Table Of ContentACSP · Analog Circuits and Signal Processing
Dima Kilani · Baker Mohammad
Mohammad Alhawari · Hani Saleh
Mohammed Ismail
Power
Management
for Wearable
Electronic
Devices
Analog Circuits and Signal Processing
SeriesEditors:
MohammedIsmail,Dublin,USA
MohamadSawan,Montreal,Canada
The Analog Circuits and Signal Processing book series, formerly known as the
Kluwer International Series in Engineering and Computer Science, is a high level
academicandprofessionalseriespublishingresearchonthedesignandapplications
of analog integrated circuits and signal processing circuits and systems. Typically
per year we publish between 5–15 research monographs, professional books,
handbooks,editedvolumesandtextbookswithworldwidedistributiontoengineers,
researchers,educators,andlibraries.
Thebookseriespromotesandexpeditesthedisseminationofnewresearchresults
and tutorial views in the analog field. There is an exciting and large volume of
research activity inthe field worldwide. Researchers are strivingtobridge the gap
between classical analog work and recent advances in very large scale integration
(VLSI) technologies with improved analog capabilities. Analog VLSI has been
recognized as a major technology for future information processing. Analog work
is showing signs of dramatic changes with emphasis on interdisciplinary research
effortscombiningdevice/circuit/technologyissues.Consequently,newdesigncon-
cepts,strategiesanddesigntoolsarebeingunveiled.
Topicsofinterestinclude:
AnalogInterfaceCircuitsandSystems;
Dataconverters;
Active-RC,switched-capacitorandcontinuous-timeintegratedfilters;
Mixedanalog/digitalVLSI;
Simulationandmodeling,mixed-modesimulation;
Analognonlinearandcomputationalcircuitsandsignalprocessing;
AnalogArtificialNeuralNetworks/ArtificialIntelligence;
Current-modeSignalProcessing;
Computer-AidedDesign(CAD)tools;
AnalogDesigninemergingtechnologies(ScalableCMOS,BiCMOS,GaAs,
heterojunctionandfloatinggatetechnologies,etc.);
AnalogDesignforTest;
Integratedsensorsandactuators;
AnalogDesignAutomation/Knowledge-basedSystems;
AnalogVLSIcelllibraries;
Analogproductdevelopment;
RFFrontends,WirelesscommunicationsandMicrowaveCircuits;
Analogbehavioralmodeling,AnalogHDL.
Moreinformationaboutthisseriesathttp://www.springer.com/series/7381
Dima Kilani (cid:129) Baker Mohammad
Mohammad Alhawari (cid:129) Hani Saleh
Mohammed Ismail
Power Management for
Wearable Electronic Devices
DimaKilani BakerMohammad
KhalifaUniversity KhalifaUniversity
AbuDhabi,UnitedArabEmirates AbuDhabi,UnitedArabEmirates
MohammadAlhawari HaniSaleh
WayneStateUniversity KhalifaUniversity
Detroit,MI,USA AbuDhabi,UnitedArabEmirates
MohammedIsmail
WayneStateUniversity
Detroit,MI,USA
ISSN1872-082X ISSN2197-1854 (electronic)
AnalogCircuitsandSignalProcessing
ISBN978-3-030-37883-7 ISBN978-3-030-37884-4 (eBook)
https://doi.org/10.1007/978-3-030-37884-4
©SpringerNatureSwitzerlandAG2020
Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpartof
thematerialisconcerned,specificallytherightsoftranslation,reprinting,reuseofillustrations,recitation,
broadcasting,reproductiononmicrofilmsorinanyotherphysicalway,andtransmissionorinformation
storageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilarmethodology
nowknownorhereafterdeveloped.
Theuseofgeneraldescriptivenames,registerednames,trademarks,servicemarks,etc.inthispublication
doesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfromtherelevant
protectivelawsandregulationsandthereforefreeforgeneraluse.
Thepublisher,theauthors,andtheeditorsaresafetoassumethattheadviceandinformationinthisbook
arebelievedtobetrueandaccurateatthedateofpublication.Neitherthepublishernortheauthorsor
theeditorsgiveawarranty,expressedorimplied,withrespecttothematerialcontainedhereinorforany
errorsoromissionsthatmayhavebeenmade.Thepublisherremainsneutralwithregardtojurisdictional
claimsinpublishedmapsandinstitutionalaffiliations.
ThisSpringerimprintispublishedbytheregisteredcompanySpringerNatureSwitzerlandAG.
Theregisteredcompanyaddressis:Gewerbestrasse11,6330Cham,Switzerland
Theauthorswouldliketodedicatethiswork
totheirparents,families,andbelovedones
Preface
With the dramatic rise of mobile electronic devices usage especially as an effect
oftheinternet-of-thingsrevolution,thedemandforenergyefficientandsmallform
factorsystemsraisestheneedforlowpowermultisourcemanagementunit(PMU)
forenergystraineddevicesaswellasenergyharvestingasalternativepowersource
in many usage scenarios. Energy harvesting becomes one of the pillars that fulfill
theneedsofultra-lowpowerdevicesinmanyapplicationsincludingtheIoT-based
healthcare.Sincetheharvestedenergydependsontheavailabilityofvarioussources
from the surroundings, a power management unit (PMU) is required to efficiently
regulatetheharvestedenergy.
