FreescaleMMA845X三轴14位数字加速度计解决方案

FreescaleMMA845X三轴14位数字加速度计解决方案关键字：工业控制,传感器,加速度计Freescale公司的MMA8451Q是14位/8位智能低功耗三轴数字加速度计,工作电压1.95V-3.6V,接口电压1.6V-3.6V,动态可选择满刻度为±2g/±4g/±8g,输出数据速率(ODR)从1.56Hz到800Hz,噪音为99ug/√Hz,14位和8位数字输出,I2C数字输出接口,主要用在电子罗盘,静态方向检测,笔记电脑,电子阅读器,实时方向检测(如3D定位反馈)和实时行为分析(如计步器).本文介绍了MMA8451Q主要特性,方框图,应用框图以及MMA845X传感器加速度计板LFSTBEB845X电路图和元件布局图.3-Axis,14-bit/8-bitDigitalAccelerometerTheMMA8451Qisasmartlow-power,three-axis,capacitivemicromachinedaccelerometerwith14bitsofresolution.Thisaccelerometerispackedwithembeddedfunctionswithflexibleuserprogrammableoptions,configurabletotwointerruptpins.Embeddedinterruptfunctionsallowforoverallpowersavingsrelievingthehostprocessorfromcontinuouslypollingdata.Thereisaccesstobothlowpassfiltereddataaswellashighpassfiltereddata,whichminimizesthedataanalysisrequiredforjoltdetectionandfastertransitions.Thedevicecanbeconfiguredtogenerateinertialwake-upinterruptsignalsfromanycombinationoftheconfigurableembeddedfunctionsallowingtheMMA8451Qtomonitoreventsandremaininalowpowermodeduringperiodsofinactivity.TheMMA8451Qisavailableina3mmx3mmx1mmQFNpackage.MMA8451Q主要特性:•1.95Vto3.6Vsupplyvoltage•1.6Vto3.6Vinterfacevoltage•±2g/±4g/±8gdynamicallyselectablefull-scale•OutputDataRates(ODR)from1.56Hzto800Hz•99ug/√Hznoise•14-bitand8-bitdigitaloutputpull-up)•I2Cdigitaloutputinterface(operatesto2.25MHzwith4.7kohm•2programmableinterruptpinsfor7interruptsources•3embeddedchannelsofmotiondetection–FreefallorMotionDetection:1channel–PulseDetection:1channel–JoltDetection:1channel•Orientation(Portrait/Landscape)detectionwithprogrammablehysteresis•AutomaticODRchangeforAuto-WAKEandreturntoSLEEP•32sampleFIFO•HighPassFilterDataavailablepersampleandthroughtheFIFO•Self-Test•RoHScompliant•CurrentConsumption:6uA–165uAMMA8451Q典型应用:•E-Compassapplications•Staticorientationdetection(Portrait/Landscape,Up/Down,Left/Right,Back/Frontpositionidentification)•Notebook,E-ReaderandLaptopTumbleandFreefallDetection•Real-timeorientationdetection(virtualrealityandgaming3Duserpositionfeedback)•Real-timeactivityanalysis(pedometerstepcounting,freefalldropdetectionforHDD,dead-reckoningGPSbackup)•Motiondetectionforportableproductpowersaving(Auto-SLEEPandAuto-WAKEforcellphone,PDA,GPS,gaming)AO-Electronics傲壹电子官网：中文网：•Shockandvibrationmonitoring(mechatroniccompensation,shippingandwarrantyusagelogging)•Userinterface(menuscrollingbyorientationchange,tapdetectionforbuttonreplacement)图1.MMA8451Q方框图图2.MMA8451Q应用框图LFSTBEB845X:MMA845X传感器加速度计板TheLFSTBEB845XisanevaluationboardfortheFreescaleMMA845Xfamilyof3-axishighperformance,highfunctionalitylow-gaccelerometers.TheLFSTBEB845Xkitincludesdaughterboardsforeachofthethreedevicesinthisfamily:MMA8451Q,MMA8452Q,andMMA8453Q.ForcustomersalreadyfamiliarwiththeSensorToolboxPlatform,theLFSTBEB845XisdesignedtoworkwiththeLFSTBBAT9forpowerorLFSTBUSBforcommunicationtoaPC.ThedevelopmentkitRDMMA845XcomeswithboththeLFSTBEB845XandtheLFSTBUSBboardstogetherforevaluatingalloftheembeddedMMA845Xfunctionality.LFSTBEB845X包括:OneAccelerometerDevelopmentBoardOneMMA8451DaughterBoardOneMMA8452DaughterBoardOneMMA8453DaughterBoardUSBCableQuickStartGuide图3.LFSTBEB845X传感器加速度计板外形图图4.LFSTBEB845X电路图图5.LFSTBEB845XMCU电路图图6.LFSTBEB845X板元件布局图图7.MMA8451Q电路图图8.MMA8452Q电路图图9.MMA8453Q电路图