ExternalComponentsFall2017
6.111
Wherewewere…wherewe’regoing• Everyoneknowsandlovestomisquote
Moore’sLaw
• ComputationalPowerhasindeedgrown
exponentiallyinthelasthalf-century
• Alongwiththat,lurkinginthedepths,hasalsobeenaremarkabledevelopmentof
fully-integratedsystemsthatwe’vereally
onlystartedtoseebreakoutinthelast
~15years.
https://en.wikipedia.org/wiki/Moore%27s_law
Whatwasthecomplexityofasinglepartthatyoucouldbuy?
SingleActive,PassiveComponent
ceaselessprogressionoftime
LSIàMSIàLSIàVLSIàVLSII
MultipleActiveComponentsMicrocontrollers
ComputationalDomainSensingDomain
SingleSensors SingleSensors SingleSensors MEMSforsale
Hybrid
FullSOCs
IntegrationProvidesRobustness• Muchof20
th
centuryfocused
onintegrationatthe
electrical/computationallevel
• Lastfewdecadessawfurtherintegrationinwithsensors,
actuators,communication
modules,etc…
• EmergenceofrealSOCs
GermanVCL11,1938:twotubesinonetube!
1950sOpAmpfromGeorgePhilbrick Assoc (Boston)
7400SSIIntegratedCircuit
8080MCU
iPhone4(gyro)
http://eecatalog.com/sensors/2012/05/24/mems-trends-smaller-cheaper-everywhere/
ESP32SOCFunctionalityBlocks
CaseStudy(MEMSSOC):Accelerometers:
• FirstMEMSaccelerometer:late 70s
• ADXL50:(AnalogDevices1991)(singleaxisin25mm2
)
• ADXL335:AnalogOutAccelerometer (1998)
• Voltages forthree axes ofacceleration• MMA8452Q:DigitalAccelerometer(mid2000’s)
• MPU925Xseries(orLSM9DS1)series(lastfewyears):
• 9DOF(Accel,gyro,compass)
• Onboardsensor-fusion,orientationintegration,DSPengine• In-builtpedometry,cyclemotiondetection,etc…
ADXL335MMA8452Q
MPU9250
1950sSovietAccelerometer
CaseStudy(Analog):High-voltageAmplification
• APEXPA3440High-voltageOperationalAmplifier:
• 340VDCsupplylimit
• 120mAoutputcurrent
• Wherebeforeyouneededtodesignanentire
circuitandworryaboutcapacitiveloading,death,
younowcanbuythisfor$11.00anddriveaPiezo
prettyeasily
PartsofInterest
SmallDisplays:• TFTsThin-FilmTransistors:
• color• OLEDs(OrganicLight-EmittingDiodes):
• Faster• Betterviewingangle,colors,efficiency
• Ifyouwanttoanimateanything,ifpossiblegetanSPI
interface:
• i2Cistooslowtogivesufficientlyhighspeed
• Don’tforgetcomputermonitor(isasmalldisplaycore
toyourproject?)
RandomTFToffofAmazon
CheapMonochromeOLEDusingSPI
ColorOLEDfromAdafruit
TouchScreens
• Resistive:• Accessedusinganalogmeasurements
(sometimesdigitalreadout)
• Usuallyonlyonepointofcontactallowed• Generallysuck..those earlyandroidtabletswiththemwereborderlineunusable
• Capacitive:• Accessedviai2c,SPIregisters• Moreadvancedchipsetshavein-builtgesture
detection(swipes,etc..)inadditiontotouch-
points
• Actuallywork
FT6X06-familybasedtouchscreen
Random-resistive
TouchscreenfromAmazon
EnvironmentalSensors
https://www.tindie.com/products/onehorse/air-quality-sensors/
CCS811GassensorBME280pressure/temp/humidity
GUVA-S12SDUVSensor• Lotsofsingle-chipenvironmentalsensors
available:
• UV• Temp/Pressure/Humidty
• Smoke
• Gasses• ParticulateMatter
• Single-chipspectrometers…probablyoverkillforus
(doRGBextractionfromcamerapixels),butwant
toshowitsinceitiscool
• HamamatsuC12880MA
• ($400,butwecandream)
C12880MA
MiCS-6814 (allinonedevice!):
Accelerometers/IMUs
• Bothdigitalandanalogmodels
available.Reallycheap
• Orientation(usinggravityandcompass)Determination
• RelativeMotionDetermination
ADXL335
MPU9250
Time-of-FlightSensors• Cheap,shorter-rangeLiDAR(couplemetersmax)
• VL53L0XbySTMicro
• SThasthebigpatentsinthisfield• Usedcurrentlyinproximitydetectiononphones,
etc…
• ~$10.00• ~1cmresolution(10picoseconddifferenceinlight
return)
BreakoutfromPololu
VL53L0X
• FunctionGeneratorsonachip• AD9850 DDS:DirectDigitalSynthesis:• Cancreatesinewaves,squarewavesfrom
0to40MHzviadigitalcontrolveryquickly
• Phase-shiftcontrolaswell!• AD9833:SlightlydifferentversionofAD9850,SPIcontrolled,capableof0.004
Hzresolutionfrom0to500kHzwithright
settings/0.1Hzresolutionupto40MHz
AD9850DevBoard
AD9833DevBoard
DDSModules
Cameras
• OV7670ish Series:• Thereshouldbesomebasicmodulesthatalreadywork
withthis
• OthervariantsexistOV2640,*should*beabletogofaster…lookingatcommunicationwithitnow.
