Small, Low Power, 3-Axis ±3 g
Accelerometer
ADXL337
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.
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 ©2010 Analog Devices, Inc. All rights reserved.
FEATURES
3-axis sensing
Small, low profile package
3 mm × 3 mm × 1.45 mm LFCSP
Low power: 300 μA (typical)
Single-supply operation: 1.8 V to 3.6 V
10,000 g shock survival
Excellent temperature stability
Bandwidth adjustment with a single capacitor per axis
RoHS/WEEE and lead-free compliant
APPLICATIONS
Cost-sensitive, low power, motion- and tilt-sensing applications
Mobile devices
Gaming systems
Disk drive protection
Image stabilization
Sports and health devices
GENERAL DESCRIPTION
The ADXL337 is a small, thin, low power, complete 3-axis
accelerometer with signal conditioned voltage outputs. The
product measures acceleration with a minimum full-scale range
of ±3 g. It can measure the static acceleration of gravity in tilt-
sensing applications, as well as dynamic acceleration resulting
from motion, shock, or vibration.
The user selects the bandwidth of the accelerometer using the
CX, CY, and CZ capacitors at the XOUT, YOUT, and ZOUT pins.
Bandwidths can be selected to suit the application, with a range
of 0.5 Hz to 1600 Hz for X and Y axes and a range of 0.5 Hz to
550 Hz for the Z axis.
The ADXL337 is available in a small, low profile, 3 mm × 3 mm ×
1.45 mm, 16-lead, lead frame chip scale package (LFCSP_LQ).
FUNCTIONAL BLOCK DIAGRAM
ADXL337
3-AXIS
SENSOR
DEMODULATOR
OUTPUT
AMPLIFIERS
AC
AMPLIFIER
GND ST
+3
V
~32kΩX
OUT
C
X
C
Y
C
Z
Y
OUT
C
DC
V
S
Z
OUT
~32kΩ
~32kΩ
09358-001
Figure 1.
ADXL337
Rev. 0 | Page 2 of 16
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 ...................................................................... 10
Mechanical Sensor ...................................................................... 10
Performance ................................................................................ 10
Applications Information .............................................................. 11
Power Supply Decoupling ......................................................... 11
Setting the Bandwidth Using CX, CY, and CZ .......................... 11
Self Test ........................................................................................ 11
Design Trade-Offs for Selecting Filter Characteristics: The
Noise/BW Trade-Off .................................................................. 11
Use with Operating Voltages Other than 3 V ............................ 12
Axes of Acceleration Sensitivity ............................................... 12
Layout and Design Recommendations ................................... 13
Outline Dimensions ....................................................................... 14
Ordering Guide .......................................................................... 14
REVISION HISTORY
10/10—Revision 0: Initial Version
ADXL337
Rev. 0 | Page 3 of 16
SPECIFICATIONS
TA = 25°C, VS = 3 V, CX = CY = CZ = 0.1 μF, acceleration = 0 g, unless otherwise noted. All minimum and maximum specifications are
guaranteed. Typical specifications are not guaranteed.
Table 1.
