ADXL335BCPZ

**Small, Low Power, 3-Axis ±3** _**g**_ **Accelerometer** 

**ADXL335** 

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## **FEATURES** 

## **3-axis sensing** 

**Small, low profile package** 

**4 mm × 4 mm × 1.45 mm LFCSP Low power : 350 μA (typical) Single-supply operation: 1.8 V to 3.6 V 10,000** _**g**_ **shock survival** 

**Excellent temperature stability BW adjustment with a single capacitor per axis RoHS/WEEE lead-free compliant** 

## **APPLICATIONS** 

**Cost sensitive, low power, motion- and tilt-sensing** 

**applications Mobile devices Gaming systems Disk drive protection Image stabilization Sports and health devices** 

## **GENERAL DESCRIPTION** 

The ADXL335 is a small, thin, low power, complete 3-axis accelerometer with signal conditioned voltage outputs. The product measures acceleration with a minimum full-scale range of ±3 _g_ . It can measure the static acceleration of gravity in tilt-sensing applications, as well as dynamic acceleration resulting from motion, shock, or vibration. 

The user selects the bandwidth of the accelerometer using the CX, CY, and CZ capacitors at the XOUT, YOUT, and ZOUT pins. Bandwidths can be selected to suit the application, with a range of 0.5 Hz to 1600 Hz for the X and Y axes, and a range of 0.5 Hz to 550 Hz for the Z axis. 

The ADXL335 is available in a small, low profile, 4 mm × 4 mm × 1.45 mm, 16-lead, plastic lead frame chip scale package (LFCSP_LQ). 

## **FUNCTIONAL BLOCK DIAGRAM** 

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+3V<br>VS<br>ADXL335 ~32kΩ XOUT<br>OUTPUT AMP<br>CX<br>3-AXIS<br>SENSOR<br>~32kΩ YOUT<br>CDC AC AMP DEMOD OUTPUT AMP<br>CY<br>~32kΩ ZOUT<br>OUTPUT AMP<br>CZ<br>COM ST<br>Figure 1.<br>07808-001<br>**----- End of picture text -----**<br>


**Rev. B** 

**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 or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners.** 

**One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2009–2010 Analog Devices, Inc. All rights reserved.** 

## **ADXL335** 

## **TABLE OF CONTENTS** 

Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Absolute Maximum Ratings ............................................................ 4 ESD Caution .................................................................................. 4 Pin Configuration and Function Descriptions ............................. 5 Typical Performance Characteristics ............................................. 6 Theory of Operation ...................................................................... 10 Mechanical Sensor ...................................................................... 10 

Performance ................................................................................ 10 Applications Information .............................................................. 11 Power Supply Decoupling ......................................................... 11 Setting the Bandwidth Using CX, CY, and CZ .......................... 11 Self-Test ....................................................................................... 11 Design Trade-Offs for Selecting Filter Characteristics: The Noise/BW Trade-Off .................................................................. 11 Use with Operating Voltages Other Than 3 V ........................... 12 Axes of Acceleration Sensitivity ............................................... 12 Layout and Design Recommendations ................................... 13 Outline Dimensions ....................................................................... 14 Ordering Guide .......................................................................... 14 

## **REVISION HISTORY** 

**1/10—Rev. A to Rev. B** Changes to Figure 21 ........................................................................ 9 

**7/09—Rev. 0 to Rev. A** Changes to Figure 22 ........................................................................ 9 Changes to Outline Dimensions ................................................... 14 

**1/09—Revision 0: Initial Version** 

Rev. B | Page 2 of 16 

**ADXL335** 

## **SPECIFICATIONS** 

TA = 25°C, VS = 3 V, CX = CY = CZ = 0.1 μF, acceleration = 0 _g_ , unless otherwise noted. All minimum and maximum specifications are guaranteed. Typical specifications are not guaranteed. 

