Smart Grid Solutions Guide - Maxim

Smart Grid Solutions GuideTable of contentsTable of contentsIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Smart metersOverview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Featured products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Recommended solutions table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Power-grid monitoringOverview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Featured products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Recommended solutions table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22CommunicationsOverview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Featured products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Recommended solutions table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Energy measurementOverview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Featured products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44Legal notices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47www.maxim-ic.com/smartgridiii

Smart Grid Solutions GuideivMaxim Smart Grid Solutions

Smart Grid Solutions GuideIntroductionMeeting future energy challenges todayThe smart grid represents a newvision for how we can harnesstechnology to renew energyinfrastructure, redefine our responsibilitiesas energy users, and,ultimately, conserve vital energyresources.Smart grid architects face manychallenges in realizing this vision, notleast of which is choosing solutionsthat offer a cost-effective upgradepath. The sheer scale of this infrastructuralchallenge necessitates awell-defined strategic roadmap. Toavoid stranding assets, the selectedsolution must be both compatiblewith the existing infrastructure andscalable to meet future needs.System designers must keep up witha constantly changing regulatorylandscape. This task can be greatlyeased by choosing a solutionspartner who understands therequirements of different countries,and works closely with industryconsortia to develop standards.Maxim is a proven leader insmart energyMaxim has long been regarded as aleader in power-saving technology.Over the years, we have pioneerednew techniques for battery management,high-efficiency powerconversion, and low-power design.Today we are applying our expertiseto smart energy applications,including energy metering andmeasurement, power-distributionautomation, smart grid communications,hybrid automobiles, and LEDlighting.In 2010, we expanded our smartgrid offering through the acquisitionof Teridian Semiconductor.This acquisition firmly positionsMaxim as the technology leader forenergy metering and measurement.With more than two decades ofexpertise and 50 million ICs shipped,Teridian has defined the leadingedge of the system-on-chip (SoC)energy-measurement market. Systemdesigners worldwide use these SoCsto accelerate system developmentand reduce engineering costs fornew energy-metering and measurementapplications.Maxim’s powerline communicationstechnology (G3-PLC) is enablingnew smart grid applications aroundthe world. G3-PLC is currently beingdeployed in France to implement anadvanced metering infrastructure forover 35 million customers. It alsoserves as a base technology for internationalstandards development effortssuch as ITU G.hnem/G.9955 andIEEE® P1901.2.Maxim’s PLC and SoC solutions arecomplemented by a broad portfolioof analog and mixed-signal solutions,including power-management ICs,real-time clocks, RF communications,and interface products. All of whichmakes Maxim a true end-to-endsolutions provider for metering andother smart grid applications.A committed innovationpartnerMaxim’s application experts workclosely with system designers todevelop technology platforms thatmeet implementation requirementsfor backwards compatibility, scalability,and compliance with internationalstandards.This solutions guide addresses keychallenges facing smart grid architectsand designers. It details howMaxim’s solutions are enablingcustomer innovations in communications,distribution automation, andenergy measurement and metering.Design with MaximDevelop smarter, more-precisesystems• Proprietary process technologiesyield the tightest tolerances,lowest noise, highest voltage/current capabilities, and greatestintegration• Maxim’s broad product portfolioenables end-to-end solutionsoptimized for performance-drivenapplications• State-of-the-art communicationstechnologies build intelligenceinto grid infrastructure, from thesubstation to the customerpremiseAccelerate your time to market• Benefit from the implementationexpertise that Maxim has gainedwhile working with industryconsortia, utilities, and equipmentmanufacturers• A comprehensive library of applicationnotes, reference designs,and software tools speeds yourdesign projects• Flexible solutions are easily adaptedto meet different internationalstandardsReduce equipment/infrastructurecosts• Advanced integration minimizesyour bill of materials and infrastructurecosts• Application expertise helps youmake the right systemperformance-cost trade-offs• Integrated protections andindustrial-grade temperatureranges ensure that your designsurvives real-world conditionswww.maxim-ic.com/smartgrid 1

Smart metersOverviewSmart metersOverviewUtility companies worldwide havebegun deploying smart meters toservice residential and commercial/industrial markets. Smart metersdeliver a range of benefits includinglower operational and capitalexpenses, support for new services,and improved operational control.Smart meter requirementsDeployment of smart meters is farfrom a “one-size-fits-all” undertaking.Manufacturers must account for thevarying regulatory requirements ofeach region, as well as the differentfunctionalities and services requiredfor different markets.In North America, for example,automated meter reading (AMR)regulations dictate the frequency ofmeter reading and data transmission.They also specify the amount of datathat must be retained locally at anygiven point in time. Because communicationsare not always reliable, someof these regulations require utilitiesto store two or more transmissionsto meet billing requirements. Thisrequirement increases the amountof local on-chip memory needed forsmart meter ICs. As a result, the regulatorypressures of specific jurisdictionshave a direct impact on the design ofsmart meters down to the chip level.Another major driver of smart meterfunctionality is improving localantitampering capabilities. This isespecially important in developingmarkets where electricity theftaccounts for a large percentageof overall power usage. The abilityof solid-state electricity meters todetect and prevent tampering cansignificantly improve control and costrecovery for utility companies. Hereagain, high-level antitamperingobjectives are both driving theadoption of solid-state metering anddictating required feature sets at thechip level.Finally, the promise of improvingservice to customers represents animportant goal of smart metering,especially over the long term. Byenabling customers to better managetheir own energy usage throughincentive-based programs—such asdirect load control, interruptible rateagreements, and demand bidding/buyback—smart metering can helputilities manage overall energyconsumption patterns and cope withpeak-demand challenges. With theright capabilities built into chip-levelsolutions, smart meter deploymentscan effectively lay the groundwork forexpanded customer-service functions,such as wireless integration with thermostatsto automatically adjust usageduring peak-demand periods.ISOLATED/NONISOLATED POWERDC-DCVOLTAGE/CURRENTSENSORSVOLTAGEREFERENCEOPTIONAL EXTREMEACCURACY COMPONENTSACCURATERTCMETERING SoC(ADC/CPU/DSP)TRANSFORMER DRIVERFOR RS-232/RS-485DESIGNSDATACOMMUNICATIONSREMOTE-DISCONNECTRELAYRELAYDRIVERSUPERVISORTAMPERDETECTIONUSERINTERFACEMEMORYMAXIM SOLUTIONSmart meter block diagram. For a list of Maxim's recommended smart meter solutions, please go to: www.maxim-ic.com/smartmeter.www.maxim-ic.com/smartgrid 3

