Freescale Sensors Overview Freescale Sensor Portfolio. Sensor Fusion Enablement Tools Back Up: Deep Dive

Transcription

1 August 2013

2 Freescale Sensors Overview Freescale Sensor Portfolio Linear Inertial Sensors - Accelerometers Linear Inertial Sensors - Intelligent Sensor Hub Rotational Inertial & Magnetic Sensors - Gyro & Magnetometers Pressure Sensors Sensor Fusion Enablement Tools Back Up: Deep Dive 2

3 ecompass Magnetometers Accelerometers Touch Sensors Gyro Altimeter / Pressure 3

4 4

5 Freescale Xtrinsic sensing solutions offer increased levels of modular integration combined with multiple sensor inputs, logic and other building blocks to bring greater value and decision making to the overall sensing solution. Xtrinsic Sensing Solutions Increasing levels of intelligence Decision making Software enablement Programmability Applications Third-party software Increasing levels of integration Sensor fusion Non-volatile storage Connectivity Power management Logic Actuation 5

6 - Today + Mobile Devices Mobile Phones Tablets Laptops / Hybrids MID Consumer Non-Mobile Digital Still Camera Remote Controls Gaming Pedometers GPS Watches - Activity / fitness monitors - Mobile phones with cameras are now embracing dedicated gyroscopes for image stabilization -Samsung leading the way to mobile phone adoption of pressure sensor in S III and Note II for indoor navigation assist. - Sports training equip - Hobbyist - RCs Seemingly Endless Opportunity 6

7 - Today + Instrumentation Blood Pressure cuff Blood Pressure invasive Respiratory inhalers, ventilators Therapy CPAP Sleep Apnea Pulmonary Embolism Hospital Beds Nebulizers Diagnostics Activity / Gate Analysis Heart rate Sleep quality - Activity/Fitness Monitors - Wound management -Wearable devices using sensors to monitor the movements of patients undergoing physical rehabilitation -Sensors providing higher accuracy feedback loops for improved performance of -prosthetic devices. Again. Seemingly Endless Opportunity 7

8 - Today + Appliances Washing machines Dishwasher Coffee Maker / Beverage Dispenser Rice Cookers General Industrial Fluid Level Pressure Switch Heating, Ventilation and Air Conditioning Pump controls Industrial controls - Navigation -Vibration monitoring moving from advanced predictive maintenance to eventually active compensation - Security -Asset Tracking 8

9 -Today + Radar (77 GHz) Inertial & Pressure Side Crash Satellite Vehicle Stability (Inertial) -Mandates on tire pressure monitoring and vehical dynamics continue to drive sensor growth beyond semiconductor market -Navigation - GPS Assist Engine Control (Pressure) Suspension Control (Inertial) -High Pressure applications expanding -Magnetics for Motor Control Airbag ECU (Inertial) Tire Pressure Monitoring System Electric Parking Brake (Inertial) 9

10

11 11

12 MMA8451/52/53 3-axis ±2, ±4, ±8 g 10/12/14-bit Digital I 2 C Embedded function and interrupt : (FIFO, High pass filter, P/L, ) Ultra low noise (99 µg/ Hz), low TCO (0.15mg/ C) High performance Consumer & Industrial Down to 0.25mg/LSB sensitivity Volt, 3 x 3 x 1 mm QFN Sample Prod SRP$ Applications Web ok FXLS axis ±2, ±4, ±8 g 14-bit Digital SPI Now Nov-13 TBD Embedded functions and interrupts ( all + Vector magnitude) High performance industrial grade Volt, 3 x 3 x 1 mm QFN MMA8652/53 3-axis ±2, ±4, ±8 g 10/12-bit Digital I 2 C Web Now 0.53 Embedded functions and interrupts (8652 same than MMA8451) Software compatible with the MMA845x family Low cost Volt, 2 x 2 mm DFN Tilt Measurement Pedometer Power Management ecompass Asset Tracking Activity Monitor DECT Phones Sports Watch Fleet Management Remote Controls Appliance MMA axis Tilt Sensor 14-bit Digital I 2 C + 3 Logic Out Now Now 0.77 Ball-in-a-Box Ultra low power down to 400 na/hz, 3 logic outputs to flag tilt on the 3 axis I²C interface to read raw acceleration data Volt, 3 x 3 x 1 mm DFN Drivers Available on request Tamper Sensor Alarm/Security Freefall Detect Remote Control Low Power Wake-up 12