**Table 1.** 

|**Table 1.**|||||
|---|---|---|---|---|
|**Parameter**|**Conditions**|**Min**|**Typ**<br>**Max**|**Unit**|
|SENSOR INPUT<br>Measurement Range<br>Nonlinearity<br>Package Alignment Error<br>Interaxis Alignment Error<br>Cross-Axis Sensitivity1|Each axis<br>% of full scale|±3|±3.6<br>±0.3<br>±1<br>±0.1<br>±1|_g_<br>%<br>Degrees<br>Degrees<br>%|
|SENSITIVITY (RATIOMETRIC)2<br>Sensitivity at XOUT, YOUT, ZOUT<br>SensitivityChange Due to Temperature3|Each axis<br>VS= 3 V<br>VS= 3 V|270|300<br>330<br>±0.01|mV/_g_<br>%/°C|
|ZERO_g_BIAS LEVEL (RATIOMETRIC)<br>0_g_Voltage at XOUT, YOUT<br>0_g_Voltage at ZOUT<br>0_g_Offset vs. Temperature|VS= 3 V<br>VS= 3 V|1.35<br>1.2|1.5<br>1.65<br>1.5<br>1.8<br>±1|V<br>V<br>m_g_/°C|
|NOISE PERFORMANCE<br>Noise Density XOUT, YOUT<br>Noise Density ZOUT|||150<br>300|μ_g_/√Hz rms<br>μ_g_/√Hz rms|
|FREQUENCY RESPONSE4<br>Bandwidth XOUT, YOUT5<br>Bandwidth ZOUT5<br>RFILTTolerance<br>Sensor Resonant Frequency|No external filter<br>No external filter||1600<br>550<br>32 ± 15%<br>5.5|Hz<br>Hz<br>kΩ<br>kHz|
|SELF-TEST6<br>Logic Input Low<br>Logic Input High<br>ST Actuation Current<br>Output Change at XOUT<br>Output Change at YOUT<br>Output Change at ZOUT|Self-Test 0 to Self-Test 1<br>Self-Test 0 to Self-Test 1<br>Self-Test 0 to Self-Test 1|−150<br>+150<br>+150|+0.6<br>+2.4<br>+60<br>−325<br>−600<br>+325<br>+600<br>+550<br>+1000|V<br>V<br>μA<br>mV<br>mV<br>mV|
|OUTPUT AMPLIFIER<br>Output Swing Low<br>Output SwingHigh|No load<br>No load||0.1<br>2.8|V<br>V|
|POWER SUPPLY<br>Operating Voltage Range<br>Supply Current<br>Turn-On Time7|VS= 3 V<br>No external filter|1.8|3.6<br>350<br>1|V<br>μA<br>ms|
|TEMPERATURE<br>Operating Temperature Range||−40|+85|°C|



1 Defined as coupling between any two axes. 

2 Sensitivity is essentially ratiometric to VS. 

3 Defined as the output change from ambient-to-maximum temperature or ambient-to-minimum temperature. 

4 Actual frequency response controlled by user-supplied external filter capacitors (CX, CY, CZ). 

5 Bandwidth with external capacitors = 1/(2 × π × 32 kΩ × C). For CX, CY = 0.003 μF, bandwidth = 1.6 kHz. For CZ = 0.01 μF, bandwidth = 500 Hz. For CX, CY, CZ = 10 μF, bandwidth = 0.5 Hz. 

> 6 Self-test response changes cubically with VS. 

> 7 Turn-on time is dependent on CX, CY, CZ and is approximately 160 × CX or CY or CZ + 1 ms, where CX, CY, CZ are in microfarads (μF). 

Rev. B | Page 3 of 16 

## **ADXL335** 

## **ABSOLUTE MAXIMUM RATINGS** 

## **Table 2.** 

**Parameter Rating** Acceleration (Any Axis, Unpowered) 10,000 _g_ Acceleration (Any Axis, Powered) 10,000 _g_ VS −0.3 V to +3.6 V All Other Pins (COM − 0.3 V) to (VS + 0.3 V) Output Short-Circuit Duration Indefinite (Any Pin to Common) Temperature Range (Powered) −55°C to +125°C Temperature Range (Storage) −65°C to +150°C 

Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. 