Smart metersOverviewby using higher end functionality forantitampering purposes).There is long-term potential for costsavings by combining the AMRfunctions directly into themetrology SoC. Yet, this is unlikely tobe practical in the near term, dueprimarily to fragmentation of AMRcommunications methodologies.Communication links may be basedon modems (either fixed line orcellular wireless) or powerlinecommunications (PLC), with the BOMcost ranging from $3 for PLC up tomore than $20 for cellular modems.Field programmabilityDeploying higher end metrologychips that allow for field programmability(via firmware) enables utilitiesto bring down both operational andcapital investment costs over thelong term. This extends the useful lifeof the infrastructure and helps tojustify smart metering investmentswithin rate-based calculations.Field programmability gives utilitiesmuch greater flexibility to adjustpolicies in response to changingenergy usage patterns. For example,the specific times of day set forpeak-rate pricing policies may needto be adjusted as significant numbersof users shift their energy consumption,or in response to seasonalfluctuations. Remote upgrades viafirmware allow utilities to quicklytailor their rate incentives forcustomers to help smooth out peakdemand while tracking dynamicchanges in peak-usage patterns.Energy-management servicesSmart metering gives utilities realtimevisibility into usage patterns.Moreoever, it enables them topromote demand-side management,empowering customers to bettermanage their own usage. Forinstance, the Californian utility PG&Eplans to offer customers enhancedoptions such as monitoring theirhour-by-hour usage on the Internetand adjusting their usage to takeadvantage of incentive rates. Inaddition, there are plans for enablingwireless integration of smart meterswith customers’ thermostats. Thiswill allow minor pre-agreed adjustmentsto automatically be made totemperature settings during peakperiods in exchange for an overallrate reduction.Smart metering also opens up thepossibilities for implementing submeteringstrategies within largerbuildings. By using a single smartmeter with multidrop communicationlinks to individual customers,a utility can eliminate the need forindividual meters while still providinga high degree of visibility into eachcustomer’s energy usage.Security mechanismsAntitampering is another key driverfor smart metering, especially indeveloping countries where electricitytheft is a major cost concern forutilities. For example, it has beenestimated that as much as 40 percentof the power usage in Brazil is stolen.Typical tampering techniquesvary from intrusive means suchas breaking the meter housingand jamming the mechanism tomore subtle methods like applyingmagnets to the outside of the meterto saturate magnetic components.Some attempt to alter the characteristicsof the load by addingcapacitance, half-wave rectifiedloads, or instantaneous highcurrents. Others may bypass themeter, wholly or in part, which cancause an increase in the AC currentflowing through the meter’s neutralterminals.Deployment of more sophisticatedsolid-state metrology enablesadvanced antitampering measurementssuch as the reflected load(VAR-hours), neutral current, DCcurrents invoked by rectified loads,and detection of ambient magneticfields. Substation meters may alsobe used to detect discrepanciesbetween the total billed and thetotal generated power and reportthem via an AMR network. In orderto prosecute and recover the costs ofstolen energy, detailed informationsuch as the exact times and amountsof energy theft are critical piecesof evidence that can be capturedthrough smart metering technology.Chip-level feature requirementsfor smart metersSystem on chipIt is clear from the evolving marketrequirements, jurisdictional regulatorydifferences, and varyingimplementation approaches thata single, universal solution is notpossible. However, by using highlyintegrated, flexibly configurable SoCmetering solutions manufacturerscan bring down their R&D costs andimprove their ability to serve theentire range of market requirements.This approach also helps futureproofmeter architectures to meetemerging requirements.Key ingredients of smart meterSoCs include:• Flexible, multiple-port communicationsoptions to support AMRlinks, integration with localdevices such as thermostats,and multidrop submeteringtopologies• Streamlined multiread processingcapabilities such as the SingleConverter Technology approach toreduce unit cost by multiplexinginputs through a delta-sigma ADCin conjunction with a programmablecompute engine• Support for a variety of sensorinputs with minimum hardware;ability to adjust for temperatureand other environmental variationsfor improved efficiency and accuracywww.maxim-ic.com/smartgrid 5

Smart metersOverview• Field-upgradeable firmware toextend the useful life of themetering solution and allowpolicies to be dynamically adjustedto optimize energy usage• Polyphase monitoring and analysiscapabilities to help manage energyconsumption, enable load analysis,and optimize motor functions• LCD interface capable of supportingmultiple voltages and screenresolutions• Various levels of internal flashmemory sizes, along with externalmemory-management capabilitiesto support a wide portfolio of datastorage options• Several tamper-detection mechanismsto prevent energy theft;support for current transformers,Rogowski coils, and current shuntsalong with their combinationalcurrent-sensing mechanisms; opencurrent-sensor detection• Ability to work with single-wirepower measurement for specialtamper-detection conditionsfor single- and polyphase powermeasurements• Built-in real-time clock (RTC)functionalityReal-time clockMany metering AFEs integrate areasonably accurate RTC, which maydrift as much as 60 minutes/year. Thisinaccuracy should not be a problemif the meter is connected to a smartnetwork that periodically resynchronizesthe RTC. If the meter is notconnected to such a network, endcustomers will experience significantbilling discrepancies over time—unless, that is, a highly accurate RTCis used.Maxim has long offered the industry’smost accurate timekeeping solutionsfor metering applications. RTCssuch as the DS3231 monitor anonboard temperature sensor andadjust the load capacitance of anembedded crystal in order tocompensate for the natural temperaturevariation of the tuning forkcrystal. Because the crystal and dieare calibrated across the fulloperating temperature range asa unit, the resulting frequencyaccuracy is better than anycompeting technology. Theseproducts exceed the rigorousstandards for timekeeping accuracyin metering applications and arearmed with a multitude of advancedfeatures. Most importantly, theyeliminate the need for user calibration,providing a highly accuratesolution straight out of the box.Maxim’s new MEMS-based RTC,the DS3231M, extends the benefitsof the DS3231. The device’s allsiliconresonator enables thelow-frequency and low-currentcharacteristics of the crystalbasedDS3231 to be migrated to asmaller package. Additionally, theDS3231M offers extreme resilienceagainst high-temperature assemblyprocesses, can withstand shock andvibration in excess of 20Gs, andincludes offsets for aging.At the heart of the DS3231M is atemperature-compensated siliconoscillator. Based on measurementsfrom the DS3231M’s onboardtemperature sensor, a temperaturecompensationalgorithm automaticallyadjusts the resonantfrequency to account for temperatureeffects. This approach ensuresextremely tight accuracy overtemperature. Unlike crystal-basedproducts, the DS3231M exhibits lessthan ±0.5ppm of frequency shiftafter high-temperature reflows,and it maintains flat frequencystabilitycharacteristics (< ±5ppm)over the entire -40°C to +85°Ctemperature range.SummaryBy leveraging the flexible SoC featureset described above, manufacturerscan effectively address the range ofmetering options—from low-costfixed-function devices to premiumdevices that offer ample memory,reprogrammability, and highaccuracy. As the market for smartmeters continues to evolve, thisflexibility will enable meter manufacturersand utility companies to adaptto the needs of customers and thedictates of regulatory authorities, whilesimultaneously optimizing operationalefficiency and profitability.6 Maxim Smart Grid Solutions

