Single and Dual Axis
Automotive iMEMS® Accelerometers
a
ADXL76, ADXL269, ADXL276
FEATURES
FUNCTIONAL BLOCK DIAGRAMS
Complete Acceleration Measurement System on a
Single Monolithic IC
2-Pole Filter On-Chip
V
2
S
ADXL76
+V
S
No External Components Required for Direct Interface
to ADC or Controller
Complete Mechanical and Electrical Self-Test on Digital
Command
Sensitivity and Offset Are Ratiometric to Supply
5 V Supply Voltage with Operation Down to 4 V
Sensitive Axes in the Plane of the Chip
Linearity (0.2% of Full-Scale)
OSCILLATOR
AMP
5k⍀
V
FILTER
OUT
SENSOR
DEMODULATOR
25k⍀
SELF-TEST
ZERO-g ADJUST
COMMON
DC Response
Low Noise (1.0 mg/√Hz)
+X ZERO-g ADJUST
25k⍀
Low-Power Consumption (1.8 mA per Axis)
؎35 g, ؎50 g Ranges Available (for ؎125 g or ؎50 g
Contact Factory)
+V
S
ADXL269
SENSOR
AMP
DEMODULATOR
FILTER
V
V
(+X)
(–X)
–
+
Surface Mount Package Available
OUT
5k⍀
5k⍀
V
2
S
OSCILLATOR
AMP
GENERAL DESCRIPTION
FILTER
OUT
SENSOR
The ADXL76, ADXL276, and ADXL269 family of products are
the third generation surface micromachined iMEMS accelero-
meters from Analog Devices with enhanced performance and lower
cost. Designed for use in front and side impact airbag applica-
tions, these products also provide complete cost-effective solutions
useful for a wide variety of other applications.
DEMODULATOR
25k⍀
+
–
SELF-TEST
–X ZERO-g ADJUST
COMMON
Y ZERO-g ADJUST
25k⍀
The ADXL276 is a monolithic two-axis (XY) version of the
ADXL76 with the sensor axes orthogonal (90°) to each other
and in the plane of the chip. It can be used for sensing crashes in
the front or side of the vehicle and can be used to determine the
angle of impact. The ADXL269 is a monolithic two-axis (+X/–X)
version of the ADXL76 with the sensor axes arranged in anti-
parallel orientation (180°) to provide redundancy and elimination
of the need for an external mechanical safing/arming sensor.
+V
ADXL276
S
AMP
DEMODULATOR
FILTER
V
V
OUT (Y)
5k⍀
5k⍀
V
2
S
OSCILLATOR
AMP
FILTER
OUT (X)
The ADXL76, ADXL269, and ADXL276 are temperature stable
and accurate over the automotive temperature range, with a self-
test feature that fully exercises all the mechanical and electrical
elements of the sensor with a digital signal applied to a single pin.
SENSOR
DEMODULATOR
25k⍀
SELF-TEST
X ZERO-g ADJUST
COMMON
i
MEMS is a registered trademark of Analog Devices, Inc.
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
Fax: 781/326-8703
World Wide Web Site: http://www.analog.com
© Analog Devices, Inc., 2000