## **ESD CAUTION** 

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Rev. B | Page 4 of 16 

**ADXL335** 

## **PIN CONFIGURATION AND FUNCTION DESCRIPTIONS** 

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16 15 14 13<br>NC 1 ADXL335 12 XOUT<br>TOP VIEW<br>ST 2 (Not to Scale) 11 NC<br>+Y<br>COM 3 +Z 10 YOUT<br>NC 4 +X 9 NC<br>5 6 7 8<br>NC = NO CONNECT<br>NOTES<br>1. EXPOSED PAD IS NOT INTERNALLY<br>    CONNECTED BUT SHOULD BE SOLDERED<br>    FOR MECHANICAL INTEGRITY.<br>Figure 2. Pin Configuration<br>NC VS VS NC<br>COM COM COM ZOUT<br>07808-003<br>**----- End of picture text -----**<br>


**Table 3. Pin Function Descriptions** 

|**Pin No.**|**Mnemonic**|**Description**|
|---|---|---|
|1<br>2<br>3<br>4<br>5<br>6<br>7<br>8<br>9<br>10<br>11<br>12<br>13<br>14<br>15<br>16<br>EP|NC<br>ST<br>COM<br>NC<br>COM<br>COM<br>COM<br>ZOUT<br>NC<br>YOUT<br>NC<br>XOUT<br>NC<br>VS<br>VS<br>NC<br>Exposed Pad|No Connect.1<br>Self-Test.<br>Common.<br>No Connect.1<br>Common.<br>Common.<br>Common.<br>Z Channel Output.<br>No Connect.1<br>Y Channel Output.<br>No Connect.1<br>X Channel Output.<br>No Connect.1<br>Supply Voltage (1.8 V to 3.6 V).<br>Supply Voltage (1.8 V to 3.6 V).<br>No Connect.1<br>Not internallyconnected. Solder for mechanical integrity.|



1 NC pins are not internally connected and can be tied to COM pins, unless otherwise noted. 

Rev. B | Page 5 of 16 

## **ADXL335** 

## **TYPICAL PERFORMANCE CHARACTERISTICS** 

N > 1000 for all typical performance plots, unless otherwise noted. 

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50<br>40<br>30<br>20<br>10<br>0<br>1.42 1.44 1.46 1.48 1.50 1.52 1.54 1.56 1.58<br>OUTPUT (V)<br>% OF POPULATION<br>07808-005<br>**----- End of picture text -----**<br>


_Figure 3. X-Axis Zero_ g _Bias at 25°C, VS = 3 V_ 

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50<br>40<br>30<br>20<br>10<br>0<br>1.42 1.44 1.46 1.48 1.50 1.52 1.54 1.56 1.58<br>OUTPUT (V)<br>Figure 4. Y-Axis Zero  g  Bias at 25°C, VS = 3 V<br>25<br>20<br>15<br>10<br>5<br>0<br>1.42 1.44 1.46 1.48 1.50 1.52 1.54 1.56 1.58<br>OUTPUT (V)<br>Figure 5. Z-Axis Zero  g  Bias at 25°C, VS = 3 V<br>% OF POPULATION<br>07808-006<br>% OF POPULATION<br>07808-007<br>**----- End of picture text -----**<br>


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40<br>30<br>20<br>10<br>0<br>–0.40 –0.38 –0.36 –0.34 –0.32 –0.30 –0.28 –0.26<br>VOLTS (V)<br>Figure 6. X-Axis Self-Test Response at 25°C, VS = 3 V<br>50<br>40<br>30<br>20<br>10<br>0<br>0.26 0.28 0.30 0.32 0.34 0.36 0.38 0.40<br>VOLTS (V)<br>Figure 7. Y-Axis Self-Test Response at 25°C, VS = 3 V<br>40<br>30<br>20<br>10<br>0<br>0.48 0.50 0.52 0.54 0.56 0.58 0.60 0.62<br>VOLTS (V)<br>Figure 8. Z-Axis Self-Test Response at 25°C, VS = 3 V<br>% OF POPULATION<br>07808-008<br>% OF POPULATION<br>07808-009<br>% OF POPULATION<br>07808-010<br>**----- End of picture text -----**<br>