13 Sample Prod SRP$ Applications FXLN axis ±2/±8 g Analog Out, low bandwidth Now Nov Vibration Monitoring FXLN axis ±8/±16 g Analog Out, low bandwidth Now Nov FXLN axis ±2/±8 g Analog Out, high bandwidth Now Nov FXLN axis ±8/±16 g Analog Out, high bandwidth Now Nov High Bandwidth: up to 4.9 khz on XY and 2.1 khz on Z axis Low Bandwidth : up to 1.7 khz on XYZ axis Low power 200 µa in running mode, low voltage High performance industrial grade Volt, 3 x 3 x 1mm, 0.65mm pitch 12 pins QFN -High Precision -Industrial Control -Sport Applications -Preventive Maintenance MMA6900Q 2-axis XY, ±3.5g, 11 bits, SPI, AECQ100 Now Now 4.77 MMA6901Q 2-axis XY, ±5g, 11 bits, SPI, AECQ100 AECQ100 qualified, -40 C;+105 C Low pass filters for noisy environment Low TCO over the wide temperature window. QFN 6x6mm, 16 pins QFN -Vehicle stability control -Electronic parking brake -Car alarm - Trailer tilt control -Absolute tilt measurement - Noisy environment Drivers Available on request 13

14 Driver Mag The upcoming challenges from the increasing number of sensors: Applications Processor Driver Driver Pressure Each sensor requests its own set of interface (I2C, SPI, level shifter ), driver and software (offset compensation, specific setting ) Increasing data flow to be processed by the Apps processor Power budget management and optimization Higher software complexity to manage and adapt to each sensor Applications Processor Accel Sensor hub architecture MEMS accelerometer Processing Software Sensor Hub Touch Magnetic Pressure 14

15 Host Power Management ColdFire V1 32-Bit Processor Firmware Version: xx All Sensor Device IDs ROM version Hardware version Date code for build Build number Connectivity: I 2 C/SPI An Intelligent Sensor Hub manages: How to talk to each sensor How to configure each sensor How often to talk to each sensor When to listen to each sensor What data is pertinent to the application and much more. Accelerometer Gyro (FXAS21000) Pressure (MPL3115) Touch (MPR121) Magnetic (MAG3110) Resolution: 10-, 12-, 14-, and 16-bit Turn on Time: Sample Rate Device ID: 0xXX Interrupts to set: Resolution: 16 bits Turn on Time: xx Sample Rate: xx Interrupts to set: xx Device ID: 0xXX Resolution: 16 bits Turn on Time: xx Sample Rate: xx Interrupts to set: xx Device ID: 0xXX Resolution: 16 bits Turn on Time: xx Sample Rate: xx Interrupts to set: xx Device ID: 0xXX Resolution: 16 bits Turn on Time: xx Sample Rate: xx Interrupts to set: xx 15

16 Demo MMA955xL 32-Bit 16K Flash CPU and 3-axis Accelerometer FXLC95000CL 32-Bit 128K Flash CPU and 3-axis Accelerometer Embedded ±2, ±4, ±8 g 3-axis 16-Bit accelerometer module 32-Bit CF V1 CPU with MAC multiply and accumulate block 16K or 128K on-chip Flash, 2K or 16K on-chip SRAM SPI, I²C (master and slave), GPIO, ADC, PWM 1.8V, 3 x 3 x 1 mm QFN, or 3 x 5 x 1 mm QFN Pre-flashed Freescale firmware (3 Versions) or MQX CodeWarrior CW10.x supported Part Number Firmware User Memory Size MMA9559L Basic 14K Flash 1.5K SRAM Now Now MMA9550L Infrastructure 6.5K Flash 0.5K SRAM Now Now MMA9551L Infrastructure and Gesture 4.5K Flash 0.5K SRAM Now Now MMA9553L High end pedometer 1.5K Flash 0.2K SRAM Now Now Sample Prod SRP$ Applications Tilt Measurement Vibration Monitor Pedometer Home Health Power Management ecompass Asset Tracking Collision Recorder starting at 1.79 FXLC95000 MQX enabled 128K Flash 16K SRAM Now Sep-13 3-Axis MEMS Accelerometer ROM Flash RAM ADC GPIO ColdFire 32-Bit V1 Core SPI I2C 16

