ADXL345-EP

ADXL345-EP (Rev. B)

Document overview

• Manufacturer or author: Analog Devices, Inc.
• PDF pages: 12

Technical content

3-Axis, ±2 g/±4 g/±8 g/±16 g Digital Accelerometer Enhanced Product ADXL345-EP Rev. B Document Feedback 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. Tel: 781.329.4700 © 2009–2013 Analog Devices, Inc. All rights reserved. Technical Support www.analog.com

FEATURES

Ultralow power: as low as 23 µA in measurement mode and 0.1 µA in standby mode at VS = 2.5 V (typical) Power consumption scales automatically with bandwidth User-selectable resolution from 10 to 13 bits 4 mg/LSB scale factor in all g ranges 32-sample FIFO minimizes host processor load Single tap, double tap, and free-fall detection Activity/inactivity monitoring Supply voltage range: 2.0 V to 3.6 V I/O voltage range: 1.7 V to VS SPI (3- and 4-wire) and I2C digital interfaces Flexible interrupt modes mappable to either interrupt pin Measurement ranges selectable via serial command Bandwidth selectable via serial command 10,000 g shock survival Pb free/RoHS compliant Small and thin: 3 mm × 5 mm × 1 mm LGA package ENHANCED PRODUCT FEATURES Supports defense and aerospace applications (AQEC standard) Extended industrial temperature range (−55°C to +105°C) Controlled manufacturing baseline One assembly/test site One fabrication site Enhanced product change notification Qualification data available on request

APPLICATIONS

The ADXL345-EP is an extended performance version of the ADXL345, which is a small, thin, ultralow power, 3-axis accelerometer with high resolution (13-bit) measurement at up to ±16 g. Digital output data is formatted as 16-bit twos complement and is accessible through either a SPI (3- or 4-wire) or I2C digital interface. The ADXL345-EP is well suited for extended temperature range industrial and aerospace equipment. It measures the static acceleration of gravity in tilt-sensing applications, as well as dynamic acceleration resulting from motion or shock. Its high resolution (3.9 mg/LSB) enables measurement of inclination changes less than 1.0°. Several special sensing functions are provided. Activity and inactivity sensing detect the presence or lack of motion by comparing the acceleration on any axis with user-set thresholds. Tap sensing detects single and double taps in any direction. Free- fall sensing detects if the device is falling. These functions can be mapped individually to either of two interrupt output pins. An integrated memory management system with a 32-level first in, first out (FIFO) buffer can be used to store data to minimize host processor activity and lower overall system power consumption. Low power modes enable intelligent motion-based power management with threshold sensing and active acceleration measurement at extremely low power dissipation. The ADXL345-EP is supplied in a small, thin, 3 mm × 5 mm × 1 mm, 14-lead, enhanced plastic package. FUNCTIONAL BLOCK DIAGRAM 3-AXIS SENSOR SENSE ELECTRONICS DIGITAL FILTER ADXL345-EP POWER MANAGEMENT CONTROL AND INTERRUPT LOGIC SERIAL I/O INT1 VS VDD I/O INT2 SDA/SDI/SDIO SDO/ALT ADDRESS SCL/SCLK GND ADC

32 LEVEL

Figure 1.

ADXL345-EP Enhanced Product Rev. B | Page 2 of 12 TABLE OF CONTENTS

REVISION HISTORY

4/13—Rev. A to Rev. B Deleted Package Information Section, Figure 2, and Table 4, 2/13—Rev. 0 to Rev. A 12/11—Revision 0: Initial Version RELATED DOCUMENTS The ADXL345-EP is, by definition, an extended performance variation of the ADXL345 accelerometer. All ADXL345 datasheet descriptions are applicable and not repeated in this document, so users should refer to it for complete functionality and product description. Information and data in this ADXL345-EP subset datasheet supersede those in the standard ADXL345 datasheet.

Enhanced Product ADXL345-EP Rev. B | Page 3 of 12 SPECIFICATIONS TA = 25°C, VS = 2.5 V, VDD I/O = 1.8 V , acceleration = 0 g, CS = 10 µF tantalum, CI/O = 0.1 µF, output data rate (ODR) = 800 Hz, unless otherwise noted. All minimum and maximum specifications are guaranteed. Typical specifications are not guaranteed. Table 1. Parameter Test Conditions Min Typ1 Max Unit SENSOR INPUT Each axis Measurement Range User selectable ±2, ±4, ±8, ±16 g Nonlinearity Percentage of full scale ±0.5 % Inter-Axis Alignment Error ±0.1 Degrees Cross-Axis Sensitivity2 ±1 % OUTPUT RESOLUTION Each axis All g Ranges 10-bit resolution 10 Bits ±2 g Range Full resolution 10 Bits ±4 g Range Full resolution 11 Bits ±8 g Range Full resolution 12 Bits ±16 g Range Full resolution 13 Bits SENSITIVITY Each axis Sensitivity at XOUT, YOUT, ZOUT All g-ranges, full resolution 230 256 282 LSB/g ±2 g, 10-bit resolution 230 256 282 LSB/g ±4 g, 10-bit resolution 115 128 141 LSB/g ±8 g, 10-bit resolution 57 64 71 LSB/g ±16 g, 10-bit resolution 29 32 35 LSB/g Sensitivity Deviation from Ideal All g-ranges ±1.0 % Scale Factor at XOUT, YOUT, ZOUT All g-ranges, full resolution 3.5 3.9 4.3 mg/LSB ±2 g, 10-bit resolution 3.5 3.9 4.3 mg/LSB ±4 g, 10-bit resolution 7.1 7.8 8.7 mg/LSB ±8 g, 10-bit resolution 14.1 15.6 17.5 mg/LSB ±16 g, 10-bit resolution 28.6 31.2 34.5 mg/LSB Sensitivity Change Due to Temperature ±0.01 %/°C 0 g OFFSET Each axis 0 g Output for XOUT, YOUT −150 0 +150 mg 0 g Output for ZOUT −250 0 +250 mg 0 g Output Deviation from Ideal, XOUT, YOUT ±35 mg 0 g Output Deviation from Ideal, ZOUT ±40 mg 0 g Offset vs. Temperature for X-, Y-Axes ±0.4 mg/°C 0 g Offset vs. Temperature for Z-Axis ±1.2 mg/°C NOISE X-, Y-Axes ODR = 100 Hz for ±2 g, 10-bit resolution or all g-ranges, full resolution