Rev. B | Page 6 of 16 

**ADXL335** 

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30<br>25<br>20<br>15<br>10<br>5<br>0<br>–3.0 –2.5 –2.0 –1.5 –1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5 3.0<br>TEMPERATURE COEFFICIENT (m g /°C)<br>Figure 9. X-Axis Zero  g  Bias Temperature Coefficient, VS = 3 V<br>% OF POPULATION<br>07808-011<br>**----- End of picture text -----**<br>


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40<br>30<br>20<br>10<br>0<br>–3.0 –2.5 –2.0 –1.5 –1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5 3.0<br>TEMPERATURE COEFFICIENT (m g /°C)<br>% OF POPULATION<br>07808-012<br>**----- End of picture text -----**<br>


_Figure 10. Y-Axis Zero_ g _Bias Temperature Coefficient, VS = 3 V_ 

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20<br>15<br>10<br>5<br>0<br>–7 –6 –5 –4 –3 –2 –1 0 1 2 3 4 5 6 7<br>TEMPERATURE COEFFICIENT (m g /°C)<br>Figure 11. Z-Axis Zero  g  Bias Temperature Coefficient, VS = 3 V<br>% OF POPULATION<br>07808-013<br>**----- End of picture text -----**<br>


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1.55<br>N = 8<br>1.54<br>1.53<br>1.52<br>1.51<br>1.50<br>1.49<br>1.48<br>1.47<br>1.46<br>1.45<br>–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90 100<br>TEMPERATURE (°C)<br>Figure 12. X-Axis Zero  g  Bias vs. Temperature—<br>Eight Parts Soldered to PCB<br>1.55<br>N = 8<br>1.54<br>1.53<br>1.52<br>1.51<br>1.50<br>1.49<br>1.48<br>1.47<br>1.46<br>1.45<br>–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90 100<br>TEMPERATURE (°C)<br>Figure 13. Y-Axis Zero  g  Bias vs. Temperature—<br>Eight Parts Soldered to PCB<br>1.50<br>N = 8<br>1.48<br>1.46<br>1.44<br>1.42<br>1.40<br>1.38<br>1.36<br>1.34<br>1.32<br>1.30<br>–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90 100<br>TEMPERATURE (°C)<br>Figure 14. Z-Axis Zero  g  Bias vs. Temperature—<br>Eight Parts Soldered to PCB<br>OUTPUT (V)<br>07808-014<br>OUTPUT (V)<br>07808-015<br>OUTPUT (V)<br>07808-016<br>**----- End of picture text -----**<br>


Rev. B | Page 7 of 16 

## **ADXL335** 

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20<br>15<br>10<br>5<br>0<br>0.285 0.288 0.291 0.294 0.297 0.300 0.303 0.306 0.309 0.312 0.315<br>SENSITIVITY (V/ g )<br>% OF POPULATION<br>07808-017<br>**----- End of picture text -----**<br>


_Figure 15. X-Axis Sensitivity at 25°C, VS = 3 V_ 

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25<br>20<br>15<br>10<br>5<br>0<br>0.285 0.288 0.291 0.294 0.297 0.300 0.303 0.306 0.309 0.312 0.315<br>SENSITIVITY (V/ g )<br>% OF POPULATION<br>07808-018<br>**----- End of picture text -----**<br>


_Figure 16. Y-Axis Sensitivity at 25°C, VS = 3 V_ 

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25<br>20<br>15<br>10<br>5<br>0<br>0.285 0.288 0.291 0.294 0.297 0.300 0.303 0.306 0.309 0.312 0.315<br>SENSITIVITY (V/ g )<br>% OF POPULATION<br>07808-019<br>**----- End of picture text -----**<br>


_Figure 17. Z-Axis Sensitivity at 25°C, VS = 3 V_ 

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0.320<br>N = 8<br>0.315<br>0.310<br>0.305<br>0.300<br>0.295<br>0.290<br>0.285<br>0.280<br>–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90 100<br>TEMPERATURE (°C)<br>Figure 18. X-Axis Sensitivity vs. Temperature—<br>Eight Parts Soldered to PCB, VS = 3 V<br>0.320<br>N = 8<br>0.315<br>0.310<br>0.305<br>0.300<br>0.295<br>0.290<br>0.285<br>0.280<br>–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90 100<br>TEMPERATURE (°C)<br>Figure 19. Y-Axis Sensitivity vs. Temperature—<br>Eight Parts Soldered to PCB, VS = 3 V<br>0.320<br>N = 8<br>0.315<br>0.310<br>0.305<br>0.300<br>0.295<br>0.290<br>0.285<br>0.280<br>–40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90 100<br>TEMPERATURE (°C)<br>) g<br>SENSITIVITY (V/<br>07808-020<br>) g<br>SENSITIVITY (V/<br>07808-021<br>) g<br>SENSITIVITY (V/<br>07808-022<br>**----- End of picture text -----**<br>


