AD ADXL337

Small, Low Power, 3-Axis ±3 g
Accelerometer
ADXL337
FEATURES
GENERAL DESCRIPTION
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
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 tiltsensing 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.
APPLICATIONS
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).
Cost-sensitive, low power, motion- and tilt-sensing applications
Mobile devices
Gaming systems
Disk drive protection
Image stabilization
Sports and health devices
FUNCTIONAL BLOCK DIAGRAM
+3V
VS
ADXL337
OUTPUT
AMPLIFIERS
AC
AMPLIFIER
CDC
DEMODULATOR
~32kΩ
XOUT
CX
~32kΩ
YOUT
CY
3-AXIS
SENSOR
~32kΩ
ZOUT
CZ
ST
09358-001
GND
Figure 1.
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.
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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.
ADXL337
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications Information .............................................................. 11
Applications ....................................................................................... 1
Power Supply Decoupling ......................................................... 11
General Description ......................................................................... 1
Setting the Bandwidth Using CX, CY, and CZ .......................... 11
Functional Block Diagram .............................................................. 1
Self Test ........................................................................................ 11
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Design Trade-Offs for Selecting Filter Characteristics: The
Noise/BW Trade-Off .................................................................. 11
Absolute Maximum Ratings............................................................ 4
Use with Operating Voltages Other than 3 V ............................ 12
ESD Caution .................................................................................. 4
Axes of Acceleration Sensitivity ............................................... 12
Pin Configuration and Function Descriptions ............................. 5
Layout and Design Recommendations ................................... 13
Typical Performance Characteristics ............................................. 6
Outline Dimensions ....................................................................... 14
Theory of Operation ...................................................................... 10
Ordering Guide .......................................................................... 14
Mechanical Sensor...................................................................... 10
Performance ................................................................................ 10
REVISION HISTORY
10/10—Revision 0: Initial Version
Rev. 0 | Page 2 of 16
ADXL337
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
SENSOR INPUT
Measurement Range
Nonlinearity
Package Alignment Error
Interaxis Alignment Error
Cross-Axis Sensitivity 1
SENSITIVITY (RATIOMETRIC) 2
Sensitivity at XOUT, YOUT, ZOUT
Sensitivity Change Due to Temperature 3
0 g BIAS LEVEL (RATIOMETRIC)
0 g Voltage at XOUT, YOUT
0 g Voltage at ZOUT
0 g Offset vs. Temperature XOUT, YOUT
0 g Offset vs. Temperature ZOUT
NOISE PERFORMANCE
Noise Density XOUT, YOUT
Noise Density ZOUT
FREQUENCY RESPONSE 4
Bandwidth XOUT, YOUT 5
Bandwidth ZOUT5
RFILT Tolerance
Sensor Resonant Frequency
SELF TEST 6
Logic Input Low
Logic Input High
ST Actuation Current
Output Change at XOUT
Output Change at YOUT
Output Change at ZOUT
OUTPUT AMPLIFIER
Output Swing Low
Output Swing High
POWER SUPPLY
Operating Voltage Range 7
Supply Current
Turn-On Time 8
TEMPERATURE
Operating Temperature Range
Test Conditions/Comments
Each axis
Min
Typ
±3
±3.6
±0.3
±1
±0.1
±1
Each axis
VS = 3 V
VS = 3 V
270
300
±0.01
330
mV/g
%/°C
VS = 3 V
VS = 3 V
1.35
1.2
1.5
1.5
±1.1
±1.6
1.65
1.8
V
V
mg/°C
mg/°C
% of full scale
No external filter
No external filter
Self test 0 to 1
Self test 0 to 1
Self test 0 to 1
−150
+150
+150
No load
No load
Max
g
%
Degrees
Degrees
%
175
300
μg/√Hz rms
μg/√Hz rms
1600
550
32 ± 15%
5.5
Hz
Hz
kΩ
kHz
0.6
2.4
60
−325
+325
+550
V
V
μA
mV
mV
mV
−600
+600
+1000
0.1
2.8
1.8
VS = 3 V
No external filter
−40
1
Unit
3.0
300
1
V
V
3.6
V
μA
ms
+85
°C
Defined as coupling between any two axes.