Parameter Test Conditions/Comments Min Typ Max Unit
SENSOR INPUT Each axis
Measurement Range ±3 ±3.6 g
Nonlinearity % of full scale ±0.3 %
Package Alignment Error ±1 Degrees
Interaxis Alignment Error ±0.1 Degrees
Cross-Axis Sensitivity1 ±1 %
SENSITIVITY (RATIOMETRIC)2 Each axis
Sensitivity at XOUT, YOUT, ZOUT V
S = 3 V 270 300 330 mV/g
Sensitivity Change Due to Temperature3 V
S = 3 V ±0.01 %/°C
0 g BIAS LEVEL (RATIOMETRIC)
0 g Voltage at XOUT, YOUT V
S = 3 V 1.35 1.5 1.65 V
0 g Voltage at ZOUT V
S = 3 V 1.2 1.5 1.8 V
0 g Offset vs. Temperature XOUT, YOUT ±1.1 mg/°C
0 g Offset vs. Temperature ZOUT ±1.6 mg/°C
NOISE PERFORMANCE
Noise Density XOUT, YOUT 175 μg/√Hz rms
Noise Density ZOUT 300 μg/√Hz rms
FREQUENCY RESPONSE4
Bandwidth XOUT, YOUT5 No external filter 1600 Hz
Bandwidth ZOUT5 No external filter 550 Hz
RFILT Tolerance 32 ± 15% kΩ
Sensor Resonant Frequency 5.5 kHz
SELF TEST6
Logic Input Low 0.6 V
Logic Input High 2.4 V
ST Actuation Current 60 μA
Output Change at XOUT Self test 0 to 1 −150 −325 −600 mV
Output Change at YOUT Self test 0 to 1 +150 +325 +600 mV
Output Change at ZOUT Self test 0 to 1 +150 +550 +1000 mV
OUTPUT AMPLIFIER
Output Swing Low No load 0.1 V
Output Swing High No load 2.8 V
POWER SUPPLY
Operating Voltage Range7 1.8 3.0 3.6 V
Supply Current VS = 3 V 300 μA
Turn-On Time8 No external filter 1 ms
TEMPERATURE
Operating Temperature Range −40 +85 °C
1 Defined as coupling between any two axes.
2 Sensitivity is essentially ratiometric to VS.
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 filter capacitors (CX, CY, CZ).
5 Bandwidth with external capacitors = 1/(2 × π × 32 kΩ × C). For CX, CY = 0.003 μF, bandwidth = 1.6 kHz. For CZ = 0.01 μF, bandwidth = 500 Hz. For CX, CY, CZ = 10 μF,
bandwidth = 0.5 Hz.
6 Self test response changes cubically with VS.
7 Tested at 3.0 V and guaranteed by design only (not tested) to work over the full range from 1.8 V to 3.6 V.
8 Turn-on time is dependent on CX, CY, CZ and is approximately 160 × (CX or CY or CZ) + 1, where CX, CY, and CZ are in μF and the resulting turn-on time is in ms.
ADXL337
Rev. 0 | Page 4 of 16
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter Rating
Acceleration (Any Axis, Unpowered) 10,000 g
Acceleration (Any Axis, Powered) 10,000 g
VS −0.3 V to +3.6 V
All Other Pins (GND − 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.
ESD CAUTION
ADXL337
Rev. 0 | Page 5 of 16
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
RES
1
ST
2
RES
3
Y
OUT 4
NC
12
NC
11
NC
10
NC
9
X
OUT
GND
GND
NC
5678
16
Z
OUT
15
V
S
14
V
S
13
NC
ADXL337
TOP VIEW
(Not to Scale)
+Z
+X
+Y
09358-003
NOTES
1. NC = NO CONNECT.
2
. EXPOSED PAD IS NOT INTERNALLY
CONNECTED BUT SHOULD BE SOLDERED
FOR MECHANICAL INTEGRITY.
Figure 2. Pin Configuration
Table 3. Pin Function Descriptions
Pin No. Mnemonic Description
1, 3 RES Reserved. This pin must be connected to GND or left open.
2 ST Self Test.
4 YOUT Y Channel Output.
5 XOUT X Channel Output.
6, 7 GND Must be connected to ground.
8 to 13 NC Not internally connected.
14 VS Supply Voltage (3.0 V typical).
15 VS Supply Voltage (3.0 V typical).
16 ZOUT Z Channel Output.
EPAD Exposed Pad. Not internally connected but should be soldered for mechanical integrity.
ADXL337
Rev. 0 | Page 6 of 16
TYPICAL PERFORMANCE CHARACTERISTICS
N > 250 for all typical performance plots, unless otherwise noted. (N is the number of parts tested and used to produce the histograms.)