_Figure 20. Z-Axis Sensitivity vs. Temperature— Eight Parts Soldered to PCB, VS = 3 V_ 

Rev. B | Page 8 of 16 

**ADXL335** 

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350<br>300<br>250<br>200<br>150<br>100<br>50<br>0<br>1.5 2.0 2.5 3.0 3.5 4.0<br>SUPPLY (V)<br>CURRENT (µA)<br>07808-023<br>**----- End of picture text -----**<br>


_Figure 21. Typical Current Consumption vs. Supply Voltage_ 

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CX = CY = CZ = 0.0047µF<br>CH4: ZOUT,<br>500mV/DIV<br>CH3: YOU T,<br>500mV/DIV<br>CH2: XOU T,<br>500mV/DIV<br>CH1: POWER,<br>1V/DIV<br>OUTPUTS ARE OF F SET FOR CLARITY<br>TIME (1ms/DIV) 07808-024<br>**----- End of picture text -----**<br>


_Figure 22. Typical Turn-On Time, VS = 3 V_ 

Rev. B | Page 9 of 16 

## **ADXL335** 

## **THEORY OF OPERATION** 

The ADXL335 is a complete 3-axis acceleration measurement system. The ADXL335 has a measurement range of ±3 _g_ minimum. It contains a polysilicon surface-micromachined sensor and signal conditioning circuitry to implement an open-loop acceleration measurement architecture. The output signals are analog voltages that are proportional to acceleration. The accelerometer can measure the static acceleration of gravity in tilt-sensing applications as well as dynamic acceleration resulting from motion, shock, or vibration. 

The sensor is a polysilicon surface-micromachined structure built on top of a silicon wafer. Polysilicon springs suspend the structure over the surface of the wafer and provide a resistance against acceleration forces. Deflection of the structure is measured using a differential capacitor that consists of independent fixed plates and plates attached to the moving mass. The fixed plates are driven by 180° out-of-phase square waves. Acceleration deflects the moving mass and unbalances the differential capacitor resulting in a sensor output whose amplitude is proportional to acceleration. Phase-sensitive demodulation techniques are then used to determine the magnitude and direction of the acceleration. 

The demodulator output is amplified and brought off-chip through a 32 kΩ resistor. The user then sets the signal bandwidth of the device by adding a capacitor. This filtering improves measurement resolution and helps prevent aliasing. 

## **MECHANICAL SENSOR** 

The ADXL335 uses a single structure for sensing the X, Y, and Z axes. As a result, the three axes’ sense directions are highly orthogonal and have little cross-axis sensitivity. Mechanical misalignment of the sensor die to the package is the chief source of cross-axis sensitivity. Mechanical misalignment can, of course, be calibrated out at the system level. 

## **PERFORMANCE** 

Rather than using additional temperature compensation circuitry, innovative design techniques ensure that high performance is built in to the ADXL335. As a result, there is no quantization error or nonmonotonic behavior, and temperature hysteresis is very low (typically less than 3 m _g_ over the −25°C to +70°C temperature range). 

Rev. B | Page 10 of 16 

**ADXL335** 

## **APPLICATIONS INFORMATION** 

## **POWER SUPPLY DECOUPLING** 

For most applications, a single 0.1 μF capacitor, CDC, placed close to the ADXL335 supply pins adequately decouples the accelerometer from noise on the power supply. However, in applications where noise is present at the 50 kHz internal clock frequency (or any harmonic thereof), additional care in power supply bypassing is required because this noise can cause errors in acceleration measurement. 

