Accelerometer Products

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Accelerometer Products What Is an Accelerometer and When Do You Use One?

MOTION INPUT 5% 5% Tilt Inertial Acceleration Shock and Vibration ACCELEROMETER Analog Output Digital Output To

the Earth s gravity ( static acceleration ).

Analog Devices accelerometers are more integrated and measure tilt at a higher bandwidth (up to 200 Hz) than the

Accelerometers Measure g To sell accelerometers, it is important to understand the concept of g, the unit that

Here s a brief guide to some relative g measurements.

experiences 1 g of acceleration) 0-2 g The acceleration range experienced when a human moves, for example, walking

would experience if you dropped it from 3 feet high onto a concrete floor 10,000 g The acceleration your laptop

sourceless measurement of velocity or distance or force.

1 Accelerometer Products What Is an Accelerometer and When Do You Use One? An accelerometer is a sensor which converts an acceleration from motion or gravity to an electrical signal. MOTION INPUT 5% 5% Tilt Inertial Acceleration Shock and Vibration ACCELEROMETER Analog Output Digital Output To measure tilt or inclination: Accelerometers can detect a change in tilt because they can measure and account for the Earth s gravity ( static acceleration ). They are used for applications such as car alarms, game joysticks and patient activity monitors. Analog Devices accelerometers are more integrated and measure tilt at a higher bandwidth (up to 200 Hz) than the more common liquid tilt sensors (1 Hz). Accelerometers Measure g To sell accelerometers, it is important to understand the concept of g, the unit that measures the earth s gravitational pull. Resolution is the minimum amount of g s a device can measure. Here s a brief guide to some relative g measurements. 1 g The acceleration exerted by the Earth s gravity on an object (for example, a laptop sitting on your desk experiences 1 g of acceleration) 0-2 g The acceleration range experienced when a human moves, for example, walking 5-30 g The acceleration experienced by the driver in a typical car crash g The acceleration your laptop would experience if you dropped it from 3 feet high onto a concrete floor 10,000 g The acceleration your laptop would experience if you shot it from a cannon To measure inertial forces: An accelerometer can serve as a sourceless measurement of velocity or distance or force. It can do this because acceleration integrated over time equals the speed an object is going; speed integrated over time results in distance. Inertial force applications include airbag crash sensors, car navigation systems and elevator control. To measure shock or vibration: Accelerometers can be used to measure vibrations, for example, from rotating equipment or earthquakes. Accelerometers have long been used to measure the health or condition of machinery to predict bearing failure.

2 What Types of Accelerometer Products Does ADI Offer? LOW G ACCELEROMETERS measure accelerations less than 10 g. For example, many popular applications such as tilt and motion measurement typically require a full scale of just 1 g. The ADXL202 is excellent for such low g applications as car alarms, earthquake detection or sports accessories. The ADXL210 is similar to the ADXL202, but its extended measurement range to 10 g makes it ideal for appliance vibration control and event recording in vehicle fleet management. The ADXL105 is an improved replacement of the now obsolete ADXL05, with a resolution of 2 mg or better for a measurement range of 5 g. This part is well suited for machine condition monitoring, car navigation systems or accurate tilt sensing. Design in Product ADXL202 ADXL210 ADXL105 Features 2 axis, 2 g full scale with 5 mg resolution, Analog or PWM output 2 axis, 10 g full scale with 5 mg resolution, Analog or PWM output 1 axis, 5 g full scale, with 2 mg resolution, Analog output 10 khz bandwidth Temperature sensor, Uncommitted amplifier Target markets Tilt/Inclination sensing Motion detection Car alarms Sporting goods Appliances vibration sensing Event recording Fleet monitoring Earthquake detection Disk drive arrays Machine condition monitoring Competition Liquid tilt sensors by Frederick s or Spectron have poor performance and lack integration More expensive electromechanical accelerometers VTI Hamlin offers a low g inclinometer but their two-chip, bulk micromachined approach can be prohibitively expensive for dual axis measurement.

3 Accelerometer Products HIGH G ACCELEROMETERS measure accelerations greater than 10 g. With measurement ranges of 50 or 100 g, these parts are typically used for shock, vibration or inertial measurements. The ADXL150/250 works well in shipping recorders, and can be used to monitor motors, pumps, or compressors. The ADXL190 can measure up to 100 g, making it ideal for certain machine condition monitoring applications, and for military fuse, safe and arm applications. Design in Product ADXL150 ADXL250 ADXL190 Features 1 axis, 50 g full scale with 10 mg resolution, wide dynamic range Analog output 2 axis, 50 g full scale with 10 mg resolution, wide dynamic range Analog output 1 axis, 100 g full scale, with 40 mg resolution, Analog output Target markets Vibration measurement Shock detection Machine condition monitoring Fleet monitoring Event recording Vibration measurement Shock detection Machine condition monitoring Fleet monitoring Event recording Same as above Military fuse, safe and arm Competition Motorola s 40 g sensor has inferior performance and higher prices. Bosch also makes 50 g accelerometers, but they target the automotive safety applications (airbags) almost exclusively. SINGLE AND DUAL AXIS ACCELEROMETERS Most applications require more than one axis of sensitivity, for example forward/backward, lateral or up/down motions (think about something tilting). Analog Devices provides both single and dual axis version accelerometers. Just like dual op-amps, a dual axis part is less expensive per axis than a single.