Smart metersFeatured productsEnergy-meter SoCs reduce cost while improving design flexibility and accuracy71M6541D*/41F*, 71M6542F* (single phase)71M6543F*/43H* (polyphase)The Teridian 71M6541D/41F/42F (single phase) and 71M6543F/43H(polyphase) are highly integrated, flexible metering SoCs thatsupport a wide range of residential, commercial, and industrial meterapplications with up to Class 0.2 accuracy. The devices incorporate a5MHz 8051-compatible MPU core and a 32-bit computation engine(CE); a low-power RTC with digital temperature compensation; up to64KB flash memory and 5KB RAM; and an LCD driver. The proprietarySingle Converter Technology architecture includes a 22-bit deltasigmaADC, which provides unmatched linearity performance overa wide dynamic range and consumes less power than a multi-ADCimplementation. Automatic switching between main power andthree battery-backup modes ensures operational reliability. TheseSoCs operate over the -40°C to +85°C industrial temperature range.The 71M6541D/41F are packaged in a 64-pin lead-free LQFP, and the71M6542F/43F/43H are packaged in a 100-pin lead-free LQFP.The 71M6541D/41F/42F and 71M6543F/43H metering SoCs alsofeature a proprietary isolation technology. By using low-cost resistiveshunts and optional interfaces to one of the Teridian isolated sensors(71M6601*, 71M6103*), these metering solutions eliminate theneed for expensive, bulky current transformers. This, in turn, reducesBOM costs and casing size requirements. The metering design willalso benefit from immunity to magnetic tampering and enhancedreliability.A complete array of software development tools, demonstrationcode, and reference designs is available. These tools enable rapiddevelopment and certification of meters that meet all ANSI and IECelectricity metering standards worldwide.(Block diagrams on following pages)Benefits••Measurement accuracy meets even themost aggressive global standards––Exceeds the IEC 62053/ANSI C12.20standards––0.1% accuracy over 2000:1 current range––Meets Class 0.2 accuracy (71M6543H)••High integration and programmabilitymeet changing customer requirements––8-bit MPU (80515); up to 5 MIPS––Dedicated 32-bit CE––64KB flash and 5KB RAM(71M6541F/42F/43F/43H))––32KB flash and 5KB RAM (71M6541D)––Support up to 51 digital I/O pins(71M6542F/43F/43H)––LCD driver supports up to 336 pixels(71M6542F/43F/43H)––Two UARTs for IR and AMR––IR LED driver with modulation••Accelerate meter development––Complete array of in-circuit-emulation(ICE) and development tools––Flash programming and firmwaredevelopment tools––Programming libraries and referencedesigns––Third-party programming tools andsupport services••Improved reliability and cost savings––Using shunts instead of currenttransformers (CT) lowers BOM costs––Eliminate the cost of copper wire neededfor CTs––Using shunts allows smaller meterenclosure––Using shunts enables gain magnetic fieldimmunity*Future product—contact the factory for availability.www.maxim-ic.com/smartgrid 7

Smart metersFeatured productsEnergy-meter SoCs reduce cost while improving design flexibility and accuracy(continued)SHUNT CURRENT SENSORSCNEUTRALBLOADAPOWER SUPPLYNEUTRALNOTE:THIS SYSTEM IS REFERENCEDTO NEUTRAL71M6103*71M6103*71M6103*V 3P3A V 3P3SYS GNDA GNDD71M6543F*71M6543H*RESISTOR-DIVIDERSPULSETRANSFORMERSMUX AND ADCI N**V CI CV BI BV AIADC0IADC0 I ATEMPERATURESENSORRAMCOMPUTATIONENGINEPWR MODECONTROLWAKE-UPREGULATORV BATV BAT_RTCBATTERYMONITORRTCBATTERYBATTERYAMRIRHOSTV REFSERIAL PORTSTXRXRXMODULATOR TXPOWER-FAULTCOMPARATORSPIINTERFACEFLASHMEMORYMPURTCTIMERSICECOM0...5SEGSEG/DIOLCD DRIVERDIO, PULSESDIOV 3P3DOSC/PLLXINXOUTLCD DISPLAYPULSES,DIOI2C OR MICROWIRE ®EEPROM32kHz**I N = NEUTRAL CURRENTThe 71M6543F/71M6543H polyphase metering SoCs are ideal for commercial and industrial applications.(Block diagram on next page)*Future product—contact the factory for availability.8 Maxim Smart Grid Solutions

