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 A at V = 5 V (typical) S 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 The outputs are digital signals whose duty cycles (ratio of pulse X and Y axes aligned to within 0.1 (typical) width to period) are proportional to acceleration (30%/g). The BW adjustment with a single capacitor duty cycle outputs can be directly measured by a microcontrol- Single-supply operation ler without an A/D converter or glue logic. 3500 g shock survival 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 g/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 The user selects the bandwidth of the accelerometer using High accuracy, 2-axis tilt sensing capacitors C and C at the X and Y pins. Bandwidths of X Y FILT FILT 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 +V S C Y +V Y FILT S ADXL213 32k OUTPUT Y OUT AMP C DC AC DEMOD DCM AMP OUTPUT X OUT AMP SENSOR 32k COM ST X T2 FILT C R X SET T2 T1 A(g) = (T1/T2 0.5)/30% 0g = 50% DUTY CYCLE T2(s) = R /125M SET 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. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Specifications subject to change without notice. No license is granted by implication Tel: 781.329.4700 www.analog.com or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Fax: 781.326.8703 20042010 Analog Devices, Inc. All rights reserved. 04742-0-001ADXL213 TABLE OF CONTENTS Revision History ............................................................................... 2 Design Trade-Offs for Selecting Filter Characteristics: The Noise/BW Trade-Off............................................................................. 9 Specif icat ions ..................................................................................... 3 Using the ADXL213 with Operating Voltages Other than 5 V .. 10 Absolute Maximum Ratings ............................................................ 4 Using the ADXL213 as a Dual-Axis Tilt Sensor ............................ 10 Typical Performance Characteristics ............................................. 5 Pin Configurations and Functional Descriptions ...................... 11 Theory of Operation ........................................................................ 8 Outline Dimensions ....................................................................... 12 Performance ........................................................................................... 8 ESD Caution ......................................................................................... 12 Applications ....................................................................................... 9 Ordering Guide .................................................................................... 12 Power Supply Decoupling .................................................................... 9 Automotive Products .......................................................................... 12 Setting the Bandwidth Using CX and CY ........................................... 9 Self Test .................................................................................................... 9 REVISION HISTORY 8/10Rev. 0 to Rev. A Added Automotive line to Features Section ................................. 1 Updated Outline Dimensions ....................................................... 12 Changes to Ordering Guide .......................................................... 12 Added Automotive Products Section .......................................... 12 4/04Revision 0: Initial Version Rev. A Page 2 of 12