17 3-axis accelerometer plus Coldfire MCU that enables scalable, autonomous, high precision multisensor hub solutions with local compute and sensors management in an open architecture Differentiating Points System in Package: 32-bit MCU and 3-axis accelerometer Open MCU architecture enables differentiated creativity First open programming model with library support Compute and actuate locally Best in class accelerometer noise & resolution performance When to choose FXLC95000CL Sensor hub managing multiple sensors: FSL & others Pass through data as needed i.e. heading Perform 6-axis fusion Mag/accel cal/ecompass Gyro/accel When to choose Kinetis Sensor fusion for 3+ sensors > M0+ Sensor fusion and much more > M4 Specification FXLC95000CL KL25 K2 Core Coldfire V1 w/embedded accelerometer ARM Cortex M0+ Sensor Hub 17 ARM Cortex M4 9-Axis Fusion Multiple sensors + other computations Sensor Fusion 6-axis Ecompass Cal 9-Axis Fusion 3 sensors+ Euler Angles Quarterions Rotation Matrices ISF Supported

18 Sample Prod SRP$ Applications MAG3110G 3-axis Digital Magnetometer Web Now 0.56 Industrial Compass Capable of measuring geomagnetic fields Current Sensing Wide dynamic range +/ μt (10 Gauss) Presence Detection Low power in measurement mode 8.6 μa. Car Detect ODR Output data rate up to 80 Hz Industrial Safety Interrupt pin trigger when new data available Magnetic Tamper Tilt compensation and Soft/Hard Iron calibration SW available Sports Watch Volt, 2 x 2 x 0.85 mm DFN Diving Watch FXOS8700CQ COMBO 6-axis Magnetometer and Accelerometer Capable of measuring geomagnetic fields with + = Tilt compensation Wider dynamic range +/ μt ODR up to 800 Hz by sensors, or 400Hz in Hybrid mode Embedded interrupts and pre-programmed functions Low power 80 μa in Hybrid 25 Hz Volt, 3 x 3 x 1.2 mm QFN 2 x 2 mm 3 x 3 mm 3 x 3 mm Now Now 1.25 FXAS axis Digital Gyroscope Jul-13 Oct Inertial Navigation Full scale range +/-1600 /sec Gaming Angular speed resolution better than 0.2 /sec Remote Control Current consumption in run mode : 5.5mA Smart Phones 1.95V-3.6V voltage supply, 4 x 4 x 1 mm QFN 18

19 Differentiating Points Angular acceleration resolution better than 0.2 /s Programmable interrupts Power saving features Product Features V supply voltage Output data rates (ODR) from 1Hz to 200Hz Full scale range: ±1600 /s Bias stability over temperature: ±0.3 /s Random walk(over 1minute): ±0.007 /s Typical Applications Controllers: Remotes, Games Mobile: Phones, Tablets, ereaders Sports Monitoring Real-time orientation detection Static orientation detection Package 4x4x1mm QFN, 0.5mm pitch Availability Samples: NOW (On Request) Production: October

20 Differential P1 P2 Differential Measures differences between two pressure points (P1 and P2) Gauge P1 P2 = A Special type of differential measurement. One side exposed to Atmosphere (P2 = Atmosphere Pressure) Absolute P1 Reference Constraint Waver Only one side is accessible. Internal (P2) is referenced to vacuum or sealed air inside. For All: P1>P2 for positive voltage output 20

21 Sample Prod SRP$ Applications MPXHZ9 Series kpa Digital Absolute Pressure Sensor Fuel Injection 1.5% max error over 0 to 85 C Comfort Seating 5 V power supply LPG Gas Market Media resistant gel AECQ100 qualified Drop in replacment of the MPXHZ6xxx series MPXHZ9115A6T kpa No port Now Q1-14 MPXHZ9115AC6T kpa Port Now Q2-14 MPXHZ9250A6T kpa No port Now Q1-14 MPXHZ9250AC6T kpa Port Now Q2-14 MPXHZ9400A6T kpa No Port Now Q1-14 MPXHZ9400AC6T kpa Port Now Q2-14 MPY8600DK6T1 Tire pressure monitoring system kpa S08, 8 Bit MCU, 16k Flash, 512 b Ram RF transmitter PLL-based 315/434 MHz, ASK/FSK, Manchester MPL3115A kpa Digital Absolute Pressure Sensor Web Now 1.43 Altimeter Compensated sensor Direct readings in Pressure, Altitude and Temperature Typical 25 cm altimeter resolution Embedded software providing real data Embedded interrupts and pre-programmed functions 3 x 5 x 1 mm LGA package Sport Watch Medical Monitoring Breath Analyzer Air Conditioning 21