Smart metersFeatured productsEnergy-meter SoCs reduce cost while improving design flexibility and accuracy(continued)NEUTRALSHUNTLINESHUNTLOADNOTE:THIS SYSTEM IS REFERENCED TO LINENEUTRALLINEPOWER SUPPLY71M6601*V 3P3A V 3P3SYS GNDA GNDDLINERESISTOR-DIVIDERSPULSETRANSFORMERMUX AND ADCI API ANI BPI BNV AIADC0IADC071M6541D*71M6541F*TEMPERATURESENSORRAMCOMPUTATIONENGINEPWR MODECONTROLWAKE-UPREGULATORV BATV BAT_RTCBATTERYMONITORRTCBATTERYBATTERYAMRIRHOSTV REFSERIAL PORTSTXRXRXMODULATOR TXPOWER-FAULTCOMPARATORSPIINTERFACEFLASHMEMORYMPURTCTIMERSICECOM0...5SEGSEG/DIOLCD DRIVERDIO, PULSESDIOV 3P3DOSC/PLLXINXOUTLCD DISPLAYPULSES,DIOI2C OR MICROWIREEEPROM32kHzThe 71M6541D/71M6541F single-phase metering SoCs are ideal for residential and POL applications.*Future product—contact the factory for availability.www.maxim-ic.com/smartgrid 9

Smart metersFeatured productsHighly accurate MEMS RTC is less sensitive to shock and vibration thantraditional clocksDS3231MBenefitsThe DS3231M is a highly precise real-time clock (RTC) based on MEMSresonator technology. It meets the core requirements for accuracy,stability, power, and compliance testing for smart meters.This innovative RTC provides temperature-compensated timingaccuracy of ±0.5s/day (< ±5.0ppm) from -40°C to +85°C. The MEMStechnology makes the DS3231M less sensitive to shock and vibrationthan traditional crystal-based clocks. It is also less sensitive toaccuracy drift, which is quite common with aging quartz crystals.The DS3231M is a low-power device (< 3.0µA) that prolongs batterylife. Switching automatically between the main and battery power,it meets the industry requirement for dual-supply operation as asafeguard in the absence of main power.The DS3231M’s accuracy and stability make it particularly suitablefor multitariff metering. With no crystal to consume space and addcost, it is a low-cost solution for time-based billing and rate chargesdirectly at the meter. It is a viable option for metering networks thatdo not distribute time-of-day information between meters, but mustmaintain an accurate time base at the meter.••Meets the four core timing requirementsfor smart metering––Accuracy (< ±5.0ppm)––Stability (< ±5.0ppm)––Power (< 3.0μA)––Compliance testing (1Hz output)••Highly rugged, dependable solution––±5ppm lifetime accuracy––Optimized for high shock and vibration:> 20,000g––Requires no special handling duringultrasonic cleaning vs. quartz crystals••Safeguards against power loss––< 3.0μA power consumption extendsbattery life––Dual supply operation––Automatic switching between mainpower and battery power••Reduces cost and saves space––Miniature MEMS resonator eliminatesthe cost of a quartz crystal––No user calibration required, thusreducing cost––16- and 8-pin (150 mil) SO packages––Pin compatible with crystal-basedDS3231S RTCs32kHZDS3231MDIVIDERNV BATV CCRSTNPOWERCONTROLTIME-BASERESONATORTEMPSENSORDIGITALADJUSTMENT1HzINTERRUPTOR 1HzSELECTNINT/SQWGNDFACTORY TRIMSDASCLI 2 CINTERFACECONTROL AND STATUSREGISTERSCLOCK/CALENDARWITH ALARMBlock diagram of the DS3231M RTC.10 Maxim Smart Grid Solutions

Smart metersRecommended solutionsRecommended solutionsMetering SoCsPart Description Features Benefits71M6531/71M653271M6533/71M653471M6541D*/41F*/42F*Residential metering SoCs with an MPUcore, RTC, in-system programmable flash,and LCD driverPolyphase metering SoCs with 10MHz,8051-compatible MPU core; low-powerRTC; 128KB flash; and LCD driverHighly integrated single-phase meteringSoCsMultiple UARTs, I 2 C/MICROWIRE interface, and upto 30 DIO pins; support 2-, 3-, and 4-wire singlephaseand dual-phase residential metering; tamperdetectionmechanismsAdvanced power management with less than1µA sleep current; selectable single-ended ordifferential current sensing; large-format LCD driverExceed IEC 62053 and ANSI C12.20 standards;embedded isolated-sensing technology71M6543F*/43H* Highly integrated polyphase metering SoCs Exceed IEC 62053 and ANSI C12.20 standards;embedded isolated-sensing technologyReal-time clocks (RTCs)High integration and field programmabilityenable designers to adapt to changingcustomer requirements, speed time to market,and lower BOM costHigher sampling rate and larger code spaceoffer customers ability to extend metrologyfunctionality and implement advancedfunctions such as simultaneous broadband/narrowbandMeasurement accuracy meets even the mostaggressive global standards; offer flexibility inselecting interfaceSignificantly reduce BOM and enclosuresize by eliminating the need for currenttransformers in polyphase designsDS3231M Extremely accurate, MEMS-based, I²C RTC All-silicon MEMS resonator; requires no usercalibration; ±5ppm (±0.432s/day) timekeepingaccuracy over -40°C to +85°CDS3231DS3232DS3234Extremely accurate, I 2 C RTC with TCXO andcrystalExtremely accurate, I 2 C RTC with integratedcrystal and SRAMExtremely accurate, SPI RTC with integratedcrystal and SRAMBetter than ±2min/yr accuracy (< ±4ppm) over-40°C to +85°C; requires no user calibration±3.5ppm accuracy over -40°C to +85°C; 236 bytesof battery-backed SRAM±3.5ppm accuracy over -40°C to +85°C; 236 bytesof battery-backed SRAMReduces design time; minimizes piece-partcount in manufacturing lines; providesenhanced aging characteristics and lowersensitivity to shock and vibration; improveslong-term accuracySingle-chip timing solution improves accuracyand lowers design complexity over discretesolutions, which typically require a crystal,RTC, temperature sensor, and microprocessor,as well as user calibrationIntegrated memory allows storage of batterybackeddata, including billing information orconfiguration dataIntegrated memory allows storage of batterybackeddata, including billing information orconfiguration dataIsolated powerMAX5021/22High-performance current-mode PWMcontrollers for forward/flyback configurationUniversal power supply (85V to 265V); smallSOT23 package; integrated startup circuitSave board area; ideal for noise-sensitiveapplicationsMAX17499/500Current-mode PWM controllers withprogrammable switching frequencyIntegrated error amplifier regulates the tertiarywinding output voltage; input undervoltage lockout(UVLO)Eliminate the need for an optocoupler andensure proper operation during brownoutMAX5974/75Active-clamped, spread-spectrum, currentmodePWM controllersActive-clamp topology; regulation withoutoptocoupler; switching frequency is adjustable from100kHz to 600kHzAchieve > 90% efficiency, thus reducingpower consumption in synchronous forward/flyback power supplies; save space and costby eliminating the need for an optocoupler;optimize circuit magnetics and filter elementsto meet EMI requirements(Continued on next page)*Future product—contact the factory for availability.www.maxim-ic.com/smartgrid 11