0
5
10
15
20
25
1.40
1.41
1.42
1.43
1.44
1.45
1.46
1.47
1.48
1.49
1.50
1.51
1.52
1.53
1.54
1.55
1.56
1.57
1.58
1.59
1.60
PERCENT OF POPUL
A
TION
OUTPUT (V)
09358-005
Figure 3. X-Axis Zero g Bias at 25°C, VS = 3 V
0
5
10
15
20
25
1.40
1.41
1.42
1.43
1.44
1.45
1.46
1.47
1.48
1.49
1.50
1.51
1.52
1.53
1.54
1.55
1.56
1.57
1.58
1.59
1.60
PERCENT OF POPUL
A
TION
OUTPUT (V)
09358-006
Figure 4. Y-Axis Zero g Bias at 25°C, VS = 3 V
0
2
4
6
8
10
12
14
16
18
PERCENT OF POPUL
A
TION
1.40
1.41
1.42
1.43
1.44
1.45
1.46
1.47
1.48
1.49
1.50
1.51
1.52
1.53
1.54
1.55
1.56
1.57
1.58
1.59
1.60
OUTPUT (V)
09358-007
Figure 5. Z-Axis Zero g Bias at 25°C, VS = 3 V
0
5
10
15
20
25
30
35
40
45
–0.35
–0.34
–0.33
–0.32
–0.31
–0.30
–0.29
–0.28
–0.27
–0.26
–0.25
PERCENT OF POPUL
A
TION
OUTPUT CHANGE DUE TO SELF TEST (V)
0
9358-008
Figure 6. X-Axis Self-Test Response at 25°C, VS = 3 V
OUTPUT CHANGE DUE TO SELF TEST (V)
0
5
10
15
20
25
30
35
40
45
0.18
0.19
0.20
0.21
0.22
0.23
0.24
0.25
0.26
0.27
0.28
0.29
0.30
0.31
0.32
0.33
0.34
0.35
0.36
0.37
0.38
PERCENT OF POPUL
A
TION
09358-009
Figure 7. Y-Axis Self-Test Response at 25°C, VS = 3 V
0
10
20
30
40
50
60
0.44 0.46 0.48 0.50 0.52 0.54 0.56 0.58 0.60 0.62 0.64
OUTPUT CHANGE DUE TO SELF TEST (V)
PERCENT OF POPUL
A
TION
0
9358-010
Figure 8. Z-Axis Self-Test Response at 25°C, VS = 3 V
ADXL337
Rev. 0 | Page 7 of 16
0
5
10
15
20
25
30
35
40
45
–2.50
–2.25
–2.00
–1.75
–1.50
–1.25
–1.00
–0.75
–0.50
–0.25
0
0.25
0.50
0.75
1.00
PERCENT OF POPUL
A
TION
TEMPERATURE COEFFICIENT (mg/°C)
09358-011
Figure 9. X-Axis Zero g Bias Temperature Coefficient, VS = 3 V
0
5
10
15
20
25
30
35
–2.50
–2.25
–2.00
–1.75
–1.50
–1.25
–1.00
–0.75
–0.50
–0.25
0
0.25
0.50
0.75
1.00
PERCENT OF POPUL
A
TION
TEMPERATURE COEFFICIENT (mg/°C)
09358-012
Figure 10. Y-Axis Zero g Bias Temperature Coefficient, VS = 3 V
0
5
10
15
20
25
30
PERCENT OF POPUL
A
TION
TEMPERATURE COEFFICIENT (mg/°C)
0
9358-013
–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
Figure 11. Z-Axis Zero g Bias Temperature Coefficient, VS = 3 V
1.40
1.42
1.44
1.46
1.48
1.50
1.52
1.54
1.56
1.58
1.60
–40 –20 0 20 40 60 80 100
OUTPUT (V)
TEMPERATURE (°C)
09358-014
Figure 12. X-Axis Zero g Bias vs. Temperature—Eight Parts Soldered to PCB
1.40
1.42
1.44
1.46
1.48
1.50
1.52
1.54
1.56
1.58
1.60
–40 –20 0 20 40 60 80 100
OUTPUT (V)
TEMPERATURE (°C)
09358-015
Figure 13. Y-Axis Zero g Bias vs. Temperature—Eight Parts Soldered to PCB
1.40
1.42
1.44
1.46
1.48
1.50
1.52
1.54
1.56
1.58
1.60
–60 –40 –20 0 20 40 60 80 100
OUTPUT (V)
TEMPERATURE (°C)
09358-016
Figure 14. Z-Axis Zero g Bias vs. Temperature—Eight Parts Soldered to PCB
ADXL337
Rev. 0 | Page 8 of 16
0
5
10
15
20
25
30
35
40
45
50
0.290
0.293
0.296
0.299
0.302
0.305
0.308
0.311
0.314
0.317
PERCENT OF POPUL
A
TION
SENSITIVITY (V/g)
09358-017
Figure 15. X-Axis Sensitivity at 25°C, VS = 3 V
0
10
20
30
40
50
60
0.290
0.293
0.296
0.299
0.302
0.305
0.308
0.311
0.314
0.317
0.320
PERCENT OF POPUL
A
TION
SENSITIVITY (V/g)
09358-018
