REV. B
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
a
Low Cost 62 g/610 g Dual Axis
iMEMS
®
Accelerometers
with Digital Output
ADXL202/ADXL210
FEATURES
2-Axis Acceleration Sensor on a Single IC Chip
Measures Static Acceleration as Well as Dynamic
Acceleration
Duty Cycle Output with User Adjustable Period
Low Power <0.6 mA
Faster Response than Electrolytic, Mercury or Thermal
Tilt Sensors
Bandwidth Adjustment with a Single Capacitor Per Axis
5 mg Resolution at 60 Hz Bandwidth
+3 V to +5.25 V Single Supply Operation
1000 g Shock Survival
APPLICATIONS
2-Axis Tilt Sensing
Computer Peripherals
Inertial Navigation
Seismic Monitoring
Vehicle Security Systems
Battery Powered Motion Sensing
A
IN
2 =
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700 World Wide Web Site: http://www.analog.com
Fax: 781/326-8703 © Analog Devices, Inc., 1999
FUNCTIONAL BLOCK DIAGRAM
DEMOD
R
FILT
32kV
R
FILT
32kV
OSCILLATOR
X SENSOR
Y SENSOR
ADXL202/
ADXL210
X OUT
Y OUT
SELF TESTX
FILTV
DD
V
DD
C
X
+3.0V TO +5.25V
C
DC
COM
Y
FILT
T2
C
Y
R
SET
C
O
U
N
T
E
R
mP
T2
T1
A(g) = (T1/T2 – 0.5)/12.5%
0g = 50% DUTY CYCLE
T2 = R
SET
/125MV
DEMOD
DUTY
CYCLE
MODULATOR
(DCM)
GENERAL DESCRIPTION
The ADXL202/ADXL210 are low cost, low power, complete
2-axis accelerometers with a measurement range of either
– 2 g/– 10 g. The ADXL202/ADXL210 can measure both dy-
namic acceleration (e.g., vibration) and static acceleration (e.g.,
gravity).
The outputs are digital signals whose duty cycles (ratio of pulse-
width to period) are proportional to the acceleration in each of
the 2 sensitive axes. These outputs may be measured directly
with a microprocessor counter, requiring no A/D converter or
glue logic. The output period is adjustable from 0.5 ms to 10 ms
via a single resistor (R
SET
). If a voltage output is desired, a
voltage output proportional to acceleration is available from the
X
FILT
and Y
FILT
pins, or may be reconstructed by filtering the
duty cycle outputs.
The bandwidth of the ADXL202/ADXL210 may be set from
0.01 Hz to 5 kHz via capacitors C
X
and C
Y
. The typical noise
floor is 500 m g/ Hz allowing signals below 5 mg to be resolved
for bandwidths below 60 Hz.
The ADXL202/ADXL210 is available in a hermetic 14-lead
Surface Mount CERPAK, specified over the 0 C to +70 C
commercial or –40 C to +85 C industrial temperature range.
iMEMS is a registered trademark of Analog Devices, Inc.