If additional decoupling is needed, a 100 Ω (or smaller) resistor or ferrite bead can be inserted in the supply line. Additionally, a larger bulk bypass capacitor (1 μF or greater) can be added in parallel to CDC. Ensure that the connection from the ADXL335 ground to the power supply ground is low impedance because noise transmitted through ground has a similar effect to noise transmitted through VS. 

## **SETTING THE BANDWIDTH USING CX, CY, AND CZ** 

The ADXL335 has provisions for band limiting the XOUT, YOUT, and ZOUT pins. Capacitors must be added at these pins to implement low-pass filtering for antialiasing and noise reduction. The equation for the 3 dB bandwidth is 

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or more simply 

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The tolerance of the internal resistor (RFILT) typically varies as much as ±15% of its nominal value (32 kΩ), and the bandwidth varies accordingly. A minimum capacitance of 0.0047 μF for CX, CY, and CZ is recommended in all cases. 

**Table 4. Filter Capacitor Selection, CX, CY, and CZ** 

|**Bandwidth (Hz)**|**Capacitor (μF)**|
|---|---|
|1<br>10<br>50<br>100<br>200<br>500|4.7<br>0.47<br>0.10<br>0.05<br>0.027<br>0.01|



## **SELF-TEST** 

The ST pin controls the self-test feature. When this pin is set to VS, an electrostatic force is exerted on the accelerometer beam. The resulting movement of the beam allows the user to test if the accelerometer is functional. The typical change in output is −1.08 _g_ (corresponding to −325 mV) in the X-axis, +1.08 _g_ (or +325 mV) on the Y-axis, and +1.83 _g_ (or +550 mV) on the Z-axis. This ST pin can be left open-circuit or connected to common (COM) in normal use. 

Never expose the ST pin to voltages greater than VS + 0.3 V. If this cannot be guaranteed due to the system design (for instance, if there are multiple supply voltages), then a low VF clamping diode between ST and VS is recommended. 

## **DESIGN TRADE-OFFS FOR SELECTING FILTER CHARACTERISTICS: THE NOISE/BW TRADE-OFF** 

The selected accelerometer bandwidth ultimately determines the measurement resolution (smallest detectable acceleration). Filtering can be used to lower the noise floor to improve the resolution of the accelerometer. Resolution is dependent on the analog filter bandwidth at XOUT, YOUT, and ZOUT. 

The output of the ADXL335 has a typical bandwidth of greater than 500 Hz. The user must filter the signal at this point to limit aliasing errors. The analog bandwidth must be no more than half the analog-to-digital sampling frequency to minimize aliasing. The analog bandwidth can be further decreased to reduce noise and improve resolution. 

The ADXL335 noise has the characteristics of white Gaussian noise, which contributes equally at all frequencies and is described in terms of μ _g_ /√Hz (the noise is proportional to the square root of the accelerometer bandwidth). The user should limit bandwidth to the lowest frequency needed by the application to maximize the resolution and dynamic range of the accelerometer. 

With the single-pole, roll-off characteristic, the typical noise of the ADXL335 is determined by 

_rms Noise_ = _Noise Density_ × ( _BW_ × 1.6 ) 

It is often useful to know the peak value of the noise. Peak-topeak noise can only be estimated by statistical methods. Table 5 is useful for estimating the probabilities of exceeding various peak values, given the rms value. 

**Table 5. Estimation of Peak-to-Peak Noise** 

|**Peak-to-Peak Value**|**% of Time That Noise Exceeds**<br>**Nominal Peak-to-Peak Value**|
|---|---|
|2 × rms<br>4 × rms<br>6 × rms<br>8 × rms|32<br>4.6<br>0.27<br>0.006|



Rev. B | Page 11 of 16 

## **ADXL335** 

## **USE WITH OPERATING VOLTAGES OTHER THAN 3 V** 

The ADXL335 is tested and specified at VS = 3 V; however, it can be powered with VS as low as 1.8 V or as high as 3.6 V. Note that some performance parameters change as the supply voltage is varied. 

The ADXL335 output is ratiometric, therefore, the output sensitivity (or scale factor) varies proportionally to the supply voltage. At VS = 3.6 V, the output sensitivity is typically 360 mV/ _g_ . At VS = 2 V, the output sensitivity is typically 195 mV/ _g_ . 