0.75 LSB rms

Z-Axis ODR = 100 Hz for ±2 g, 10-bit resolution or all g-ranges, full resolution

1.1 LSB rms

OUTPUT DATA RATE AND BANDWIDTH User selectable Output Data Rate (ODR)3, 4, 5 0.1 3200 Hz SELF-TEST6 Output Change in X-Axis 0.20 2.10 g Output Change in Y-Axis −2.10 −0.20 g Output Change in Z-Axis 0.30 3.40 g POWER SUPPLY Operating Voltage Range (VS) 2.0 2.5 3.6 V Interface Voltage Range (VDD I/O) 1.7 1.8 VS V Supply Current ODR ≥ 100 Hz 140 µA ODR < 10 Hz 23 µA Standby Mode Leakage Current 0.1 µA Turn-On and Wake-Up Time7 ODR = 3200 Hz 1.4 ms

ADXL345-EP Enhanced Product Rev. B | Page 4 of 12 Parameter Test Conditions Min Typ1 Max Unit TEMPERATURE Operating Temperature Range −55 +105 °C WEIGHT Device Weight 30 mg 1 The typical specifications shown are for at least 68% of the population of parts and are based on the worst case of mean ±1 σ, except for 0 g output and sensitivity, which represents the target value. For 0 g output and sensitivity, the deviation from the ideal describes the worst case of mean ±1 σ. 2 Cross-axis sensitivity is defined as coupling between any two axes. 3 Bandwidth is the −3 dB frequency and is defined as half the output data rate, bandwidth = ODR/2. 4 The output format for the 3200 Hz and 1600 Hz ODRs is different from the output format for the remaining ODRs. This difference is described in the ADXL345 data sheet. 5 Output data rates below 6.25 Hz exhibit additional offset shift with increased temperature, depending on selected output data rate. Refer to the ADXL345 data sheet for details. 6 Self-test change is defined as the output (g) when the SELF_TEST bit = 1 (in the DATA_FORMAT register, Address 0x31) minus the output (g) when the SELF_TEST bit = 0. Due to device filtering, the output reaches its final value after 4 × τ when enabling or disabling self-test, where τ = 1/(data rate). The part must be in normal power operation (LOW_POWER bit = 0 in the BW_RATE register, Address 0x2C) for self-test to operate correctly. 7 Turn-on and wake-up times are determined by the user-defined bandwidth. At a 100 Hz data rate, the turn-on and wake-up times are each approximately 11.1 ms. For other data rates, the turn-on and wake-up times are each approximately τ + 1.1 in milliseconds, where τ = 1/(data rate).

Table 3. Package Characteristics

Figure 2. Pin Configuration (Top View) Table 4. Pin Function Descriptions 1 V DD I/O Digital Interface Supply Voltage. 2 GND This pin must be connected to ground. 3 RESERVED Reserved. This pin must be connected to VS or left open. 4 GND This pin must be connected to ground. 5 GND This pin must be connected to ground. 10 NC Not Internally Connected. 11 RESERVED Reserved. This pin must be connected to ground or left open. 12 SDO/ALT ADDRESS Serial Data Output (SPI 4-Wire)/Alternate I2C Address Select (I2C). 13 SDA/SDI/SDIO Serial Data (I 2C)/Serial Data Input (SPI 4-Wire)/Serial Data Input and Output (SPI 3-Wire). 14 SCL/SCLK Serial Communications Clock. SCL is the clock for I2C, and SCLK is the clock for SPI.

Figure 12. 14-Terminal Land Grid Array [LGA]

ADXL345-EP Enhanced Product Rev. B | Page 10 of 12 NOTES

Enhanced Product ADXL345-EP Rev. B | Page 11 of 12 NOTES

ADXL345-EP Enhanced Product Rev. B | Page 12 of 12 NOTES Analog Devices offers sp ecific products designated for automotive applications; please consult your local Analog Devices sales representative for det ails. 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 u se 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. ©2009–2013 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D10413-0-4/13(B)