• Tonsofothers
OV7670
OV2640(wSPIinterface)
RawOV2640(shouldbeabletoget60fpsoutofthiswithsubsampling)
MT9M001Infrared Camera
SpecialtyImagers• LineScanDevices:• 128x1pixelarray
• Motion/ThermalDetectionDevices
https://www.tindie.com/products/AP_tech/tsl1401cl-linescan-camera-/
LineScanCamera
https://www.tindie.com/products/onehorse/calipile-tpis1s1385-presence-and-motion-detector/
TPiS 1S1385/5029
AMG8833ThermalImager• 8x8thermalsensorarray
• EffectivelyaLow-rescamerathatworksoffof
thermalintensity
• $40currently AMG8833(fromtindie)
OpticalFlowSensors• Basicallylikelong-rangeopticalmice
• (manyfeetwithalens)
• PWM3901isagoodone,usesSPI
communicationandcanmake/give
measurementsat~100Hz
• Greatbecausetheyprovideanconvenientmeansofdeadreckoningwithsub-inch
resolutionwhichcannotbefixedusingIMU
mathorcurrentGPS
https://www.tindie.com/products/onehorse/pmw3901-optical-flow-sensor/
BoardwithcombinedPMW3901andVL53L0X
(opticalflowanddistance)
WirelessCommunication
• Bluetooth:HC05modulesaredesignedto
takein/putoutUART(seriallikefromLab02B)
andchipsethandlesconversions(goodupto
~50ft ormorewithLOS)
• Infraredisreliableovershortdistances…(needLOS)
• NordicSemiconductorsmakessomedevices
thathavefloodedthemarketwiththeirown
brandof2.4GHzbrandcommunication
(popularfromArduinocommunity)
HC-04/5/6Bluetoothseries
InfraredTX/RXpairs(fromLab5)
NRF24L01
Microphones
• ElectretandMEMScapacitive
microphonesarestandardnow
• EitheruseanalogoutORmodelsthat
digitizeon-chip(usuallyconvertintoI2S
whichisastandardaudio-information
digitalcommunicationprotocol…we’ll
discussnextTuesday)
Electretwithselectablegain(Adafruit)
https://www.tindie.com/products/onehorse/ics43434-i2s-digital-microphone/
ICS43434DigitalOutputMicrophone(Invensense),usesi2sprotocol
AudioOut
• Analogori2samplifiers,DACs,etc… are
available.
• MostDACshavei2sinputs,andmanymodern
electronicdevicesconvertaudioinformation
immediatelyto/fromi2s
• Ifyou’reconsideringanaudioprojectmight
beaneatprotocoltolookinto(althoughthe
AC97-setupontheolderlabkits workswell
too)(Vivado hasani2score)
MAX98357A-basedboard from Adafruit:3WClassDaudio amp i2sinput
ComputerInterfacing• We’vealreadyexploredthisinLab2BwithUSB-to-
RS232interfacing
• Nexys4supportsUSBslavemode(haven’ttested
driversyet)
• AlsohaveacollectionofFTDIconverters(convertUSBto/fromUART(serial-readable)
• Usetoolslikethesetohelpputtestcases,exampledata,recordoutputs,etc…
FTDIconverter(BrokenoutUSBtoUART)
ThingstoConsider• LevelShifting?:• Nexys4DDRrunsat3.3V• Somesensorsrunat5V
• Othersrunat2.7V• Check!Mayneedtouselevelshiftersandtheseaddtheirowndelay/skewtosignalsso
beawarewithhigh-speeddatatransfers
• Whenbuying,checkthedatasheets.Foreverywell-documentedversionof
somethingthereare“clones”/variants/obscurechipsetsthatarealsosoldand
areoftencheaper.
• Yourprojectshouldbecomplexbutdoyouwanttofocusonthecomplexity
ofasensororaprotocolorahigherlevel?
• FPGAsareneat*todevelopwithbecausethere’sgenerallynotado_everything() likeyou’llseewhenworkinginregularArduino-family
devices.Makelemonsintolemonades…moreopportunitytoreaddata
sheets,
*alsofrustrating
RandomProjectIdeas(WhatI’ddoifIwereyoung)
• RebuildApolloGuidanceComputer(AGC):
• Sourcecodehere:https://qz.com/726338/the-code-that-took-america-to-the-moon-was-just-
published-to-github-and-its-like-a-1960s-time-capsule/
• Schematicshere:http://klabs.org/history/ech/agc_schematics
• Realonewasimplementedusingnothingbut3-inputNORGates!
• ImplementaNeural-Net/SomekindofAssisted/Unassistedlearning:
• FPGAshavebenefitofparallelizability
• Somedecentreposouttheretogetstarted/serveasinspiration
• ClassifysomethingswithoutthecrutchofTensorFlow,numpy,etc…
• Noise-CancellationusingDSP:• Don’tneedtorelyonfeedbackonlyoftoget6dBofsuppression
• FFTsandcutoutthenoise
MargaretHamilton,DirectorofSoftwareEngineering
ApolloProgram,1967