Figure 16. Y-Axis Sensitivity at 25°C, VS = 3 V
0
5
10
15
20
25
30
35
40
45
50
0.290
0.293
0.296
0.299
0.302
0.305
0.308
0.311
0.314
0.317
0.320
PERCENT OF POPUL
A
TION
SENSITIVITY (V/
g
)
09358-019
Figure 17. Z-Axis Sensitivity at 25°C, VS = 3 V
0.27
0.28
0.29
0.30
0.31
0.32
0.33
–40 –20 0 20 40 60 80 100
SENSITIVITY (V/g)
TEMPERATURE (°C)
09358-020
Figure 18. X-Axis Sensitivity vs. Temperature,
Eight Parts Soldered to PCB, VS = 3 V
0.27
0.28
0.29
0.30
0.31
0.32
0.33
–40 –20 0 20 40 60 80 100
SENSITIVITY (V/
g
)
TEMPERATURE (°C)
09358-021
Figure 19. Y-Axis Sensitivity vs. Temperature,
Eight Parts Soldered to PCB, VS = 3 V
0.27
0.28
0.29
0.30
0.31
0.32
0.33
–40 –20 0
SENSITIVITY (V/
g
)
TEMPERATURE (°C)
09358-022
20 40 60 80 100
Figure 20. Z-Axis Sensitivity vs. Temperature,
Eight Parts Soldered to PCB, VS = 3 V
ADXL337
Rev. 0 | Page 9 of 16
0
50
100
150
200
250
300
350
400
1.5 2.0 2.5 3.0 3.5 4.0
CURRENT (µA)
SUPPLY VOLTAGE (V)
09358-023
Figure 21. Typical Current Consumption vs. Supply Voltage
09358-024
TIME (1ms/DIV)
POWER,
1V/DIV
Y
OUT
,
500mV/DIV
X
OUT
,
500mV/DIV
C
X
= C
Y
= C
Z
= 0.001µF
Z
OUT
,
500mV/DIV
OUTPUTS ARE OFFSET FOR CLARITY
Figure 22. Typical Turn-On Time, VS = 3 V
ADXL337
Rev. 0 | Page 10 of 16
THEORY OF OPERATION
The ADXL337 is a complete 3-axis acceleration measurement
system. The ADXL337 has a measurement range of ±3 g minimum.
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
that are proportional to acceleration. The accelerometer can
measure the static acceleration of gravity in tilt-sensing applications
as well as dynamic acceleration resulting from motion, shock,
or vibration.
The sensor is a polysilicon surface micromachined structure
built on top of a 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 moving mass and unbalances the differential capacitor resulting
in a sensor output whose amplitude is proportional to acceleration.
Phase-sensitive demodulation techniques are then used to
determine the magnitude and direction of the acceleration.
The demodulator output is amplified and brought off chip
through a 32 kΩ resistor. The user then sets the signal bandwidth
(BW) of the device by adding a capacitor. This filtering improves
measurement resolution and helps prevent aliasing.
MECHANICAL SENSOR
The ADXL337 uses a single structure for sensing the X, Y, and Z axes.
As a result, the three axes sense directions are highly orthogonal
with little cross-axis sensitivity. Mechanical misalignment of the
sensor die to the package is the chief source of cross-axis sensitivity.
Mechanical misalignment can be calibrated out at the system level.
PERFORMANCE
Rather than using additional temperature compensation circuitry,
innovative design techniques ensure that high performance is built
into the ADXL337. As a result, there is neither quantization error
nor nonmonotonic behavior, and temperature hysteresis is very
low (typically less than 3 mg over the −25°C to +85°C temperature
range).
