ANALOG DEVICES ADXL337 Service Manual
Small, Low Power, 3-Axis ±3 g
V
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
Accelerometer
ADXL337
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 tiltsensing applications, as well as dynamic acceleration resulting
from motion, shock, or vibration.
The user selects the bandwidth of the accelerometer using the
C
, CY, and CZ capacitors at the X
X
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).
OUT
, Y
OUT
, and Z
OUT
pins.
FUNCTIONAL BLOCK DIAGRAM
+3
V
S
ADXL337
X
OUTPUT
AC
AMPLIFIER
C
DC
3-AXIS
SENSOR
GND ST
DEMODULATO R
Figure 1.
AMPLIFIERS
~32kΩ
~32kΩ
~32kΩ
OUT
C
X
Y
OUT
C
Y
Z
OUT
C
Z
09358-001
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 ....................................................................................... 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
REVISION HISTORY
10/10—Revision 0: Initial Version
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
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 Test Conditions/Comments Min Typ Max Unit
SENSOR INPUT Each axis
Measurement Range ±3 ±3.6
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 X
Sensitivity Change Due to Temperature3 V
OUT
, Y
, Z
V
OUT
OUT
= 3 V 270 300 330 mV/g
S
= 3 V ±0.01 %/°C
S
0 g BIAS LEVEL (RATIOMETRIC)
0 g Voltage at X
0 g Voltage at Z
0 g Offset vs. Temperature X
0 g Offset vs. Temperature Z
, Y
V
OUT
OUT
V
OUT
, Y
±1.1 mg/°C
OUT
OUT
±1.6 mg/°C
OUT
= 3 V 1.35 1.5 1.65 V
S
= 3 V 1.2 1.5 1.8 V
S
NOISE PERFORMANCE
Noise Density X
Noise Density Z
, Y
175 μg/√Hz rms
OUT
OUT
300 μg/√Hz rms
OUT
FREQUENCY RESPONSE4
Bandwidth X
Bandwidth Z
R
Tolerance 32 ± 15% kΩ
FILT
5
, Y
OUT
OUT
No external filter 1600 Hz
OUT
5
No external filter 550 Hz
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 X
Output Change at Y
Output Change at Z
Self test 0 to 1 −150 −325 −600 mV
OUT
Self test 0 to 1 +150 +325 +600 mV
OUT
Self test 0 to 1 +150 +550 +1000 mV
OUT
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.
g
Rev. 0 | Page 3 of 16
ADXL337
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)
Temperature Range (Powered) −55°C to +125°C
Temperature Range (Storage) −65°C to +150°C
Indefinite
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
2
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
S
S
OUT
Z
V
V
NC
15
14
13
12
NC
11
+Y
+X
NC
10
NC
9
NC
Y
RES
RES
OUT
1
2
ST
3
4
16
ADXL337
TOP VIEW
(Not to Scale)
+Z
5678
OUT
X
NOTES
1. NC = NO CONNECT .
. EXPOSED PAD IS NOT I NTERNALLY
CONNECTED BUT SHO ULD BE SOLDERED
FOR MECHANICAL INTEGRI TY.
NC
GND
GND
09358-003
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 Y
5 X
Y Channel Output.
OUT
X Channel Output.
OUT
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 Z
Z Channel Output.
OUT
EPAD Exposed Pad. Not internally connected but should be soldered for mechanical integrity.
Rev. 0 | Page 5 of 16
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