Single-Axis, High-g,
iMEMS
®
Accelerometers
ADXL78
Rev. B
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FEATURES
Complete acceleration measurement system on a single
monolithic IC
Available in ±35 g, ±50 g, or ±70 g output full-scale ranges
Full differential sensor and circuitry for high resistance
to EMI/RFI
Environmentally robust packaging
Complete mechanical and electrical self-test on
digital command
Output ratiometric to supply
Sensitive axes in the plane of the chip
High linearity (0.2% of full scale)
Frequency response down to dc
Low noise
Low power consumption (1.3 mA)
Tight sensitivity tolerance and 0 g offset capability
Largest available prefilter clipping headroom
400 Hz, 2-pole Bessel filter
Single-supply operation
Compatible with Sn/Pb and Pb-free solder processes
Qualified for automotive applications
APPLICATIONS
Vibration monitoring and control
Vehicle collision sensing
Shock detection
GENERAL DESCRIPTION
The ADXL78 is a low power, complete single-axis accelerometer
with signal conditioned voltage outputs that are on a single
monolithic IC. This product measures acceleration with a full-
scale range of ±35 g, ±50 g, or ±70 g (minimum). It can also
measure both dynamic acceleration (vibration) and static
acceleration (gravity).
The ADXL78 is the fourth-generation surface micromachined
iMEMS® accelerometer from ADI with enhanced performance
and lower cost. Designed for use in front and side impact airbag
applications, this product also provides a complete cost-
effective solution useful for a wide variety of other applications.
The ADXL78 is 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.
The ADXL78 is available in a 5 mm × 5 mm × 2 mm,
8-terminal ceramic LCC package.
FUNCTIONAL BLOCK DIAGRAM
05368-001
ADXL78
V
DD
V
S
V
DD2
DIFFERENTIAL
SENSOR
EXC
DEMOD
AMP
X
OUT
400Hz
BESSEL
FILTER
TIMING
GENERATOR
SELF-TEST
Figure 1.