4 Selling Tips To help select the best accelerometer for your customer s application, ask your customer: 1. Do you wish to measure tilt, vibration or inertial forces? 2. What is the largest signal you need to measure in g s? 3. What is the smallest signal you need to be able to resolve? 4. What is the fastest signal you need to measure? 5. How many axes do you need to measure? Then, use the charts below to find the best ADI accelerometer for the job. 5% Tilt Inertial Vibration g range 1 g < 2 g < 10 g <50 g > 50 g < 2 g < 10 g <50 g >50 g ADXL202 ADXL202 ADXL210 ADXL202 ADXL210 Single Axis ADXL150 NA ADXL150 ADXL190 ADXL105 ADXL105 ADXL150 ADXL105 ADXL150 ADXL210 ADXL210 Dual Axis ADXL202 ADXL202 ADXL250 NA ADXL202 ADXL250 NA ADXL250 ADXL250 Use the ADXL202 For g ranges < 2 g and resolutions below 10 mg. Use the ADXL210 For g ranges <10 g and resolutions below 10 mg. Use the ADXL190 For g ranges to 100 g. Use the ADXL105 For g ranges <5 g, resolutions below 5 mg and bandwidth to 10 khz Use the ADXL150/250 For g ranges to 50 g, resolution to 10 mg, and bandwidth to 1 khz Model Max g Resolution Bandwidth # Axes Temp range Ic (Typ) Vdd Description 1.3 ma Precision, single axis 5 g ADXL105 5 g 2 mg 10 KHz 1 Com, Ind 2.7 V - 5 V at 2.7 V with temp sensor and analog output ADXL202 2 g 5 mg 5 KHz 2 Com, Ind 0.6 ma 3 V - 5 V ADXL g 5 mg 5 KHz 2 Com, Ind 0.6 ma 3 V - 5 V ADXL g 10 mg 1 KHz 1 Com, Ind 1.8 ma 4 V - 5 V ADXL g 10 mg 1 KHz 2 Com, Ind 3.5 ma 4 V - 5 V ADXL g 40 mg 400 Hz 1 Ind 2.0 ma 5 V Low cost dual axis 2 g with digital output Low cost dual axis 10 g with digital output Wide dynamic range 50 g with analog output Wide dynamic range 50 g with analog output, dual axis Low cost single axis 100 g with analog output

5 Accelerometer Products Who Needs Accelerometer Products? There are hundreds of applications in almost every industry. Market/End Product Application Type Recommended ADI Product My Customers Are: CONSUMER Car alarms Tilt and Shock ADXL202 Remote controls Tilt ADXL202 Navigation/GPS Inertial ADXL202, ADXL105 Appliance vibration control Vibration ADXL210, ADXL105 Sporting goods TIlt and Inertial ADXL202, ADXL150/250 PDA Tilt ADXL202 Smart pens Tilt ADXL202 COMPUTER/COMMUNICATION Read drives Vibration and Inertial ADXL202, ADXL105 Optical drives Vibration and Inertial ADXL202, ADXL105 Computer peripherals Tilt ADXL202 Antenna steering Tilt ADXL202 Head mounted displays Tilt ADXL202 INDUSTRIAL Earthquake-actuated safety mechanisms Vibration and Shock ADXL202, ADXL105 Elevator control Inertial ADXL202 Data recorders Shock and Inertial ADXL202 Shipping recorders Shock ADXL150/250 Motor/pump/compressor monitoring Vibration ADXL150/250 Vehicle fleet monitors Shock, Inertial ADXL202, ADXL210 Motion control Vibration, Inertial ADXL202 Robotics Tilt and Inertial ADXL202 MILITARY Safety and arming Inertial ADXL150, ADXL190 Fusing Inertial and Shock ADXL150/250, ADXL190 Guidance and control Inertial ADXL202 Condition monitoring Vibration ADXL202, ADXL150/250, ADXL105 Personal navigation Inertial ADXL202, ADXL105 MEDICAL Patient monitoring/emergency call Tilt, Inertial ADXL202 Patient activity and orientation Tilt, Inertial ADXL202 Hospital bed control Tilt ADXL202 Holter monitors Vibration ADXL202 Physical therapy Tilt, Vibration ADXL202 Prosthetics Inertial ADXL202