Sensitivity is essentially ratiometric to VS.
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.
2
3
Rev. 0 | Page 3 of 16
ADXL337
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter
Acceleration (Any Axis, Unpowered)
Acceleration (Any Axis, Powered)
VS
All Other Pins
Output Short-Circuit Duration
(Any Pin to Common)
Temperature Range (Powered)
Temperature Range (Storage)
Rating
10,000 g
10,000 g
−0.3 V to +3.6 V
(GND − 0.3 V) to (VS + 0.3 V)
Indefinite
−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.
ESD CAUTION
Rev. 0 | Page 4 of 16
ADXL337
1
ST
2
VS
VS
NC
16
15
14
13
ADXL337
TOP VIEW
(Not to Scale)
12
NC
11
NC
10
NC
9
NC
+Y
+X
5
6
7
8
NC
4
GND
YOUT
+Z
GND
3
XOUT
RES
09358-003
RES
ZOUT
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
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.
1, 3
2
4
5
6, 7
8 to 13
14
15
16
Mnemonic
RES
ST
YOUT
XOUT
GND
NC
VS
VS
ZOUT
EPAD
Description
Reserved. This pin must be connected to GND or left open.
Self Test.
Y Channel Output.
X Channel Output.
Must be connected to ground.
Not internally connected.
Supply Voltage (3.0 V typical).
Supply Voltage (3.0 V typical).
Z Channel Output.
Exposed Pad. Not internally connected but should be soldered for mechanical integrity.
Rev. 0 | Page 5 of 16
ADXL337
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.)
25
45
PERCENT OF POPULATION
PERCENT OF POPULATION
40
20
15
10
5
35
30
25
20
15
10
5
0
OUTPUT CHANGE DUE TO SELF TEST (V)
Figure 3. X-Axis Zero g Bias at 25°C, VS = 3 V
09358-008
–0.25
–0.26
–0.27
–0.28
–0.29
–0.30
–0.31
–0.32
–0.33
–0.34
–0.35
OUTPUT (V)
09358-005
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
0
Figure 6. X-Axis Self-Test Response at 25°C, VS = 3 V
25
45
20
PERCENT OF POPULATION
PERCENT OF POPULATION
40
15
10
5
35
30
25
20
15
10
5
0
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
OUTPUT CHANGE DUE TO SELF TEST (V)
09358-009
OUTPUT (V)
09358-006
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
0
Figure 7. Y-Axis Self-Test Response at 25°C, VS = 3 V
Figure 4. Y-Axis Zero g Bias at 25°C, VS = 3 V
60
18
16
PERCENT OF POPULATION
12
10
8
6
4
40
30
20
10
0
OUTPUT (V)
09358-007
0
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)
Figure 8. Z-Axis Self-Test Response at 25°C, VS = 3 V
Figure 5. Z-Axis Zero g Bias at 25°C, VS = 3 V
Rev. 0 | Page 6 of 16
09358-010
2
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 POPULATION
50
14
45
1.60
40
1.58
1.56
35
1.54
OUTPUT (V)
30
25
20
15
1.50
1.48
09358-011
1.00
0.75
0.50
0
0.25
–0.25
–0.50
–0.75
–1.00
–1.25
–1.50
–1.75
1.40
–40
–2.00
1.42
0
–2.25
1.44
5
Figure 9. X-Axis Zero g Bias Temperature Coefficient, VS = 3 V
–20
0
20
40
60
80
100
TEMPERATURE (°C)
09358-014
1.46
TEMPERATURE COEFFICIENT (mg/°C)
Figure 12. X-Axis Zero g Bias vs. Temperature—Eight Parts Soldered to PCB
35
1.60
1.58
30
1.56
25
1.54
OUTPUT (V)
