is 750 μA.
USING THE ADXL204 AS A DUAL-AXIS TILT SENSOR
One of the most popular applications of the ADXL204 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 is 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.
ADXL204
Rev. A | Page 12 of 12
OUTLINE DIMENSIONS
BOTTOM VIEW
1
3
5
7
0.64
1.90
2.50
2.50
0.38 DIAMETER
0.50 DIAMETER
1.27
1.27
1.27
4.50
SQ
5.00
SQ
TOP VIEW
R 0.38 0.20
1.78
R 0.20
Figure 23. 8-Terminal Ceramic Leadless Chip Carrier [LCC]
(E-8)
Dimensions shown in millimeters
ORDERING GUIDE
Model Number of Axes
Specified
Voltage (V) Temperature Range Package Description
Package
Option
ADXL204CE 2 3.3 –40°C to +125°C 8-Terminal Ceramic Leadless Chip Carrier (LCC) E-8
ADXL204CE-REEL 2 3.3 –40°C to +125°C 8-Terminal Ceramic Leadless Chip Carrier (LCC) E-8
ADXL204EB Evaluation Board
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D05512-0-3/06(A)
T TTT