The zero _g_ bias output is also ratiometric, thus the zero _g_ output is nominally equal to VS/2 at all supply voltages. 

The output noise is not ratiometric but is absolute in volts; therefore, the noise density decreases as the supply voltage increases. This is because the scale factor (mV/ _g_ ) increases while the noise voltage remains constant. At VS = 3.6 V, the X-axis and Y-axis noise density is typically 120 μ _g_ /√Hz, whereas at VS = 2 V, the X-axis and Y-axis noise density is typically 270 μ _g_ /√Hz. 

Self-test response in _g_ is roughly proportional to the square of the supply voltage. However, when ratiometricity of sensitivity is factored in with supply voltage, the self-test response in volts is roughly proportional to the cube of the supply voltage. For example, at VS = 3.6 V, the self-test response for the ADXL335 is approximately −560 mV for the X-axis, +560 mV for the Y-axis, and +950 mV for the Z-axis. 

At VS = 2 V, the self-test response is approximately −96 mV for the X-axis, +96 mV for the Y-axis, and −163 mV for the Z-axis. 

The supply current decreases as the supply voltage decreases. Typical current consumption at VS = 3.6 V is 375 μA, and typical current consumption at VS = 2 V is 200 μA. 

## **AXES OF ACCELERATION SENSITIVITY** 

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AZ<br>AY<br>AX 07808-025<br>**----- End of picture text -----**<br>


_Figure 23. Axes of Acceleration Sensitivity; Corresponding Output Voltage Increases When Accelerated Along the Sensitive Axis._ 

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**----- Start of picture text -----**<br>
XOUT = –1 g<br>YOUT = 0 g<br>ZOUT = 0 g<br>TOP<br>GRAVITY<br>XOUT = 0 g XOUT = 0 g<br>YOUT = 1 g TOP TOP YOUT = –1 g<br>ZOUT = 0 g ZOUT = 0 g<br>TOP<br>XOUT = 1 g<br>YOUT = 0 g<br>ZOUT = 0 g<br>XOUT = 0 g XOUT = 0 g<br>YOUT = 0 g YOUT = 0 g<br>ZOUT = 1 g ZOUT = –1 g 07808-026<br>**----- End of picture text -----**<br>


_Figure 24. Output Response vs. Orientation to Gravity_ 

Rev. B | Page 12 of 16 

**ADXL335** 

## **LAYOUT AND DESIGN RECOMMENDATIONS** 

The recommended soldering profile is shown in Figure 25 followed by a description of the profile features in Table 6. The recommended PCB layout or solder land drawing is shown in Figure 26. 

**==> picture [242 x 129] intentionally omitted <==**

**----- Start of picture text -----**<br>
CRITICAL ZONE<br>TP tP TL TO TP<br>RAMP-UP<br>TL TSMAX tL<br>TSMIN<br>PREHEATtS RAMP-DOWN<br>t25°C TO PEAK<br>TIME<br>TEMPERATURE<br>07808-002<br>**----- End of picture text -----**<br>


_Figure 25. Recommended Soldering Profile_ 

**Table 6. Recommended Soldering Profile** 

|**Table 6. Recommended Soldering Profile**|||
|---|---|---|
|**Profile Feature**|**Sn63/Pb37**|**Pb-Free**|
|Average Ramp Rate (TLto TP)<br>Preheat<br>Minimum Temperature (TSMIN)<br>Maximum Temperature (TSMAX)<br>Time (TSMINto TSMAX)(tS)<br>TSMAXto TL<br>Ramp-Up Rate<br>Time Maintained Above Liquidous (TL)<br>Liquidous Temperature (TL)<br>Time (tL)<br>Peak Temperature (TP)<br>Time Within 5°C of Actual Peak Temperature (tP)<br>Ramp-Down Rate<br>Time 25°C to Peak Temperature|3°C/sec max<br>100°C<br>150°C<br>60 sec to 120 sec<br>3°C/sec max<br>183°C<br>60 sec to 150 sec<br>240°C + 0°C/−5°C<br>10 sec to 30 sec<br>6°C/sec max<br>6 minutes max|3°C/sec max<br>150°C<br>200°C<br>60 sec to 180 sec<br>3°C/sec max<br>217°C<br>60 sec to 150 sec<br>260°C + 0°C/−5°C<br>20 sec to 40 sec<br>6°C/sec max<br>8 minutes max|