Smart metersRecommended solutionsRecommended solutions (continued)DC-DC convertersPart Description Features BenefitsMAX1725/2612V, ultra-low-IQ, low-dropout linearregulators20mA output; 2µA quiescent current acrossoperating range and in dropout; reverse-batteryprotectionLow-power operation conserves battery lifeMAX15062*36V, 300mA DC-DC regulator withintegrated FETs in 2mm x 2mm TDFNLow quiescent current; internal compensation;synchronous operation; pulse-skip mode for lightloadsHigh integration with small footprint savesup to 50% total board area compared tocompeting solutionsTransformer driversMAX2563W, primary-side transformer H-bridgedriver for isolated suppliesProvides up to 3W to the transformer in isolatedpower suppliesSaves board area; reduces design complexity;makes it easy to implement isolated powerMAX2531W, primary-side transformer H-bridgedriver for isolated suppliesSpecifically designed to provide isolated power foran isolated RS-485 or RS-232 data interfaceSaves board area; reduces design complexity;makes it easy to implement isolated powerHall-effect sensorsMAX9639*/40* Low-power, single Hall-effect sensors Adjustable magnetic thresholds (MAX9639)simplify system design; ultra-low 2.6µA supplycurrentProvide simple open/close detection whilesaving powerSupervisorsMAX6854–69Supervisory circuits with manual reset andwatchdog timerUltra-low 170nA (typ) supply currentLow-power operation decreases drain onbatteryMAX16056–59Supervisory circuits with capacitoradjustablereset and watchdog timeoutsUltra-low 125nA (typ) supply currentLow-power operation decreases drain onbatteryVoltage referencesMAX6161–68Precision, micropower, low-dropout, highoutput-currentvoltage references in an8-pin SO package±2mV (max) initial accuracy; 5ppm/°C (max)temperature coefficientImprove system precision; reduce componentcount and board spaceFor a list of Maxim's recommended smart meter solutions, please go to: www.maxim-ic.com/smartmeter.*Future product—contact the factory for availability.12 Maxim Smart Grid Solutions

Power-grid monitoringOverviewPower-grid monitoringOverviewAdvanced power-grid monitoringsystems combine power-supplymonitoring, load-balancing, protection,and metering functions toenable safe and efficient powerdelivery. They also reduce operationand maintenance costs for utilities.These systems protect transformers,circuit breakers, and other equipmentat substations; they enable predictivemaintenance by detecting andresponding to fault conditions; theydynamically balance loads toconserve energy; and they monitorand control power quality. Theseadvanced capabilities are critical toensuring uninterrupted powerdelivery and supporting intelligentgrid-management applications.Accuracy requirementsThe rollout of advanced power-gridmonitoring systems is complicated bythe varying international standardsthat specify the accuracy requiredfor energy measurement. Real-timepower-delivery monitoring, faultdetection, fault protection, anddynamic load balancing requirestringent accuracy. As an example,the European Union IEC 62053standard for Class 0.2 equipmentrequires measurement precision tobe 0.2% of the nominal current andvoltage. For power-factor measurementaccuracy, sample-time phasematching should be 0.1% or better.Polyphase measurementsPower companies distribute threephase(polyphase) power using a“wye” connection. The term wyerefers to the arrangement of threetransformer windings that join ata common point, the junction ofthe Y. The line voltages are offsetin phase from each other by 120°,one-third of a cycle. If loads on eachof the three phases are equal, thesystem is balanced and no currentflows through the neutral line. Afourth, neutral, wire connects to thejunction of the wye. It accommodatesimbalanced loads across theline connections.Power-grid monitoring systems trackthe voltage and current on multiplephases with ADCs. The convertersmust be synchronized in order tomeet stringent standards requirementsand to accurately measurepower factor. In a typical scheme,each phase’s power parameters aremeasured with a current transformer(CT) and a voltage transformer (VT).The complete system comprises foursuch pairs: one pair for each of thethree phases, plus a neutral pair. TheADCs simultaneously measure thethree phases and neutral voltagesand currents. The active, reactive,apparent-energy, and power-factorparameters can be calculated fromthe sampled data, often by a DSP.International and local standardsalso dictate the necessary samplerate. These applications typicallyrequire accurate, simultaneous multichannelmeasurement over a widedynamic range of 90dB or better witha sample rate of 16ksps or higher.These capabilities enable analysis ofmultiple harmonics of the AC supplyPT/CTTRANSFORMERSOPAMPACTIVEFILTEROPTIONALVOLTAGEREFERENCEµPSUPERVISORTEMPSENSOROPTIONALMULTICHANNELADCRTC WITHNV RAMµCUARTTOCOMMUNICATIONSBLOCK(SEE pp. 25-40)OPAMPOPTIONALACTIVEFILTERDIGITALPOTENTIOMETEROPTIONALDACTOUCH-SCREENCONTROLLERPOWERMANAGEMENTOPTIONALMAXIMSOLUTIONBlock diagram of a typical power-grid monitoring system. For a list of Maxim's recommended power-grid monitoring solutions, please go to: www.maxim-ic.com/grid-monitoring.www.maxim-ic.com/smartgrid 13