Power converters and voltage regulators are important building blocks in the
PMU in order to interface between the energy harvesting and the system on
chip (SoC). Different types of energy harvesting source require different power
converters. This depends on the electrical signal obtained from the harvester,
harvester size, and efficiency. In addition, the selection of the voltage regulator
depends on the area of the whole device and the requirements of various blocks
intheSoCsuchasmemory,hardwareaccelerator,analogfront-end,andRF.Hence,
sophisticatedPMUcircuitsandtechniquesarerequiredtoenablethedevelopment
ofthestate-of-the-artenergyharvesting-basedPMUincludingpowerconvertersand
voltageregulators.
Toaccomplishthisneed,thisbookprovidesacomprehensivepowermanagement
circuit design that targets low power wearable electronic devices powered by a
thermoelectric generator (TEG) source, a battery or both. This includes extensive
literature review about power converters and voltage regulators in addition to
experimental results from silicon. This book is organized into 6 chapters. Each
chapter carries a brief introduction of the work undertaken and is followed by the
detailedcircuit,results,andanalysis.
Chapter1providesdetailedbackgroundaboutthepowermanagementtechniques
attechnology,circuit,andsystemlevelanddeliversanoverviewoftherecentenergy
harvestingsourceutilizedforwearableelectronicdevices.
Chapter2discussesthebasicconceptoftheTEGdeviceandmodelandhowit
can harvest the thermal energy based on the Seebeck effect. Further, it provides a
vii
viii Preface
comprehensive literature review about the interface circuits required by the TEG-
based PMU such as power converters, startup circuits, voltage regulators, and
maximumpowerpointtrackingtechnique.Inaddition,itpresentsthestate-of-the-
artTEG-basedPMUdesignsthatareavailableintheliterature.
Chapter 3 focuses on the characterization of the system level TEG-based PMU
using several design options of power converters and voltage regulators. The
characterizationintermsofpowerefficiency,voltageripple,andareaarebasedon
measurement results in 65nm CMOS technology which guides the researchers to
selecttheproperPMUdesignbasedontheblocks’requirementswithinthedevice.
Chapter4highlightsthestate-of-the-artmulti-outputsswitchedcapacitorvoltage
regulators. Then, it discusses a dual-outputs switched capacitor (DOSC) voltage
regulator using a single switched capacitor design in order to minimize the area
ofPMU.Ithighlightshowthecontrolcircuitofadaptivetimemultiplexingcanbe
usedtogeneratetwooutputvoltagelevelsandeliminatethereversecurrentproblem.
Measurementresultsareshownin65nmCMOStechnology.
Chapter5providesadetailedliteraturereviewontheavailabledigitallowdrop
out (LDO) regulator. Then, it introduces a clock-less digital LDO regulator based
onaratioedlogiccomparator(RLC).Simulationresultsareshownin22nmFDSOI
technologyandacomparisonwithpriorworkondigitalLDOisillustrated.
Finally, Chap.6 concludes this book and presents possible directions for future
workinthisareaofresearch.
AbuDhabi,UnitedArabEmirates DimaKilani
Acknowledgments
The work in this book has its roots in the doctoral dissertation of the first author.
We would like to thank and acknowledge all those who assisted us with the
different phases ofdeveloping the materialthatled tothisbook. We would liketo
specificallyacknowledgeallmembersofoursystemonchipcenter(SoCC)fortheir
help, encouragement, and support, Dr. Mihai Sanduleanu, Dr. Temesghen Habte,
AhmedAli,NoraHarb,HudaAlbanna,Yonatankifle,andDanCracan.Theauthors
acknowledgetheaccesstotheSoCCfacilitiesforconductingtheexperimentalwork
andtestingthechips.Finally,wewouldliketoacknowledgethehelpandsupportof
ourfamiliesandfriendsandthankthemfortheirpatienceandunderstanding.
AbuDhabi,UnitedArabEmirates DimaKilani
AbuDhabi,UnitedArabEmirates BakerMohammad
Detroit,MI,USA MohammadAlhawari
AbuDhabi,UnitedArabEmirates HaniSaleh
Detroit,MI,USA MohammedIsmail
ix
Contents
1 IntroductiontoPowerManagement....................................... 1
1.1 LowPowerWearableElectronicDevices.............................. 1
1.2 LowPowerManagementTechniques.................................. 3
1.2.1 DynamicPowerReduction..................................... 3
1.2.2 LeakagePowerReduction...................................... 5
1.3 EnergyHarvesting-BasedDevice ...................................... 9
1.4 AimandObjectives..................................................... 11
References..................................................................... 12
2 IntroductiontoTEG-BasedPowerManagementUnit .................. 15
2.1 IntroductiontoTEG..................................................... 15
2.2 InterfaceCircuitofTEG................................................ 17
2.2.1 StartupCircuit .................................................. 17
2.2.2 DC–DCBoostConverter....................................... 18
2.2.3 MaximumPowerPointTransferTechniques.................. 20
2.2.4 VoltageRegulator............................................... 21
2.3 ExistedTEG-BasedPowerManagementSolutions................... 25
References..................................................................... 28
3 TEG-BasedPowerManagementDesignsandCharacterizations ...... 31
3.1 ProposedTEG-BasedPMUArchitecture.............................. 31
3.1.1 SwitchedInductorBoostConverterCircuitDesign........... 33
3.1.2 SwitchedCapacitorRegulatorCircuitDesign................. 33
3.1.3 LDORegulatorCircuitDesign................................. 35
3.2 TEG-BasedPMUMeasurementsin65nmCMOS.................... 36
3.3 SummaryandRecommendations ...................................... 45
References..................................................................... 46
4 Dual-OutputsSwitchedCapacitorVoltageRegulator................... 47
4.1 StateoftheArtDual-OutputsSwitchedCapacitorVoltage
Regulator ................................................................ 47
xi