PERCENT OF POPULATION
1.52
10
–2.50
PERCENT OF POPULATION
ADXL337
20
15
1.52
1.50
1.48
1.46
10
1.44
5
TEMPERATURE COEFFICIENT (mg/°C)
1.40
–40
09358-012
1.00
0.75
0.50
0.25
0
–0.25
–0.50
–0.75
–1.00
–1.25
–1.50
–1.75
–2.00
–2.25
–2.50
0
Figure 10. Y-Axis Zero g Bias Temperature Coefficient, VS = 3 V
–20
0
20
40
60
80
100
TEMPERATURE (°C)
09358-015
1.42
Figure 13. Y-Axis Zero g Bias vs. Temperature—Eight Parts Soldered to PCB
30
1.60
1.58
1.56
1.54
OUTPUT (V)
20
15
10
1.52
1.50
1.48
1.46
1.44
5
1.40
–60
Figure 11. Z-Axis Zero g Bias Temperature Coefficient, VS = 3 V
09358-013
3.0
2.5
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
–2.5
TEMPERATURE COEFFICIENT (mg/°C)
–40
–20
0
20
40
TEMPERATURE (°C)
60
80
100
09358-016
1.42
0
–3.0
PERCENT OF POPULATION
25
Figure 14. Z-Axis Zero g Bias vs. Temperature—Eight Parts Soldered to PCB
Rev. 0 | Page 7 of 16
ADXL337
50
0.33
0.32
40
35
SENSITIVITY (V/g)
PERCENT OF POPULATION
45
30
25
20
15
0.31
0.30
0.29
10
0.28
0.317
SENSITIVITY (V/g)
0.27
–40
0
20
40
60
80
100
TEMPERATURE (°C)
Figure 18. X-Axis Sensitivity vs. Temperature,
Eight Parts Soldered to PCB, VS = 3 V
Figure 15. X-Axis Sensitivity at 25°C, VS = 3 V
60
0.33
50
0.32
40
0.31
SENSITIVITY (V/g)
30
20
10
0.30
0.29
0.320
SENSITIVITY (V/g)
0.27
–40
–20
0
09358-018
0.317
0.314
0.311
0.308
0.305
0.302
0.299
0.296
0.293
0.290
0
20
40
60
80
100
09358-021
0.28
100
09358-022
PERCENT OF POPULATION
–20
09358-017
0.314
0.311
0.308
0.305
0.302
0.299
0.296
0.293
0.290
0
09358-020
5
TEMPERATURE (°C)
Figure 16. Y-Axis Sensitivity at 25°C, VS = 3 V
Figure 19. Y-Axis Sensitivity vs. Temperature,
Eight Parts Soldered to PCB, VS = 3 V
50
0.33
45
0.32
SENSITIVITY (V/g)
35
30
25
20
15
10
0.31
0.30
0.29
0.28
5
0.27
–40
0.320
09358-019
SENSITIVITY (V/g)
0.317
0.314
0.311
0.308
0.305
0.302
0.299
0.296
0.293
0
0.290
PERCENT OF POPULATION
40
–20
0
20
40
60
80
TEMPERATURE (°C)
Figure 20. Z-Axis Sensitivity vs. Temperature,
Eight Parts Soldered to PCB, VS = 3 V
Figure 17. Z-Axis Sensitivity at 25°C, VS = 3 V
Rev. 0 | Page 8 of 16
ADXL337
400
CX = CY = CZ = 0.001µF
350
ZOUT,
500mV/DIV
250
200
YOUT,
500mV/DIV
150
50
0
1.5
POWER,
1V/DIV
2.0
2.5
3.0
3.5
4.0
SUPPLY VOLTAGE (V)
OUTPUTS ARE OFFSET FOR CLARITY
TIME (1ms/DIV)
Figure 22. Typical Turn-On Time, VS = 3 V
Figure 21. Typical Current Consumption vs. Supply Voltage
Rev. 0 | Page 9 of 16
09358-024
XOUT,
500mV/DIV
100
09358-023
CURRENT (µA)
300
ADXL337
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.
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).
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.
Rev. 0 | Page 10 of 16
ADXL337
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))
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
or more simply
rms Noise = Noise Density × ( BW × 1.6 )
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.