Power-grid monitoringOverviewas well as detection of high-speedfault conditions, such as spikes andbrownouts.Analog-input signal chainDesigners of polyphase power-gridmonitoring systems are increasinglyrelying on precision, multichannelsimultaneous-sampling ADCs. TheseADCs simplify the sampling schemewhen compared to single ADCs thatrequire digital phase compensation.Simplifying the ADC design leads toreduced system cost, since all of thetiming among the ADCs is handledwithin the IC.The simultaneous-sampling ADCmust offer better than 90dB signalto-noiseratio (SNR) in order to meetthe dynamic range requirements formeasuring small voltage fluctuationson large AC signals. Maxim offerstwo simultaneous-sampling ADCfamilies that meet these requirements:the 24-bit MAX11040 with4 channels and 117dB SNR, andthe 16-bit MAX11044/MAX11045/MAX11046 with 4, 6, or 8 channelsand more than 92dB SNR.The transformers drive directly intothe ADC if the input impedance ofthe ADC is high enough; otherwise,a precision low-noise amplifier (LNA)is also needed. Maxim offers acomplete line of amplifiers with lessthan 10nV/√Hz noise and very lowoffsets. These amplifiers minimizemeasurement errors in the system toensure the highest possible accuracy.CommunicationsAside from the analog-input signalchain, power-grid monitoringsystems need specialized communicationscircuits to overcome thechallenges of transmitting andreceiving data in the harsh gridenvironment. Detailed informationabout power-grid communications isavailable on pages 25–40.Electronic calibrationAll practical components, bothmechanical and electronic, havemanufacturing tolerances. The morerelaxed the tolerance, the moreaffordable the component. Whencomponents are assembled into asystem, the individual tolerancessum to create a total system errortolerance. Through the properdesign of trim, adjustment, andcalibration circuits, it is possible tocorrect these system errors, therebymaking equipment more accurateand affordable.Digitally controlled calibration DACs(CDACs) and potentiometers (CDPots)provide quicker and simpler electroniccalibration than mechanical pots.They are also more reliable, andinsensitive to vibration and noise.Using these devices, manufacturerscan compensate for manufacturingtolerances during the final productiontest to meet target specifications.PHASE 1VTTRANSFORMERSECONDARYVTMAX11046CTTRANSFORMERSECONDARYCTADCADCNEUTRALADCLOADADCADCADCADCPHASE 2ADCPHASE 3An example of three-phase power monitoring in a wye configuration.14 Maxim Smart Grid Solutions

Power-grid monitoringOverviewAdditionally, electronic calibrationallows for periodic self-test and calibrationto compensate for environmentalfactors (e.g., temperature,humidity, and drift) in the field.CDACs and CDPots allow both thetop and bottom DAC voltage tobe set to arbitrary voltages, thusremoving excess adjustment range.In the calibration diagram below,a low value of 1V and a high valueof 2V are selected. To achieve a0.0039V step size over the 1V to 2Vrange, only an 8-bit device is needed.This approach reduces cost andincreases accuracy and reliability byremoving any possibility that thecircuit could be grossly misadjusted.The high and low voltages for theCDAC are arbitrary and, therefore,can be centered wherever circuitcalibration is required. Thus, thegranularity of the adjustmentcan be optimized for the specificapplication. In addition, CDACs andCDPots have internal nonvolatile(NV) memory, which automaticallyrestores the calibration settingduring power-up.Precision voltage referencesSensor and voltage measurementswith precision ADCs are only asgood as the voltage reference usedfor comparison. Likewise, outputcontrol signals are only as accurateas the reference voltage supplied tothe DAC, amplifier, or cable driver.Common power supplies are notadequate to act as precision voltagereferences. They are not accurateenough and drift far too much withtemperature.Compact, low-power, low-noise, andlow-temperature-coefficient voltagereferences are affordable and easyto use. In addition, some referenceshave internal temperature sensors toaid in the tracking of environmentalvariations.ORDINARY DAC4VREFIN4V10-BITDACOUT10 BITS, 1024 STEPSGroundFB0.0039Vper stepGROUNDCALIBRATION DAC2V2VREFHI8-BITDAC8 BITS, 256 STEPS1VREFLOOUT1VComparing the calibration range of an ordinary DAC to a CDAC.www.maxim-ic.com/smartgrid 15

Power-grid monitoringFeatured productsADC’s high-impedance input eliminates external components and reduces system costMAX11046BenefitsThe MAX11046 is the industry’s first true 16-bit, 8-channel simultaneoussamplingSAR ADC. The device’s proprietary architecture provides anultra-low-noise, on-chip, negative supply voltage. This innovativetechnology achieves true 16-bit performance from a high-impedancebipolar input using only a single positive external supply. Performanceexceeds the regulatory requirements for Class 0.2 precision (0.2% of220V) mandated by IEC 62053.The high-impedance input allows a lowpass filter prior to the ADCinputs, thus eliminating the need for precision external buffers. Thebipolar input eliminates a level shifter. Simultaneous sampling easesthe typical requirement for phase-adjust firmware and thus speedsend designs and time to market. Together, these benefits simplifythe design challenges for power-grid monitoring and measurementequipment. This ADC performance is unprecedented, and designswill save cost, area, and power.••Saves up to $1/channel*––High-impedance input eliminatesexternal buffers for precision designs––Bipolar input eliminates a level shifter––5V single-supply operation––Integrated 20mA surge protection••Provides the highest precision––Industry-leading SNR and THD––True 16-bit performance exceeds theEN 50160 and IEC 62053 requirementsfor Class 0.2 power-grid equipment••Simplifies design and shortens time tomarket––Simultaneous sampling simplifies phaseadjustfirmware requirementsMAX11046CH0CH7CLAMPCLAMPT/HT/H16-BIT ADC16-BIT ADCDATA REGISTERSBIDIRECTIONAL DRIVERSDB15DB4DB3DB0CONFIGURATIONREGISTERSINTERFACEANDCONTROLWRRDCSCONVSTEOCBlock diagram of the MAX11046 16-bit, 8-channel, simultaneoussamplingADC. Eight inputs measure voltage and current signals onthree phases plus neutral.*Cost savings achieved by eliminating external amplifiers and level-shifting circuitry.16 Maxim Smart Grid Solutions

