Datasheet ADXL213 (Analog Devices)

Low Cost ±1.2 g Dual Axis Accelerometer ADXL213 FEATURES GENERAL DESCRIPTION Dual axis accelerometer on a single IC chip
The ADXL213 is a low cost, low power, complete dual axis
5 mm × 5 mm × 2 mm LCC package
accelerometer with signal conditioned, duty cycle modulated
1 mg resolution at 60 Hz
outputs, all on a single monolithic IC. The ADXL213 measures
Low power: 700 μA at VS = 5 V (typical)
acceleration with a full-scale range of ±1.2 g (typical). The
High zero g bias stability
ADXL213 can measure both dynamic acceleration (e.g.,
High sensitivity accuracy
vibration) and static acceleration (e.g., gravity).
Pulse width modulated digital outputs X and Y axes aligned to within 0.1° (typical)
The outputs are digital signals whose duty cycles (ratio of pulse
BW adjustment with a single capacitor
width to period) are proportional to acceleration (30%/g). The
Single-supply operation
duty cycle outputs can be directly measured by a microcontrol-
3500 g shock survival
ler without an A/D converter or glue logic.
Qualified for automotive applications
Innovative design techniques are used to ensure high zero g bias stability (typically better than 0.25 mg/°C), as well as tight sensi-
APPLICATIONS
tivity stability (typically better than 50 ppm/°C).
Automotive tilt alarms Data projectors
The typical noise floor is 160 μg/√Hz, allowing signals below
Navigation
1 mg (0.06° of inclination) to be resolved in tilt sensing applica-
Platform stabilization/leveling
tions using narrow bandwidths (<60 Hz).
Alarms and motion detectors High accuracy, 2-axis tilt sensing
The user selects the bandwidth of the accelerometer using capacitors CX and CY at the XFILT and YFILT pins. Bandwidths of 0.5 Hz to 250 Hz may be selected to suit the application. The ADXL213 is available in a 5 mm × 5 mm × 2 mm, 8-pad hermetic LCC package.
FUNCTIONAL BLOCK DIAGRAM +VS CY +V Y S FILT ADXL213 32k
Ω
OUTPUT YOUT C AMP DC AC DEMOD DCM AMP OUTPUT XOUT SENSOR AMP 32k
Ω
COM ST XFILT T2 CX RSET T2 T1 A(g ) = (T1/T2 – 0.5)/30% 0g = 50% DUTY CYCLE T2(s) = R
04742-0-001
SET/125M
Ω Figure 1.
Rev. A 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. or otherwise under any patent or patent rights of Analog Devices. Trademarks and Tel: 781.329.4700 www.analog.com registered trademarks are the property of their respective owners. Fax: 781.326.8703© 2004–2010 Analog Devices, Inc. All rights reserved.
Document Outline REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION PERFORMANCE APPLICATIONS POWER SUPPLY DECOUPLING SETTING THE BANDWIDTH USING CX AND CY SELF TEST DESIGN TRADE-OFFS FOR SELECTING FILTER CHARACTERISTICS: THE NOISE/BW TRADE-OFF USING THE ADXL213 WITH OPERATING VOLTAGES OTHER THAN 5 V USING THE ADXL213 AS A DUAL-AXIS TILT SENSOR Dual-Axis Tilt Sensor: Converting Acceleration to Tilt PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS OUTLINE DIMENSIONS ESD CAUTION ORDERING GUIDE AUTOMOTIVE PRODUCTS