ADXL337
Rev. 0 | Page 11 of 16
APPLICATIONS INFORMATION
POWER SUPPLY DECOUPLING
For most applications, a single 0.1 μF capacitor, CDC, placed
close to the ADXL337 supply pins adequately decouples the
accelerometer from noise on the power supply. However, in
applications where noise is present at the 50 kHz internal clock
frequency (or any harmonic thereof), additional care in power
supply bypassing is required because this noise can cause errors
in acceleration measurement. If additional decoupling is needed, a
100 Ω (or smaller) resistor or ferrite bead can be inserted in the
supply line. Additionally, a larger bulk bypass capacitor (1 μF or
greater) can be added in parallel to CDC. Ensure that the connection
from the ADXL337 ground to the power supply ground is low
impedance because noise transmitted through ground has a
similar effect as noise transmitted through VS.
SETTING THE BANDWIDTH USING CX, CY, AND CZ
The ADXL337 has provisions for band limiting the XOUT, YOUT,
and ZOUT 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, Z))
or more simply
f–3 dB = 5 μF/C(X, Y, Z)
The tolerance of the internal resistor (RFILT) typically varies as
much as ±15% of its nominal value (32 kΩ), and the bandwidth
varies accordingly. A minimum capacitance of 0.0047 μF for CX,
CY, and CZ is recommended in all cases.
Table 4. Filter Capacitor Selection, CX, CY, and CZ
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 accelerometer beam.
The resulting movement of the beam allows the user to test if
the accelerometer is functional. The typical change in output is
−1.08 g (corresponding to −325 mV) in the X-axis, +1.08 g (or
+325 mV) on the Y-axis, and +1.83 mg (or +550 mV) on the
Z-axis. This ST pin can be left open circuit or connected to
common (GND) in normal use.
Never expose the ST pin to voltages greater than VS + 0.3 V. If
this cannot be guaranteed due to the system design (for instance, if
there are multiple supply voltages), then a low VF clamping
diode between ST and VS is recommended.
DESIGN TRADE-OFFS FOR SELECTING FILTER
CHARACTERISTICS: THE NOISE/BW TRADE-OFF
The selected accelerometer bandwidth ultimately determines
the measurement resolution (smallest detectable acceleration).
Filtering can be used to lower the noise floor to improve the
resolution of the accelerometer. Resolution is dependent on the
analog filter bandwidth at XOUT, YOUT, and ZOUT.
The output of the ADXL337 has a typical bandwidth of greater
than 500 Hz. 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 decreased further to reduce noise
and improve resolution.
The ADXL337 noise has the characteristics of white Gaussian
noise, which contributes equally at all frequencies and is described
in terms of μg/√Hz (the noise is proportional to the square root
of the accelerometer 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 ADXL337 is determined by
rms Noise = Noise Density × )1.6( ×BW
It is often useful to know the peak value of the noise. Peak-to-peak
noise can only be estimated by statistical methods. Table 5 is useful
for estimating the probabilities of exceeding various peak values,
given the rms value.
Table 5. Estimation of Peak-to-Peak Noise
Peak-to-Peak Value
Percent 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
ADXL337
Rev. 0 | Page 12 of 16
USE WITH OPERATING VOLTAGES OTHER THAN 3 V
The ADXL337 is tested and specified at VS = 3 V; however, it
can be powered with VS as low as 1.8 V or as high as 3.6 V. Note
that some performance parameters change as the supply voltage
is varied.
The ADXL337 output is ratiometric; therefore, the output
sensitivity (or scale factor) varies proportionally to the supply
voltage. At VS = 3.6 V, the output sensitivity is typically 360 mV/g.
At VS = 2 V, the output sensitivity is typically 195 mV/g.
The zero g bias output is also ratiometric; therefore, 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 = 3.6 V, the X-
and Y-axis noise density is typically 120 μg/√Hz, and at VS =
2 V, the X- and Y-axis noise density is typically 270 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, the self test response in volts
is roughly proportional to the cube of the supply voltage. For
example, at VS = 3.6 V, the self test response for the ADXL337 is
approximately −560 mV for the X-axis, +560 mV for the Y-axis,
and +950 mV for the Z-axis.
