ADXL330

Small, Low Power, 3-Axis ±3 g i MEMS® Accelerometer ADXL330 FEATURES 3-axis sensing Small, low-profile package 4 mm × 4 mm × 1.45 mm LFCSP Low power 180 μA at VS = 1.8 V (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 GENERAL DESCRIPTION The ADXL330 is a small, thin, low power, complete 3-axis accelerometer with signal conditioned voltage outputs, all on a single monolithic IC. 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 X and Y axes, and a range of 0.5 Hz to 550 Hz for the Z axis. The ADXL330 is available in a small, low profile, 4 mm × 4 mm × 1.45 mm, 16-lead, plastic lead frame chip scale package (LFCSP_LQ). APPLICATIONS Cost-sensitive, low power, motion- and tilt-sensing applications Mobile devices Gaming systems Disk drive protection Image stabilization Sports and health devices FUNCTIONAL BLOCK DIAGRAM +3V VS ADXL330 OUTPUT AMP 3-AXIS SENSOR CDC AC AMP DEMOD OUTPUT AMP RFILT XOUT CX RFILT YOUT CY RFILT OUTPUT AMP ZOUT CZ 05677-001 COM ST 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 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 ©2007 Analog Devices, Inc. All rights reserved. ADXL330 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 ...................................................................... 11 Mechanical Sensor...................................................................... 11 Performance................................................................................ 11 Applications..................................................................................... 12 Power Supply Decoupling ......................................................... 12 Setting the Bandwidth Using CX, CY, and CZ .......................... 12 Self Test ........................................................................................ 12 Design Trade-Offs for Selecting Filter Characteristics: The Noise/BW Trade-Off.................................................................. 12 Use with Operating Voltages Other than 3 V............................. 12 Axes of Acceleration Sensitivity ............................................... 13 Outline Dimensions ....................................................................... 14 Ordering Guide .......................................................................... 14 REVISION HISTORY 9/06—Rev. 0 to Rev. A Changes to Ordering Guide .......................................................... 14 3/06—Revision 0: Initial Version Rev. A | Page 2 of 16 ADXL330 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. Parameter SENSOR INPUT Measurement Range Nonlinearity Package Alignment Error Interaxis Alignment Error Cross Axis Sensitivity 1 SENSITIVITY (RATIOMETRIC) 2 Sensitivity at XOUT, YOUT, ZOUT Sensitivity Change Due to Temperature 3 ZERO g BIAS LEVEL (RATIOMETRIC) 0 g Voltage at XOUT, YOUT, ZOUT 0 g Offset vs. Temperature NOISE PERFORMANCE Noise Density XOUT, YOUT Noise Density ZOUT FREQUENCY RESPONSE 4 Bandwidth XOUT, YOUT 5 Bandwidth ZOUT5 RFILT Tolerance Sensor Resonant Frequency SELF TEST 6 Logic Input Low Logic Input High ST Actuation Current Output Change at XOUT Output Change at YOUT Output Change at ZOUT