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 4. Filter Capacitor Selection, CX, CY, and CZ
Table 5. Estimation of Peak-to-Peak Noise
Bandwidth (Hz)
1
10
50
100
200
500
Peak-to-Peak Value
2 × rms
4 × rms
6 × rms
8 × rms
Capacitor (μF)
4.7
0.47
0.10
0.05
0.027
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.
Rev. 0 | Page 11 of 16
Percent of Time that Noise Exceeds
Nominal Peak-to-Peak Value
32
4.6
0.27
0.006
ADXL337
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.
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.
The zero g bias output is also ratiometric; therefore, the zero g
output is nominally equal to VS/2 at all supply voltages.
AZ
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 Xand 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.
AY
TOP
AX
Figure 23. Axes of Acceleration Sensitivity, Corresponding Output Voltage
Increases When Accelerated Along the Sensitive Axis
XOUT = –1g
YOUT = 0g
ZOUT = 0g
TOP
GRAVITY
TOP
TOP
XOUT = 0g
YOUT = –1g
ZOUT = 0g
TOP
XOUT = 1g
YOUT = 0g
ZOUT = 0g
TOP
XOUT = 0g
YOUT = 0g
ZOUT = 1g
Figure 24. Output Response vs. Orientation to Gravity
Rev. 0 | Page 12 of 16
XOUT = 0g
YOUT = 0g
ZOUT = –1g
09358-031
XOUT = 0g
YOUT = 1g
ZOUT = 0g
09358-030
USE WITH OPERATING VOLTAGES OTHER THAN 3 V
ADXL337
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.
CRITICAL ZONE
TL TO TP
tP
TP
tL
TSMAX
TSMIN
tS
RAMP-DOWN
PREHEAT
09358-002
TEMPERATURE
RAMP-UP
TL
t25°C
TIME
Figure 25. Recommended Soldering Profile
Table 6. Recommended Soldering Profile
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 (t25°C)
0.40
MAX
Sn63/Pb37
3°C/sec maximum
Pb-Free
3°C/sec maximum
100°C
150°C
60 sec to 120 sec
150°C
200°C
60 sec to 180 sec
3°C/sec maximum
3°C/sec maximum
183°C
60 sec to 150 sec
240°C + 0°C/−5°C
10 sec to 30 sec
6°C/sec maximum
6 minutes maximum
217°C
60 sec to 150 sec
260°C + 0°C/−5°C
20 sec to 40 sec
6°C/sec maximum
8 minutes maximum
3
0.50
0.25
0.25
MAX
0.50
3
1.60
0.25
CENTER PAD IS NOT
INTERNALLY CONNECTED
BUT SHOULD BE SOLDERED
FOR MECHANICAL INTEGRITY
DIMENSIONS SHOWN IN MILLIMETERS
Figure 26. Recommended PCB Layout
Rev. 0 | Page 13 of 16
09358-004
1.60
ADXL337
OUTLINE DIMENSIONS
PIN 1
INDICATOR
0.30
0.25
0.18
0.50
BSC
13
PIN 1
INDICATOR
16
1
12
1.70
1.60 SQ
1.50
EXPOSED
PAD
9
TOP VIEW
1.50
1.45
1.40
0.45
0.40
0.35
4
8
BOTTOM VIEW
0.05 MAX
0.02 NOM
COPLANARITY
0.08
0.152 REF
SEATING
PLANE
5
0.20 MIN
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
04-27-2010-A
3.10
3.00 SQ
2.90
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
Model 1
ADXL337BCPZ–RL
ADXL337BCPZ–RL7
EVAL-ADXL337Z
1
Measurement Range
±3 g
±3 g
Specified Voltage
3V
3V
Temperature Range
−40°C to +85°C
−40°C to +85°C
Z = RoHS Compliant Part.
Rev. 0 | Page 14 of 16
Package Description
16-Lead LFCSP_LQ
16-Lead LFCSP_LQ
Evaluation Board
Package Option
CP-16-28
CP-16-28
ADXL337
NOTES
Rev. 0 | Page 15 of 16
ADXL337
NOTES
©2010 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D09358-0-10/10(0)
Rev. 0 | Page 16 of 16