Power-grid monitoringFeatured productsADC simplifies firmware by capturing accurate phase and magnitudeinformation on up to 32 channelsMAX11040BenefitsThe MAX11040 sigma-delta ADC offers 117dB SNR, four differentialchannels, and simultaneous sampling that is expandable to 32channels (i.e., with eight MAX11040 ADCs in parallel). Witha programmable phase and sampling rate, the MAX11040 isideal for high-precision, phase-critical measurements in a noisypower-monitoring environment. Using a single command, the ADC’sSPI-compatible serial interface allows data to be read from all thecascaded devices. Four modulators simultaneously convert each fullydifferential analog input with a 0.25ksps to 64ksps programmabledata-output rate. The device achieves 106dB SNR at 16ksps and117dB SNR at 1ksps.••Simplifies digital interface to amicrocontroller––Eight MAX11040 ADCs can be daisychained through the SPI interface••Easily measures a wide dynamic range––117dB SNR at 1ksps allows users tomeasure both very small and large inputvoltages••Easily measures the phase relationshipbetween multiple input channels––Simultaneous sampling preservesphase integrity between current andvoltage transformers in a polyphaseenvironmentµCSingle SPI CSAVDDDVDD4-channel,fully differentialbipolar inputsAIN0+AIN0-REF0AIN1+AIN1-REF1AIN2+AIN2-REF2AIN3+AIN3-REF3REFAGNDADCADCADCADC2.5VXTALOSCILLATORXINXOUTDIGITAL FILTERDIGITAL FILTERDIGITAL FILTERDIGITAL FILTERMAX11040SPI/DSPSERIALINTERFACESAMPLINGPHASE/FREQADJUSTMENTDGNDN = 1SYNCCASCINCASCOUTSPI/DSPCSSCLKDINDOUTINTN = 2Fine/coarsesample-rateand phaseadjustmentN = 8The MAX11040 can be cascaded up to 32 simultaneous channels.www.maxim-ic.com/smartgrid 17

Power-grid monitoringFeatured productsMicroprocessor supervisor delivers high accuracy and reliability with reduced total costMAX16055To improve system reliability, you should monitor all the voltagerails for undervoltage conditions. Instead of using separate discretevoltage supervisors that consume valuable board space, you can usea MAX16055 ultra-small microprocessor supervisor. This device integratessix channels of undervoltage monitoring into a space-savingµMAX® package. The MAX16055 thus significantly reduces systemsize and component count while improving reliability compared tomultiple ICs or discrete supervisors.The MAX16055 also includes a manual-reset input and a toleranceselectinput for choosing between 5% and 10% threshold tolerances.The manual-reset feature is especially versatile and practical. Use itto force a reset even when all the voltage rails are within tolerance. Itcan also cascade multiple voltage monitors or connect to a separatewatchdog timer.Benefits••High integration saves board space––Six-channel voltage monitor is availablein a tiny 3mm x 3mm µMAX package••Highly adjustable to accommodatechanging design requirements––Fixed and adjustable voltage thresholds;adjustable threshold monitors down to0.5V with ±1.5% accuracy––Manual-reset and tolerance-select inputs––Fully specified to +125°CThe MAX16055 single-chip solution offers up to nine differentcombinations of fixed-voltage thresholds and resistor-adjustablethresholds. It is fully specified up to +125°C.IN1MAX16055IN2MRIN3IN4RESETTIMEOUTRESETIN5IN6TOL0.5VREFERENCEGNDBlock diagram of the MAX16055 6-voltage microprocessor supervisor.18 Maxim Smart Grid Solutions

Power-grid monitoringFeatured productsSimple reset and monitoring circuits enable easy sequencing and flexible monitoringMAX16052/MAX16053BenefitsThe MAX16052/MAX16053 are low-power, high-voltage monitoringcircuits with sequencing capability. Each device monitors a voltagerail with a threshold set by an external resistor. Using this externallyadjustable threshold, the MAX16052/MAX16053 monitor a widevariety of power-supply voltages. A single output with a capacitorprogrammabledelay can be used to adjust the sequencing delaybetween power-supply rails.The MAX16052/MAX16053 are ideal for use in power-supply sequencing,reset sequencing, and power-switching applications. The deviceswork especially well for sequencing the multiple power suppliesrequired by high-performance DSPs and other complex ICs. In atypical application a MAX16052/MAX16053 is powered from a 12Vsupply rail and monitors a power supply that is derived from themain 12V rail, while turning on a second power-supply rail after aprogrammable time delay.••Save cost while offering highestflexibility––Operate over 2.25V to 16V to supporthigh-voltage applications––Can be powered up directly from theintermediate bus––Use the external resistor/capacitor tomonitor a wide range of power-supplyvoltages and programmable timingdelays12VDC-DC3.3VDC-DC1.8VDC-DC0.9VPowered directly fromintermediate busENABLEENABLE V CCINMAX16052OUTENABLEENABLE V CCINMAX16052OUTENABLE28V-tolerantopen-drainoutputResistorsset tripthresholdsGNDCDELAYGNDCDELAYCapacitor setstiming delayThe MAX16052 in a typical monitoring application.www.maxim-ic.com/smartgrid 19

Power-grid monitoringFeatured productsDigital potentiometers automate calibration of line-monitoring instrumentsMAX5422/MAX5423/MAX5424The MAX5422/MAX5423/MAX5424 nonvolatile, linear-taper digitalpotentiometers perform the function of a mechanical potentiometer,but replace the mechanics with an integrated resistor stringcontrolled with a simple 3-wire, SPI-compatible digital interface.This design minimizes board space and reduces interconnectioncomplexity in many applications. Each device performs the samefunction as a discrete potentiometer or variable resistor and has256 tap points.Benefits••Optimize board layout––Tiny 3mm x 3mm TDFN package••Retain calibration even during powercycling––Nonvolatile memory restores the wiperposition during power-upThese digital potentiometers feature internal nonvolatile (NV) EEPROMused to store the wiper position for initialization during power-up. Thisenables the devices to be used in “dumb” applications where there isno host processor. The 3-wire SPI-compatible serial interface allowscommunication at data rates up to 5MHz. The devices provide threenominal resistance values: 50kΩ (MAX5422), 100kΩ (MAX5423), or200kΩ (MAX5424). The nominal resistor temperature coefficient is35ppm/°C end-to-end and only 5ppm/°C ratiometric.HV DDGND8-BITSHIFTREGISTER8 256-8-BIT8 256POSITIONLATCHDECODERWLCSSCLKDINSPIINTERFACEPOR8-BITNVMEMORYMAX5422MAX5423MAX5424Block diagram of the MAX5422/MAX5423/MAX5424.20 Maxim Smart Grid Solutions