OUTPUT AMPLIFIER Output Swing Low Output Swing High POWER SUPPLY Operating Voltage Range Supply Current Turn-On Time 7 TEMPERATURE Operating Temperature Range T T Conditions Each axis % of full scale Min ±3 Typ ±3.6 ±0.3 ±1 ±0.1 ±1 300 ±0.015 1.5 ±1 280 350 Max Unit g % Degrees Degrees % Each axis VS = 3 V VS = 3 V Each axis VS = 3 V 270 330 mV/g %/°C V mg/°C μg/√Hz rms μg/√Hz rms Hz Hz kΩ kHz V V μA mV mV mV V V 1.2 1.8 No external filter No external filter 1600 550 32 ± 15% 5.5 +0.6 +2.4 +60 −150 +150 −60 0.1 2.8 1.8 3.6 320 1 −25 +70 Self test 0 to 1 Self test 0 to 1 Self test 0 to 1 No load No load VS = 3 V No external filter V μA ms °C 1 2 Defined as coupling between any two axes. 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 μF. Rev. A | Page 3 of 16 ADXL330 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Acceleration (Any Axis, Unpowered) Acceleration (Any Axis, Powered) VS All Other Pins Output Short-Circuit Duration (Any Pin to Common) Temperature Range (Powered) Temperature Range (Storage) Rating 10,000 g 10,000 g −0.3 V to +7.0 V (COM − 0.3 V) to (VS + 0.3 V) Indefinite −55°C to +125°C −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. TP RAMP-UP TEMPERATURE tP CRITICAL ZONE TL TO TP TL TSMAX TSMIN tL tS PREHEAT RAMP-DOWN 05677-002 t25°C TO PEAK TIME Figure 2. Recommended Soldering Profile Table 3. Recommended Soldering Profile Profile Feature Average Ramp Rate (TL to TP) Preheat Minimum Temperature (TSMIN) Maximum Temperature (TSMAX) Time (TSMIN to TSMAX), tS TSMAX to TL Ramp-Up Rate Time Maintained Above Liquidous (TL) Liquidous Temperature (TL) Time (tL) Peak Temperature (TP) Time within 5°C of Actual Peak Temperature (tP) Ramp-Down Rate Time 25°C to Peak Temperature Sn63/Pb37 3°C/s max 100°C 150°C 60 s to 120 s 3°C/s max 183°C 60 s to 150 s 240°C + 0°C/−5°C 10 s to 30 s 6°C/s max 6 minutes max Pb-Free 3°C/s max 150°C 200°C 60 s to 180 s 3°C/s max 217°C 60 s to 150 s 260°C + 0°C/−5°C 20 s to 40 s 6°C/s max 8 minutes max ESD CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. Rev. A | Page 4 of 16 ADXL330 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS 0.50 MAX 0.65 16 15 14 13 12 11 10 9 7 8 NC NC VS VS 4 0.325 NC ST COM NC 1 2 3 4 5 ADXL330 TOP VIEW (Not to Scale) +Y +Z +X 6 XOUT NC YOUT NC 0.35 MAX 0.65 4 1.95 0.325 05677-029 COM COM COM ZOUT NC = NO CONNECT CENTER PAD IS NOT INTERNALLY CONNECTED BUT SHOULD BE SOLDERED FOR MECHANICAL INTEGRITY 1.95 DIMENSIONS SHOWN IN MILLIMETERS 05677-032 Figure 3. Pin Configuration Figure 4. Recommended PCB Layout Table 4. Pin Function Descriptions Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Mnemonic NC ST COM NC COM COM COM ZOUT NC YOUT NC XOUT NC VS VS NC Description No Connect Self Test Common No Connect Common Common Common Z Channel Output No Connect Y Channel Output No Connect X Channel Output No Connect Supply Voltage (1.8 V to 3.6 V) Supply Voltage (1.8 V to 3.6 V) No Connect Rev. A | Page 5 of 16 ADXL330 TYPICAL PERFORMANCE CHARACTERISTICS N > 1000 for all typical performance plots, unless otherwise noted. 