6 Analog Speak... Here s a guide to some of the questions customers will ask about accelerometers. If Your Customer Says... They Mean... You Can Respond... How do your What technology do your accelerometers use? ADI s devices are solid state accelerometers built accelerometers work? using surface micromachining techniques. They are MEMS, or Micro Electro Mechanical Systems. Do you need external What is the output of the accelerometer and ADI accelerometers integrate all the signal condisignal conditioning does it need further processing? tioning circuitry required to translate an acceleracircuitry? tion into an electrical signal. The ADXL202 even eliminates the need for an ADC, and interfaces directly to a microcontroller. What is the bandwidth What acceleration signal frequencies can you measure? All ADI accelerometers can measure accelerations of your products? (Vibrations can be high frequency accelerations with frequency ranges from 0 Hz to 1 KHz, unlike while gravity is a static or 0 Hz acceleration) piezoelectric or piezofilm accelerometers which cannot measure a 0 Hz acceleration. The ADXL105 can measure accelerations up to 10 khz. How many g s can What is the device s full scale acceleration range The ADXL150 and ADXL250 can measure up to you measure? in g s? +50 g and still resolve down to 10 mg of acceleration. The ADXL202 can measure up to 2 g and the ADXL190 up to 100 g. I only need to measure A 2 g full scale measurement range is sufficient, All ADI devices are guaranteed to withstand at least 2 g but the accelerometer but the device must still operate after being 1000 g unpowered (some 2000 g), and 500 g powered. must withstand shocks submitted to accelerations of 500 g. Our ADXL50 was still operating after being shot of up to 500 g. from a canon, withstanding over 10,000 g of acceleration. I need to measure I need an accelerometer that can resolve down With proper bandwidth control using simple low 10 mg of acceleration. to 10 mg, a rather small acceleration. low pass filtering techniques, the ADXL202 can resolve down to less than 5 mg. I need to be able to I need to use an accelerometer as a tilt measurement The ADXL202, a low g accelerometer, can resolve measure 1 degree of tilt. device which can resolve down to 1 degree of tilt. down to less than a third of a degree of tilt. I need a tri-axial. I need to measure acceleration in the three axes, ADI offers both single and dual axis devices which x, y and z. can be combined to form tri-axial sensors. Or you can contact one of our repackagers who can put ADI accelerometers in a tri-axial module for you.

7 Accelerometer Products Design Support Tools To help your customers design with our accelerometers, ADI has developed a suite of design support tools which can be ordered or downloaded from LOW G ACCELEROMETERS ADXL202 ADXL202EB Evaluation Board. This simple board includes a dual axis ADXL202, the minimum number of external components required to operate the device, and provides access to supplies, outputs and self-test connections. ADXL202EB-232 Evaluation Kit. A microcontrollerbased ADXL202 board with RS-232 cable for PC datalogging and CD-ROM demonstration software. The board is also designed to accept a test socket and can work with the ADXL210. ADXL202 Interactive Designer. A step-by-step guide to designing the ADXL202 in your customer s application. This Excel spreadsheet calculates external component values and resolution performance given a set of input parameters. Reference Design. The firmware for an ADXL202 design using a Microchip 16C63 is provided for download. The reference design implements the scheme discussed in the article, Using the ADXL202 with a Microcontroller. HIGH G ACCELEROMETERS ADXL150 ADXL150EB Evaluation Board. This PCB includes a dual axis ADXL250, the minimum number of external components to operate the device, access to inputs and outputs, and a small area for application-specific breadboarding requirements. ADXL150EM-1/EM-3 Evaluation Modules. These are complete, single and multi axis acceleration measurement systems in a low cost package. All that is needed to use these modules is a 5 V power supply. ADXL250 ADXL250EB Evaluation Board. This PCB includes a dual axis ADXL250, the minimum number of external components to operate the device, access to inputs and outputs, and a small area for application-specific breadboarding requirements. ADXL190 ADXL190EM-1 Evaluation Module. Similar to the ADXL150 evaluation module but with the ADXL190 accelerometer. ADXL210 ADXL210EB Evaluation Board. Similar to the ADXL202EB but uses an ADXL210. ADXL105 ADXL105EB Evaluation Board. A simple board including an ADXL105. ADXL105EM-1/EM-3 Evaluation Modules. These are complete, single and multi axis acceleration measurement systems in a low cost package. All that is needed to use these modules is a 5 V power supply.

Where To Get More Information Accelerometer web page: http://www.analog.

com/distributor ADI Faxback system: 1-800-446-6212 Datasheet Faxback Code ADXL105 2595 ADXL150/250 2060 ADXL190 2143 ADXL202/210 2458 ADI CD-ROM catalog ADI Short Form

8 Where To Get More Information Accelerometer web page: ADI Literature Center: ADI Faxback system: Datasheet Faxback Code ADXL ADXL150/ ADXL ADXL202/ ADI CD-ROM catalog ADI Short Form Designers Guide sensors section This primer can also be downloaded from ADI s Distributor Corner ( One Technology Way P.O. Box 9106 Norwood, Massachusetts U.S.A. All trademarks are properties of their respective holders C3341a-12-3/00 (rev. A) Copyright 2000 Analog Devices, Inc. Contributors: Jim Doscher, Christophe Lemaire, Mimi Pichey

Low Cost 100 g Single Axis Accelerometer with Analog Output ADXL190*

Low Cost 100 g Single Axis Accelerometer with Analog Output ADXL190* a FEATURES imems Single Chip IC Accelerometer 40 Milli-g Resolution Low Power ma 400 Hz Bandwidth +5.0 V Single Supply Operation 000 g Shock Survival APPLICATIONS Shock and Vibration Measurement Machine