22 MPX10/12/ kpa SOP, Unibody MPX2 Series kpa ChipPak, Unibody MPX7 Series ±2...±25 kpa SOP MPX4 Series kpa SOP, SSOP, Unibody D G A D G V D G A D G MPX5 Series A D G V kpa SOP, SSOP, Unibody MPX6 Series kpa SOP, SSOP A Uncompensated High sensivity analog output Need external circuit for compensation and amplification Temperature Compensated Integrated temperature compensation Need external circuit for amplification Integrated Pressure Sensor Integrated signal conditioning for temperature compensation, linearization and amplification Package Examples A Absolute D Differential G Gauge V Vacuum MPL115 (Digital I 2 C) A 115 kpa Smart Baro/Pressure 3 x 5 mm LGA SOP Basic Case SOP Side Port SOP Axial Port Unibody Dual Port SSOP Basic Case Medical ChipPak Case LGA 3 x 5 mm Case 22

23

24 Accelerometer + Magnetometer Fused Data Accelerometer plus magnetometer can provide device orientation and magnetic heading. A magnetometer can also be used as a virtual gyro in certain situations (magnetically clean and stable environment). Major weakness of this sensor pair is its sensitivity to linear acceleration, which leads to errors in both orientation and heading. Accelerometer + Gyroscopes Fused Data Accelerometer can help stabilize the drift in the gyroscope output data Rotation and linear acceleration can be separated Major weakness of this pair is the lack of an absolute heading reference Accelerometer + Gyroscope + Magnetometer Fused Data This combination of sensors can overcome the inherent limitations of each of the previous sensor pairings as their error sources (deficiencies) complement each other. Accelerometer + Gyroscope + Magnetometer + Pressure Fused Data This combination of sensors further improves on the previous pair with the addition of elevation. This is essential for use within buildings to sense the floor you are on. The pressure sensor can also be used to enable weather prediction. 24

25 Configure, Power State, Data Control Pressure 3-Axis Acc FoR mapping Trim Trim hi/low/band pass filtering hi/low/band pass filtering Shake detection Pressure shake event Acc x,y,z 3-Axis Gyro FoR mapping Trim hi/low/band pass filtering ω x,y,z 3-Axis Mag FoR mapping Trim & Hard/Soft compensation Raw data calibration parameters hi/low/band pass filtering B x,y,z Sensor Hub Functions FoR = Frame of Reference Mapping Calculate hard/soft iron parameters Kalman Filter or similar function Geometric computations Rotation matrix Quaternion Tilt-compensated mag heading Inclination (φ, Θ, Ψ) Sensor Fusion 25

26 Sensor Hub (FXLC95000CL) A Sensor Hub controls the communication, power, and state of the individual sensors in the system but acts more as a pass through of the data. Sensor Hub and 6-axis Sensor Fusion (FXLC95000CL) A 6-axis Sensor Fusion Solution takes in the data from 2 sensors and provides a calculated output that is calibrated, compensated and calculated but pass through for additional sensors. Sensor Hub with Full Sensor Fusion (Kinetis) A full Sensor Fusion Solution takes in \data from 3 or more sensors and provides a calculated output that is calibrated, compensated and calculated depending on the sensors in the system. Provides a single unified interface for sensor data regardless of sensor types Enables developer to concentrate on using sensor data, not getting sensor data Eliminates intensive sensor integration effort Provides power management of the platform to achieve lowest power mode of operation Create applications with ANY market available sensor Sensor Hub Functionality+ Partial data reduction, with partial data pass through Calibration and Compensation such as: Ecompass Calibration and Compensation Algorithms Gyro drift calibration Virtual gyro with mag and accel for lower power modes of operation Matrix calculations to determine position and orientation of a device within an earth frame of reference requiring: Quaternion Euler Angles Rotation Matrix Calibration and Compensation such as: Ecompass Calibration and Compensation Algorithms Gyro drift calibration Virtual gyro with mag and accel for lower power modes of operation 26