35 30 25 20 15 16 14 12 % OF POPULATION % OF POPULATION 05677-003 10 8 6 4 05677-006 10 5 2 0 0.95 0.96 0.97 0.98 0.99 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 0 1.42 1.44 1.46 1.48 1.50 1.52 1.54 1.56 1.58 OUTPUT (V) OUTPUT (V) Figure 5. X-Axis Zero g Bias at 25°C, VS = 3 V 40 35 30 16 14 12 Figure 8. X-Axis Zero g Bias at 25°C, VS = 2 V % OF POPULATION 25 20 15 10 05677-004 % OF POPULATION 10 8 6 4 05677-007 5 0 1.42 1.44 1.46 1.48 1.50 1.52 1.54 1.56 1.58 OUTPUT (V) 2 0 0.95 0.96 0.97 0.98 0.99 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 OUTPUT (V) Figure 6. Y-Axis Zero g Bias at 25°C, VS = 3 V Figure 9. Y-Axis Zero g Bias at 25°C, VS = 2 V 25 40 35 20 30 % OF POPULATION 25 20 15 10 % OF POPULATION 05677-005 15 10 5 05677-008 5 0 1.42 1.44 1.46 1.48 1.50 1.52 1.54 1.56 1.58 OUTPUT (V) 0 0.88 0.90 0.92 0.94 0.96 0.98 1.00 1.02 1.04 1.06 1.08 1.10 1.12 1.14 1.16 OUTPUT (V) Figure 7. Z-Axis Zero g Bias at 25°C, VS = 3 V Figure 10. Z-Axis Zero g Bias at 25°C, VS = 2 V Rev. A | Page 6 of 16 ADXL330 35 30 1.53 25 20 15 1.55 N=8 1.54 % OF POPULATION 1.52 1.51 VOLTS 05677-009 1.50 1.49 1.48 1.47 1.46 1.45 –30 05677-012 10 5 0 –2.5 –2.0 –1.5 –1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5 TEMPERATURE COEFFICIENT (mg/°C) –20 –10 0 10 20 30 40 50 60 70 80 TEMPERATURE (°C) Figure 11. X-Axis Zero g Bias Temperature Coefficient, VS = 3 V Figure 14. X-Axis Zero g Bias vs. Temperature—8 Parts Soldered to PCB 40 35 30 1.55 N=8 1.54 1.53 % OF POPULATION 1.52 25 1.51 VOLTS 05677-010 20 15 10 1.50 1.49 1.48 1.47 1.46 1.45 –30 05677-013 5 0 –2.5 –2.0 –1.5 –1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5 TEMPERATURE COEFFICIENT (mg/°C) –20 –10 0 10 20 30 40 50 60 70 80 TEMPERATURE (°C) Figure 12. Y-Axis Zero g Bias Temperature Coefficient, VS = 3 V 30 Figure 15. Y-Axis Zero g Bias vs. Temperature—8 Parts Soldered to PCB 1.55 N=8 1.54 25 1.53 1.52 1.51 % OF POPULATION 20 VOLTS 05677-011 15 1.50 1.49 10 1.48 1.47 1.46 1.45 –30 05677-014 5 0 –2.5 –2.0 –1.5 –1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5 TEMPERATURE COEFFICIENT (mg/°C) –20 –10 0 10 20 30 40 50 60 70 80 TEMPERATURE (°C) Figure 13. Z-Axis Zero g Bias Temperature Coefficient, VS = 3 V Figure 16. Z-Axis Zero g Bias vs. Temperature—8 Parts Soldered to PCB Rev. A | Page 7 of 16 ADXL330 60 35 30 25 20 50 % OF POPULATION 40 30 % OF POPULATION 05677-015 15 20 10 5 10 0 0.26 0.27 0.28 0.29 0.30 0.31 0.32 0.33 0.34 SENSITIVITY (V/g) 0 0.170 0.174 0.178 0.182 0.186 0.190 0.194 0.198 0.202 0.206 0.210 SENSITIVITY (V/g) Figure 17. X-Axis Sensitivity at 25°C, VS = 3 V 70 40 35 30 Figure 20. X-Axis Sensitivity at 25°C, VS = 2 V 60 50 40 % OF POPULATION % OF POPULATION 25 20 15 10 30 20 05677-016 0 0.26 0.27 0.28 0.29 0.30 0.31 0.32 0.33 0.34 SENSITIVITY (V/g) 0 0.170 0.174 0.178 0.182 0.186 0.190 0.194 0.198 0.202 0.206 0.210 SENSITIVITY (V/g) Figure 18. Y-Axis Sensitivity at 25°C, VS = 3 V 70 40 35 30 Figure 21. Y-Axis Sensitivity at 25°C, VS = 2 V 60 50 40 % OF POPULATION % OF POPULATION 25 20 15 10 30 20 10 0 0.25 0.26 0.27 0.28 0.29 0.30 0.31 0.32 0.33 SENSITIVITY (V/g) 05677-017 0 0.172 0.176 0.180 0.184 0.188 0.192 0.196 0.200 0.204 0.208 0.212 SENSITIVITY (V/g) Figure 19. Z-Axis Sensitivity at 25°C, VS = 3 V Figure 22. Z-Axis Sensitivity at 25°C, VS = 2 V Rev. A | Page 8 of 16 05677-020 5 05677-019 10 5 05677-018 ADXL330 90 80 0.32 70 0.33 N=8 % OF POPULATION 50 40 30 20 SENSITIVITY (V/g) 05677-021 60 0.31 0.30 0.29 0.28 10 0 –2.0 –1.6 –1.2 –0.8 –0.4 0 0.4 0.8 1.2 1.6 2.0 DRIFT (%) 05677-024 0.27 –30 –20 –10 0 10 20 30 40 50 60 70 80 TEMPERATURE (°C) Figure 23. X-Axis Sensitivity Drift Over Temperature, VS = 3 V Figure 26. X-Axis Sensitivity vs. Temperature 8 Parts Soldered to PCB, VS = 3 V 0.33 N=8 70 60 50 40 30 20 0.32 % OF POPULATION SENSITIVITY (V/g) 05677-022 0.31 0.30 0.29 0 –2.0 –1.6 –1.2 –0.8 –0.4 0 0.4 0.8 1.2 1.6 2.0 DRIFT (%) 0.27 –30 –20 –10 0 10 20 30 40 50 60 70 80 TEMPERATURE (°C) Figure 24. Y-Axis Sensitivity Drift Over Temperature, VS = 3 V 25 0.33 Figure 27. Y-Axis Sensitivity vs. Temperature 8 Parts Soldered to PCB, VS = 3 V N=8 20 0.32 % OF POPULATION 15 SENSITIVITY (V/g) 0.31 0.30 10 0.29 5 05677-023 0.28 05677-026 0 –1.0 –0.6 –0.2 0.2 0.6 1.0 1.4 1.8 2.2 2.6 3.0 DRIFT (%) 0.27 –30 –20 –10 0 10 20 30 40 50 60 70 80 TEMPERATURE (°C) Figure 25. Z-Axis Sensitivity Drift Over Temperature, VS = 3 V Figure 28. Z-Axis Sensitivity vs. Temperature 8 Parts Soldered to PCB, VS = 3 V Rev. A | Page 9 of 16 05677-025 10 0.28 ADXL330 600 T 500 400 CURRENT (µA) 4 300 3 200 2 1 05677-028 100 05677-027 0 0 1 2 3 SUPPLY (V) 4 5 6 CH1 1.00V BW CH2 500mV CH3 500mV CH4 500mV B W M1.00ms T 9.400% A CH1 300mV Figure 29. Typical Current Consumption vs. Supply Voltage Figure 30. Typical Turn-On Time—CX, CY, CZ = 0.0047 μF, VS = 3 V Rev. A | Page 10 of 16 ADXL330 THEORY OF OPERATION The ADXL330 is a complete 3-axis acceleration measurement system on a single monolithic IC. The ADXL330 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 ADXL330 uses a single structure for sensing the X, Y, and Z axes. As a result, the three axes sense directions are highly orthogonal with 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 high performance is built-in to the ADXL330. As a result, there is neither quantization error nor nonmonotonic behavior, and temperature hysteresis is very low (typically less than 3 mg over the −25°C to +70°C temperature range). Figure 14, Figure 15, and Figure 16 show the zero g output performance of eight parts (X-, Y-, and Z-axis) soldered to a PCB over a −25°C to +70°C temperature range. Figure 26, Figure 27, and Figure 28 demonstrate the typical sensitivity shift over temperature for supply voltages of 3 V. This is typically better than ±1% over the −25°C to +70°C temperature range. Rev. A | Page 11 of 16 ADXL330 APPLICATIONS POWER SUPPLY DECOUPLING For most applications, a single 0.1 μF capacitor, CDC, placed close to the ADXL330 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 as 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 ADXL330 ground to the power supply ground is low impedance because noise transmitted through ground has a similar effect as noise transmitted through VS. 