Small and Thin ±2 g Accelerometer
ADXL322
FEATURES
GENERAL DESCRIPTION
Small and thin
4 mm × 4 mm × 1.45 mm LFCSP package
2 mg resolution at 60 Hz
Wide supply voltage range: 2.4 V to 6 V
Low power: 340 μA at VS = 2.4 V (typ)
Good zero g bias stability
Good sensitivity accuracy
X-axis and Y-axis aligned to within 0.1° (typ)
BW adjustment with a single capacitor
Single-supply operation
10,000 g shock survival
Pb Free: Compatible with Sn/Pb and Pb-free solder processes
The ADXL322 is a small, thin, low power, complete, dual-axis
accelerometer with signal conditioned voltage outputs, which
are all on a single monolithic IC. The product measures acceleration with a full-scale range of ±2 g (typical). It can also
measure both dynamic acceleration (vibration) and static
acceleration (gravity).
The ADXL322’s typical noise floor is 220 μg/√Hz, which allows
signals below 2 mg to be resolved in tilt-sensing applications
using narrow bandwidths (<60 Hz).
The user selects the bandwidth of the accelerometer using
capacitors CX and CY at the XOUT and YOUT pins. Bandwidths
of 0.5 Hz to 2.5 kHz can be selected to suit the application.
APPLICATIONS
The ADXL322 is available in a 4 mm × 4 mm × 1.45 mm,
16-lead, plastic LFCSP.
Cost-sensitive motion- and tilt-sensing applications
Smart hand-held devices
Mobile phones
Sports and health-related devices
PC security and PC peripherals
FUNCTIONAL BLOCK DIAGRAM
+3V
VS
ADXL322
CDC
AC
AMP
DEMOD
OUTPUT
AMP
OUTPUT
AMP
SENSOR
COM
ST
RFILT
32kΩ
YOUT
CY
XOUT
CX
05589-001
RFILT
32kΩ
Figure 1.
Rev. 0
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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.
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www.analog.com
Tel: 781.329.4700
Fax: 781.461.3113
© 2007 Analog Devices, Inc. All rights reserved.
ADXL322
SPECIFICATIONS
TA = 25°C, VS = 3 V, CX = CY = 0.1 μF, Acceleration = 0 g, unless otherwise noted 1 .
Table 1.
Parameter
SENSOR INPUT
Measurement Range
Nonlinearity
Package Alignment Error
Alignment Error
Cross-Axis Sensitivity
SENSITIVITY (RATIOMETRIC) 2
Sensitivity at XOUT, YOUT
Sensitivity Change due to Temperature 3
ZERO g BIAS LEVEL (RATIOMETRIC)
0 g Voltage at XOUT, YOUT
Initial 0 g Bias Deviation from Ideal
0 g Offset Vs. Temperature
NOISE PERFORMANCE
Noise Density
FREQUENCY RESPONSE 4
CX, CY Range 5
RFILT Tolerance
Sensor Resonant Frequency
SELF-TEST 6
Logic Input Low
Logic Input High
ST Input Resistance to Ground
Output Change at XOUT, YOUT
OUTPUT AMPLIFIER
Output Swing Low
Output Swing High
POWER SUPPLY
Operating Voltage Range
Quiescent Supply Current
Turn-On Time 7
TEMPERATURE
Operating Temperature Range
Conditions
Each axis
Min
Max
X sensor to Y sensor
Unit
g
%
Degrees
Degrees
%
±2
±0.2
±1
±0.1
±2
% of full scale
Each axis
VS = 3 V
VS = 3 V
Each axis
VS = 3 V
Typ
378
420
0.01
462
mV/g
%/°C
1.3
1.5
±50
<±0.5
1.7
V
mg
mg/°C
at 25°C
220
0.002
μg/√Hz rms
32 ± 15%
5.5
10
μF
kΩ
kHz
Self-test 0 to 1
0.6
2.4
50
125
V
V
kΩ
mV
No load
No load
0.2
2.7
V
V
T
2.4
6
V
mA
ms
70
°C
0.45
20
−20
1
All minimum and maximum specifications are guaranteed. Typical specifications are not guaranteed.
Sensitivity is essentially ratiometric to VS. For VS = 2.7 V to 3.3 V, sensitivity is 138 mV/V/g to 142 mV/V/g typical.
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.
2
Rev. 0 | Page 3 of 16