27 Demo Tilt compensated ecompass with best in class hard and soft iron calibration Available in 3 versions: 1. Hard iron only 2. Hard iron and on-diagonal soft iron scale terms 3. Full hard and soft iron calibration (1) and (2) are available in source form via click through licenses at the URL below. (3) is available under NDA Freescale Xtrinsic e-compass sensor fusion software has been awarded Product of the Year by Electronic Products Magazine 27

28 Xtrinsic sensor fusion in tablets, slates, convertible/non-convertible laptops and other portable devices Won the China Annual Creativity in Electronics (ACE) Sensor/Analog Signal Conditioning Product of the Year for 2013 HID/USB Reference design includes both hardware and software components required to easily add sensor fusion capabilities to existing designs 28

29 Demo Educational variant of tool used internally for algorithm checkout. Experiment with various fusion techniques using the sensors already in your Android device Available today on Google Play. Search for Sensor Fusion. 29

30 Available Now Differentiating Points Industry s First open Intelligent Motion Platform Framework Sensor hub capability Power management features enabling low power modes Product Features Provides a single unified interface for sensor data regardless of sensor types Enables developer to concentrate on using sensor data, not getting sensor data. Eliminates intensive sensor integration effort. Provides power management of the platform to achieve lowest power mode of operation Typical Applications Mobile: Phones, Tablets, ereaders Controllers: Remotes, Game Sports Monitoring Performance Monitoring Augmented Reality Xtrinsic Intelligent Sensing Framework Simplified Pwr Mgmt APIs Power Manager LEGEND: Pub/Sub Event-based Sensor Data Sensor Manager Sensor Abstraction Interface Internal Sensor Adapter Sensor Configuration ISF Components Sensor Adapter Sensor Data Updates ISF Abstraction Interfaces Embedded Application Embedded Application Embedded Applications Sensor Adapter Bus Manager Intelligent Sensing Framework MQX RTOS Intelligent Sensor Hardware ISF Sensor Extensions ISF Bus Protocol Extensions Registered Callbacks - OR - Command Interpreter Device Messaging Other Freescale SW I/O Buffers Host Proxy Protocol Driver Protocol Driver I2C Hardware Protocol Driver INT_OUT Customer Developed Host Processor External Sensor External Sensor External Sensor 30

31 31

32

33 Xtrinsic Sensing Development Tools Sensors EVKS Tower and Sensors Part Number RD4247FXOS8700 RD4247MAG3110 KITFXLC95000EVM KIMA9550LEVM DEMOSTBMPL3115A2 Description FXOS Axis Development Board MAG3110 Development Board FXLC95000 Development Board MMA955xL Smart Sensing Platform MPL3115A2 Development Kit B- Bluetooth C- Combo D- Discrete H-HUB Part Number Description KITSTARTER2EVM Sensor Tool box starter kit to support Acceleratometer, Presure and touch sensing MMA8451/2/3Q, MPL115A1, MPR121 KITSTBLITE2EVM Sensor Tool Box kit 2 (demo boards only) KITSTARTER1EVM Sensor Toolbox Starter Kit 1 RDMMA865x Sensor Toolbox Bundle for MMA865xFC Accelerometer LFSTBPROTO Prototyping board KIPR03xEVM MPR03xEVM Development Kit KIPR121EVM MPR121EVM Development Kit 33

34 community.freescale.com/community/sensors Forum for customers and Freescale experts to exchange technical information about Freescale solutions In this vibrant, best-in-class environment, you can share sensor design ideas and tips, ask and answer technical questions, and receive input on just about any sensor design topic. Technical support with fellow design engineers and Freescale experts 34

35 Sensors Sensor Products (in Q4 13) Blogs: Smart Sensors What in the world is contextual sensing? Evolving intelligence with sensors Magnetic sensor makes electronic compass design easy 35

36

37

38 Medical targeted Applications Activity monitoring device (ultra low power Accelerometer MMA8491Q) Hospital bed (High precision Tilt MMA8451) Invasive Blood pressure monitors (MPX Bio-medically approved) Non Invasive Blood pressure monitors (Pressure MPX2051GS, MPXV5050G+MMA8451 ) Electronic Alcohol breathalyzer (Digital pressure sensor MPL3115 ) Sleep apnea (CPAP machines MPXV5004G) Inhalers and ventilators (digital pressure MPXV5004, MPL3115) 38