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 ADXL330 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 ADXL330 noise has the characteristics of white Gaussian noise, which contributes equally at all frequencies and is described in terms of μg/√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 ADXL330 is determined by rms Noise = Noise Density × ( BW × 1.6 ) SETTING THE BANDWIDTH USING CX, CY, AND CZ The ADXL330 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 F−3 dB = 1/(2π(32 kΩ) × C(X, Y, Z)) or more simply F–3 dB = 5 μF/C(X, Y, Z) 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 5. Filter Capacitor Selection, CX, CY, and CZ Bandwidth (Hz) 1 10 50 100 200 500 Capacitor (μF) 4.7 0.47 0.10 0.05 0.027 0.01 Often, the peak value of the noise is desired. Peak-to-peak noise can only be estimated by statistical methods. Table 6 is useful for estimating the probabilities of exceeding various peak values, given the rms value. Table 6. Estimation of Peak-to-Peak Noise Peak-to-Peak Value 2 × rms 4 × rms 6 × rms 8 × rms % of Time that Noise Exceeds Nominal Peak-to-Peak Value 32 4.6 0.27 0.006 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 −500 mg (corresponding to −150 mV) in the X-axis, 500 mg (or 150 mV) on the Y-axis, and −200 mg (or −60 mV) on the Z-axis. This ST pin may be left open circuit or connected to common (COM) in normal use. USE WITH OPERATING VOLTAGES OTHER THAN 3 V The ADXL330 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. Rev. A | Page 12 of 16 ADXL330 The ADXL330 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, so 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- and Y-axis noise density is typically 230 μg/√Hz, while at VS = 2 V, the X- and Y-axis noise density is typically 350 μg/√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 ADXL330 is approximately −275 mV for the X-axis, +275 mV for the Y-axis, and −100 mV for the Z-axis. XOUT = –1g YOUT = 0g ZOUT = 0g TOP At VS = 2 V, the self test response is approximately −60 mV for the X-axis, +60 mV for the Y-axis, and −25 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 AZ AY AX Figure 31. Axes of Acceleration Sensitivity, Corresponding Output Voltage Increases When Accelerated Along the Sensitive Axis TOP GRAVITY XOUT = 0g YOUT = 1g ZOUT = 0g XOUT = 0g YOUT = –1g ZOUT = 0g TOP TOP TOP XOUT = 1g YOUT = 0g ZOUT = 0g TOP Figure 32. Output Response vs. Orientation to Gravity Rev. A | Page 13 of 16 05677-031 XOUT = 0g YOUT = 0g ZOUT = 1g XOUT = 0g YOUT = 0g ZOUT = –1g 05677-030 ADXL330 OUTLINE DIMENSIONS 0.20 MIN 0.20 MIN 13 16 1 PIN 1 INDICATOR 2.43 1.75 SQ 1.08 PIN 1 INDICATOR TOP VIEW 4.15 4.00 SQ 3.85 0.65 BSC 12 BOTTOM VIEW 9 8 5 4 0.55 0.50 0.45 1.50 1.45 1.40 SEATING PLANE 0.05 MAX 0.02 NOM 0.35 0.30 0.25 COPLANARITY 0.05 1.95 BSC *STACKED DIE WITH GLASS SEAL. Figure 33. 16-Lead Lead Frame Chip Scale Package [LFCSP_LQ] 4 mm × 4 mm Body, Thick Quad (CP-16-5a*) Dimensions shown in millimeters ORDERING GUIDE Model ADXL330KCPZ 1 ADXL330KCPZ–RL1 EVAL-ADXL330Z1 1 Measurement Range ±3 g ±3 g Specified Voltage 3V 3V Temperature Range −25°C to +70°C −25°C to +70°C Package Description 16-Lead LFCSP_LQ 16-Lead LFCSP_LQ Evaluation Board 072606-A Package Option CP-16-5a CP-16-5a Z = Pb-free part. Rev. A | Page 14 of 16 ADXL330 NOTES Rev. A | Page 15 of 16 ADXL330 NOTES ©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05677-0-6/07(A) Rev. A | Page 16 of 16