**==> picture [243 x 177] intentionally omitted <==**

**----- Start of picture text -----**<br>
0.50 4<br>MAX<br>0.65 0.325<br>0.35<br>MAX<br>0.65<br>4<br>1.95<br>0.325<br>EXPOSED PAD IS NOT<br>INTERNALLY CONNECTED<br>BUT SHOULD BE SOLDERED<br>FOR MECHANICAL INTEGRITY.<br>1.95<br>DIMENSIONS SHOWN IN MILLIMETERS 07808-004<br>**----- End of picture text -----**<br>


_Figure 26. Recommended PCB Layout_ 

Rev. B | Page 13 of 16 

## **ADXL335** 

## **OUTLINE DIMENSIONS** 

**==> picture [308 x 181] intentionally omitted <==**

**----- Start of picture text -----**<br>
4.15<br>4.00 SQ 0.35<br>3.85 0.30<br>PIN 1 0.25<br>INDICATOR<br>13 16<br>0.65 12 1<br>BSC EXPOSEDPAD 2.55<br>2.40 SQ<br>2.25<br>9 4<br>8 5<br>0.55<br>TOP VIEW 0.50 BOTTOM VIEW 0.15 MAX<br>0.45<br>1.50 FOR PROPER CONNECTION OF<br>1.451.40 0.05 MAX THE EXPOSED PAD, REFER TOTHE PIN CONFIGURATION AND<br>0.02 NOM FUNCTION DESCRIPTIONS<br>COPLANARITY SECTION OF THIS DATA SHEET.<br>SEATING 0.08<br>PLANE 0.15 REF<br>COMPLIANT TO JEDEC STANDARDS MO-220-WGGD.<br>PIN 1<br>INDICATOR<br>**----- End of picture text -----**<br>


**==> picture [4 x 19] intentionally omitted <==**

**----- Start of picture text -----**<br>
051909-A<br>**----- End of picture text -----**<br>


_Figure 27. 16-Lead Lead Frame Chip Scale Package [LFCSP_LQ] 4 mm × 4 mm Body, 1.45 mm Thick Quad (CP-16-14) Dimensions shown in millimeters_ 

## **ORDERING GUIDE** 

|**Model1**|**Measurement Range **|**Specified Voltage**|**Temperature Range **|**Package Description**|**Package Option**|
|---|---|---|---|---|---|
|ADXL335BCPZ<br>ADXL335BCPZ–RL<br>ADXL335BCPZ–RL7<br>EVAL-ADXL335Z|±3_g_<br>±3_g_<br>±3_g_|3 V<br>3 V<br>3 V|−40°C to +85°C<br>−40°C to +85°C<br>−40°C to +85°C|16-Lead LFCSP_LQ<br>16-Lead LFCSP_LQ<br>16-Lead LFCSP_LQ<br>Evaluation Board|CP-16-14<br>CP-16-14<br>CP-16-14|



1 Z = RoHS Compliant Part. 

Rev. B | Page 14 of 16 

**ADXL335** 

## **NOTES** 

Rev. B | Page 15 of 16 

## **ADXL335** 

## **NOTES** 

**Analog Devices offers specific products designated for automotive applications; please consult your local Analog Devices sales representative for details. Standard products sold by Analog Devices are not designed, intended, or approved for use in life support, implantable medical devices, transportation, nuclear, safety, or other equipment where malfunction of the product can reasonably be expected to result in personal injury, death, severe property damage, or severe environmental harm. Buyer uses or sells standard products for use in the above critical applications at Buyer's own risk and Buyer agrees to defend, indemnify, and hold harmless Analog Devices from any and all damages, claims, suits, or expenses resulting from such unintended use.** 

> **©2009–2010 Analog Devices, Inc. All rights reserved. Trademarks and** 

**registered trademarks are the property of their respective owners. D07808-0-1/10(B)** 

Rev. B | Page 16 of 16