39 Application specific requirement: Low power (replaceable battery: 3-5 years life time) Accelerometer sampling frequency between 1hz 25hz Reasonable sensitivity 1 mg/lsb Low voltage, small form factor Freescale unique solution MMA8491Q (in the HHH reference design): 0.35 µa/ Hz: best in class up to 20Hz. 1 mg/lsb 1.95V-3.6V supply voltage range 3x3mm QFN package New Best in class power consumption 39

40 UNIQUE MMA8491Q Host MCU triggers Sensor Host MCU powers-up MMA8491Q for a Measurement Slot Classical accelerometer Sensor wakes up Host MCU MMA845xQ raises INT line when data ready Host Processor Enable I2C MMA8491Q Host Processor Interrupt I2C MMA845xQ Power 1 Hz: 0.6µA 0.35µA Power 1 Hz : 10nA 6µA Total = 0.95 µa Total = 6 µa 40

41 Industrial targeted Applications METERING Physical tamper detect (Tilt sensor MMA8491Q) APPLIANCE Load unbalance & water level detect (FXLS8471Q + MPXV5004G) HIGH PRECISION TILT MEASUREMENT (MMA8451Q, MMA9559, FXLN83xx) VIBRATION MONITORING (MMA9559, FXLN83xx) 46

42 Demo Application specific requirement : Physical tamper detection Improved reliability vs mechanical tilt solution (ball in a box) Extreme low power, low g Easy to use, direct tilt measurement Freescale unique solution MMA8491Q: 2/4/8g configurable range 400nA/Hz power consumption 3 logic output to give tilt threshold indication 45 TAMPER 3xI/O s MMA

43 Application specific requirement : Low g - 2g Good sensitivity and low noise Good stability in temperature Angular error < 1 over -40 ;+85 C Freescale unique solution MMA8451 / MMA955x / MMA6900Q : 2/4/8g configurable range Ultra low noise 99 µg/ (Hz) for MMA8451 & MMA955x TCO = 0.15 mg/ C for MMA8451 Angular error around +/- 0.5 peak for MMA8451 at fixed temp Angular error around +/- 0.2 peak for MMA9559 at fixed temp Temperature effect provides additional +/- 3 over 20;+40 C with MMA8451 Temperature effect provides additional +/- 1 over 20;+40 C with MMA6900Q Tilt firmware with Arctan calculation can be embedded in MMA9559 flash memory Tilt sensor turn key solution 48

44 Application specific requirement : Vibration monitoring and control for drill speed control and better user experience High bandwidth from 1kHz to 3kHz depending on the use cases Very high signal noise ratio (high sensitivity & low noise) Freescale unique solution FXLN83x1 2g configuration preferred for better sensitivity High bandwidth up to 4.9kHz on Z axis and 2.1kHz on XY axis for FXLN8371 and higher noise ~ 250 µg/ Hz Mid bandwidth up to 1.7kHz on XYZ and lower noise ~ 150 µg/ Hz High sensitivity up to 229 mv/g on 2g mode. 49

45 Consumer targeted Applications CELL PHONE: MMA865x, MAG3110, FXOS8700CQ (orientation & e- compass) TABLET: MMA865x, MAG3110, FXOS8700CQ, MPL3115A2 (orientation, e-compass, altimeter) GAMING: FXAS21000, MMA8491, MMA845x, MMA865x REMOTE CONTROL : FXAS21000, MMA8491, MMA845x, MMA865x 50

46 Application specific requirement: Reduce system power Increase MCU sleep time while monitoring the activity Freescale unique solution with the high resolution FIFO: MCU power consumption MCU always awake for real time data pulling + MMA845x at ODR 200 Hz No FIFO MCU power consumption MCU wake up for FIFO data flush MCU in sleep mode until FIFO is full + MMA845x at ODR 200 Hz FIFO = 91% current saving 8 bits MCU wake current consumption = 12 ma 8 bits MCU sleep current consumption = 0.6 ma Veyron ODR = bits 51

47 Application specific requirement : Be flexible on choosing low noise configuration or low power Get the best trade-off on these 2 parameters Freescale unique, trade-off selectable modes : Consumption is linked to different parameters : Oversampling ratio (between 2 to 1024) : OS, power consumption Output data rate (between 1.56Hz to 800Hz). ODR, power consumption Power consumption α ODR x OS α ADC internal sampling frequency Noise is linked to oversampling ratio: OS ratio, noise level Hence, at a fixed ODR, decreasing the noise means increasing power: TRADE- OFF Oversampling Scheme : 52

48