At VS = 2 V, the self test response is approximately −96 mV for
the X-axis, +96 mV for the Y-axis, and −163 mV for the Z-axis.
The supply current decreases as the supply voltage decreases.
Typical current consumption at VS = 3.6 V is 375 μA, and
typical current consumption at VS = 2 V is 200 μA.
AXES OF ACCELERATION SENSITIVITY
The axes of sensitivity for the accelerometer are shown in Figure 23,
and Figure 24 shows the output response when the accelerometer is
oriented parallel to each of these axes.
A
Z
A
Y
A
X
TOP
09358-030
Figure 23. Axes of Acceleration Sensitivity, Corresponding Output Voltage
Increases When Accelerated Along the Sensitive Axis
XOUT = –1g
YOUT = 0g
ZOUT = 0g
GRAVITY
OUT = 0g
OUT = 1g
OUT = 0g
XOUT = 0g
YOUT = –1g
ZOUT = 0g
XOUT = 1g
YOUT = 0g
ZOUT = 0g
XOUT = 0g
YOUT = 0g
ZOUT = 1g
XOUT = 0g
YOUT = 0g
ZOUT = –1g
TOP
TOP TOP
TOP
TOP
09358-031
Figure 24. Output Response vs. Orientation to Gravity
ADXL337
Rev. 0 | Page 13 of 16
LAYOUT AND DESIGN RECOMMENDATIONS
The recommended soldering profile is shown in Figure 25 followed by a description of the profile features in Table 6. The recommended
PCB layout or solder land drawing is shown in Figure 26.
t
P
t
L
t
25°C
t
S
PREHEAT
CRITICAL ZONE
T
L
TO T
P
TEMPERATURE
TIME
RAMP-DOWN
RAMP-UP
T
SMIN
T
SMAX
T
P
T
L
09358-002
Figure 25. Recommended Soldering Profile
Table 6. Recommended Soldering Profile
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
Maximum Temperature (TSMAX) 150°C 200°C
Time (TSMIN to TSMAX), tS 60 sec to 120 sec 60 sec to 180 sec
TSMAX to TL
Ramp-Up Rate 3°C/sec maximum 3°C/sec maximum
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 (t25°C) 6 minutes maximum 8 minutes maximum
C
ENTER PAD IS NOT
INTERNALLY CONNECTED
BUT SHOULD BE SOLDERED
FOR MECHANICAL INTEGRITY
0.40
MAX
0.50 0.25
1.60
0.50
0.25
3
3
0.25
MAX
1.60
DIMENSIONS SHOWN IN MILLIMETERS
09358-004
Figure 26. Recommended PCB Layout
ADXL337
Rev. 0 | Page 14 of 16
OUTLINE DIMENSIONS
3.10
3.00 SQ
2.90
0.30
0.25
0.18
1.70
1.60 SQ
1.50
1
0.50
BSC
BOTTOM VIEW
TOP VIEW
16
5
8
9
12
13
4
EXPOSED
PAD
PIN1
INDICATOR
0.45
0.40
0.35
SEATING
PLANE
0.05 MAX
0.02 NOM
0.152 REF
0.20 MIN
COPLANARITY
0.08
PIN 1
INDICATOR
1.50
1.45
1.40
FORPROPERCONNECTIONOF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
04-27-2010-A
Figure 27. 16-Lead Lead Frame Chip Scale Package [LFCSP_LQ]
3 mm × 3 mm Body, Thick Quad
(CP-16-28)
Dimensions shown in millimeters
ORDERING GUIDE
Model1 Measurement Range Specified Voltage Temperature Range Package Description Package Option
ADXL337BCPZ–RL ±3 g 3 V −40°C to +85°C 16-Lead LFCSP_LQ CP-16-28
ADXL337BCPZ–RL7 ±3 g 3 V −40°C to +85°C 16-Lead LFCSP_LQ CP-16-28
EVAL-ADXL337Z Evaluation Board
1 Z = RoHS Compliant Part.
ADXL337
Rev. 0 | Page 15 of 16
NOTES
ADXL337
Rev. 0 | Page 16 of 16
NOTES
©2010 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D09358-0-10/10(0)