Low Noise, Low Drift, Low Power, 3-Axis MEMS Accelerometers Data Sheet ADXL356/ADXL357 FEATURES FUNCTIONAL BLOCK DIAGRAMS V V 1P8ANA 1P8DIG RANGE Hermetic package offers optimal long-term stability 0 g offset vs. temperature (all axes): 0.75 mg/C maximum LDO POWER V SUPPLY LDO Ultralow noise spectral density (all axes): 75 g/Hz MANAGEMENT X Y Low power, V (LDO regulator enabled) SUPPLY OUT X ANALOG ADXL356 in measurement mode: 150 A Z Y ST1 OUT FILTER 3-AXIS ADXL357 in measurement mode: 200 A Z ST2 SENSOR OUT CONTROL ADXL356/ADXL357 in standby mode: 21 A LOGIC STBY TEMP TEMP ADXL356 ADXL356 has user adjustable analog output bandwidth SENSOR V DDIO ADXL357 digital output features 2 V V Digital SPI and limited I C interfaces supported SSIO SS 20-bit ADC Figure 1. ADXL356 Data interpolation routine for synchronous sampling V V V 1P8ANA 1P8DIG DDIO Programmable high- and low-pass digital filters POWER MANAGEMENT Integrated temperature sensor LDO V LDO SUPPLY ADXL357 Voltage range options Y ADC INT1 X V with internal regulators: 2.25 V to 3.6 V CONTROL SUPPLY INT2 DIGITAL ANALOG ADC LOGIC Z FILTER FILTER DRDY V , V with internal LDO regulator bypassed: 1.8 V 1P8ANA 1P8DIG 3-AXIS ADC CS/SCL SENSOR typical 10% SCLK/V SSIO TEMP SERIAL FIFO ADC MOSI/SDA SENSOR I/O Operating temperature range: 40C to +125C MISO/ASEL 14-terminal, 6 mm 5.6 mm 2.2 mm, LCC package V V SSIO SS Figure 2. ADXL357 APPLICATIONS Inertial measurement units (IMUs)/attitude and heading reference systems (AHRSs) Platform stabilization systems Structural health monitoring Seismic imaging Tilt sensing Robotics Condition monitoring GENERAL DESCRIPTION The analog output ADXL356 and the digital output ADXL357 The low drift, low noise, and low power ADXL357 enables are low noise density, low 0 g offset drift, low power, 3-axis accurate tilt measurement in an environment with high accelerometers with selectable measurement ranges. The vibration. The low noise of the ADXL356 over higher ADXL356B supports the 10 g and 20 g ranges, the ADXL356C frequencies is ideal for condition-based monitoring and other supports the 10 g and 40 g ranges, and the ADXL357 supports vibration sensing applications. the 10 g, 20 g, and 40 g ranges. The ADXL357 multifunction pin names may be referenced only The ADXL356/ADXL357 offer industry leading noise, minimal by their relevant function for either the serial peripheral 2 C interface. offset drift over temperature, and long-term stability, enabling interface (SPI) or limited I precision applications with minimal calibration. 1 Protected by U.S. Patents 8,472,270 9,041,462 8,665,627 8,917,099 6,892,576 9,297,825 and 7,956,621. Rev. A 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 20172020 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. 15429-001 15429-002ADXL356/ADXL357 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 DRDY Pin .................................................................................... 29 Applications ....................................................................................... 1 FIFO FULL ................................................................................. 29 Functional Block Diagrams ............................................................. 1 FIFO OVR .................................................................................. 29 General Description ......................................................................... 1 Activity ......................................................................................... 29 Revision History ............................................................................... 3 External Synchronization and Interpolation .......................... 29 Specificat ions ..................................................................................... 4 ADXL357 Register Map ................................................................. 32 Analog Output for the ADXL356 ............................................... 4 Register Definitions........................................................................ 33 Digital Output for the ADXL357 ............................................... 5 Analog Devices ID Register ...................................................... 33 SPI Digital Interface Characteristics for the ADXL357 .......... 7 Analog Devices MEMS ID Register ......................................... 33 2 I C Digital Interface Characteristics for the ADXL357 ........... 8 Device ID Register ..................................................................... 33 Absolute Maximum Ratings ............................................................ 9 Product Revision ID Register ................................................... 33 Thermal Resistance ...................................................................... 9 Status Register ............................................................................. 33 Recommended Soldering Profile ............................................... 9 FIFO Entries Register ................................................................ 34 ESD Caution .................................................................................. 9 Temperature Data Registers ...................................................... 34 Pin Configurations and Function Descriptions ......................... 10 X-Axis Data Registers ................................................................ 34 Typical Performance Characteristics ........................................... 12 Y-Axis Data Registers ................................................................ 35 Root Allan Variance (RAV) ADXL357 Characteristics ......... 20 Z-Axis Data Registers ................................................................ 35 Theory of Operation ...................................................................... 21 FIFO Access Register ................................................................. 36 Applications Information .............................................................. 22 X-Axis Offset Trim Registers .................................................... 36 Analog Output ............................................................................ 22 Y-Axis Offset Trim Registers .................................................... 36 Digital Output ............................................................................. 22 Z-Axis Offset Trim Registers .................................................... 37 Axes of Acceleration Sensitivity ............................................... 23 Activity Enable Register ............................................................ 37 Power Sequencing ...................................................................... 23 Activity Threshold Registers ..................................................... 37 Power Supply Description ......................................................... 23 Activity Count Register ............................................................. 37 Overrange Protection ................................................................. 23 Filter Settings Register ............................................................... 38 Self Test ........................................................................................ 23 FIFO Samples Register .............................................................. 38 Filter ............................................................................................. 24 Interrupt Pin (INTx) Function Map Register......................... 38 Serial Communications ................................................................. 26 Data Synchronization ................................................................ 39 2 SPI Protocol ................................................................................. 26 I C Speed, Interrupt Polarity, and Range Register ................. 39 SPI Bus Sharing ........................................................................... 26 Power Control Register ............................................................. 39 2 I C Protocol ................................................................................. 27 Self Test Register ......................................................................... 40 Reading Acceleration or Temperature Data from the Interface Reset Register .............................................................................. 40 ....................................................................................................... 27 PCB Footprint Pattern ................................................................... 41 FIFO ................................................................................................. 28 Outline Dimensions ....................................................................... 42 Interrupts ......................................................................................... 29 Ordering Guide .......................................................................... 42 DATA RDY ................................................................................. 29 Rev. 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