Power-grid monitoringFeatured productsCalibration voltage references with temperature sensor increase system precisionMAX6173–MAX6177BenefitsThe MAX6173–MAX6177 are low-noise, high-precision voltagereferences. The devices feature a proprietary temperaturecoefficient,curvature-correction circuit and laser-trimmed thin-filmresistors that result in a very low 3ppm/°C temperature coefficientand excellent ±0.06% initial accuracy. A trim input allows finetrimming of the output voltage with a resistive-divider network.Low temperature drift and low noise make the devices ideal for usewith high-resolution ADCs or DACs. The MAX6173–MAX6177 acceptinput voltages up to 40V. The devices draw 320µA (typ) of supplycurrent and source 30mA or sink 2mA of load current. They operateover the -40°C to +125°C automotive temperature range.••Optimize system error budget––±0.06% (max) initial accuracy––±3ppm/°C (max) temperature stability••Save cost and valuable board area––Short-circuit protection––No external capacitors required forstability( V OUT + 2V) TO 40V INPUTINOUTREFERENCEOUTPUT*MAX6173-MAX6177TEMPTRIMMAX543650kΩPOTENTIOMETERGND*OPTIONALBlock diagram of the MAX6173-MAX6177 precision voltage references.www.maxim-ic.com/smartgrid 21

Power-grid monitoringRecommended solutionsRecommended solutionsPart Description Features BenefitsPrecision analog-to-digital converters (ADCs)MAX1104024-bit, 4-channel, simultaneoussamplingdelta-sigma ADC64ksps; internal reference; cascade to capture phaseand magnitude on up to 32 channels; 117dB SNRMinimal firmware complexity speeds time tomarketMAX11044/45/4616-bit, 4-/6-/8-channel,simultaneous-sampling SAR ADCs3μs conversion time; 250ksps for all eight channels;92dB SNR; -105dB THD> 1MΩ input impedance eliminates externalbuffers, saving space and up to $1/channel**MAX11054*/55*/56*14-bit, 4-/6-/8-channel,simultaneous-sampling SAR ADCs3μs conversion time; 250ksps for all eight channels14-bit, pin-compatible versions of theMAX11044/45/46 make it simple to trade offresolution vs. costMAX1324/25/2614-bit, 2-/4-/8-channel,simultaneous-sampling SAR ADCs3.7μs conversion time; 250ksps for all eightchannels; 77dB SNR; -86dB THDPin-compatible packages make it simple todesign 2, 4, or 8 channels; flexibility with 0 to5V, ±5V, or ±10V input rangesPrecision operational amplifiersMAX9618/19/20 Ultra-low-power, zero-drift op amps Continuous self-calibration at any voltage ortemperatureSave maintenance system downtime andmaintain system accuraciesMAX9613/15 Low-power, autotrim op amps Self-calibration feature on startup Save maintenance system downtime andmaintain system accuraciesMAX9943/44 38V, low-noise, precision op amps Excellent combination of low power (550µA) andprecision (V OS of 100µV)MAX9945 38V, CMOS-input, single op amp Excellent precision with 50fA low-input-biascharacteristicsActive filtersHigh-voltage precision conditioning without highpower dissipation minimizes temperature errorsHigh-voltage CMOS inputs with very low biascurrent allow signal conditioning of high-ohmicsensorsMAX7409/10/13/145th-order, switched-capacitorlowpass filtersClock- or capacitor-adjustable corner frequency to15kHz; 1.2mA supply currentSave space and cost by replacing discretedesignsMAX7422–255th-order, switched-capacitorlowpass filtersClock- or capacitor-adjustable corner frequency to45kHz; 3mA supply currentSave space and cost by replacing discretedesignsMAX274/758th-order/4th-order, 150kHz/300kHz,lowpass/bandpass filtersResistor programmable; continuous-time filters; lownoise (-89dB THD)Save space and cost by replacing discretedesignsCalibration digital potentiometers (CDPots)MAX54811024-tap (10-bit) CDPot with SPI orup/down interface1.0µA (max) in standby; 400µA (max) duringmemory write1024 taps provide very accurate calibrationMAX5477Dual, 256-step (8-bit) CDPot with I 2 CinterfaceEEPROM write protection; single-supply (2.7V to5.25V) operationEEPROM protection retains calibration data sono host processor is requiredMAX5427/28/29Low-cost, one-time-programmable(OTP) digital potentiometers withup/down interface1µA (max) standby current (no programming);35ppm/°C end-to-end and 5ppm/°C ratiometrictempcoIncrease power savings and improvemeasurement accuracy over temperaturechangesMAX5494–9910-bit, dual, nonvolatile voltagedividersor variable resistors withSPI interface function as digitalpotentiometers1µA (max) standby current (no programming);35ppm/°C end-to-end and 5ppm/°C ratiometrictempcoImprove power savings and improvemeasurement accuracy over temperaturevariationsMAX5422Single, 256-step (8-bit) CDPot withSPI interfaceTiny 3mm x 3mm TDFN packageReduces board space(Continued on next page)*Future product—contact the factory for availability.**Cost savings achieved by eliminating external amplifiers and level-shifting circuitry.22 Maxim Smart Grid Solutions

Power-grid monitoringRecommended solutionsRecommended solutions (continued)Part Description Features BenefitsCalibration digital-to-analog converters (CDACs)MAX5134–37,MAX5138/391-/2-/4-channel, 16-/12-bit DACswith pin-programmable zero ormidscale power-upOutput set to zero or midscale upon power-upAdd extra safety during power-upMAX5661Single-channel DAC with 16-bitvoltage- or current-buffered outputIntegrated high-voltage current and voltageamplifiers; serial interfaceReduces external component count; reducescostMAX55004-channel, 12-bit DAC with precisionamplifier-output conditionersOutput conditioners; 0.85mA quiescent current (I Q )Needs no external amplifiers; makes equipmentmore cost effectiveMAX5105/15Quad, 8-bit CDACs with independenthigh- and low-reference inputsRail-to-rail output buffers; choice of I 2 C or SPIinterfaceSelectable voltage range improves granularityand prevents unsafe adjustmentsMAX5106Quad, 8-bit CDAC with independentlyadjustable voltage rangesAllows customization of calibration granularity; small5mm x 6mm packageAvoids grossly misadjusted system at the startof the calibration procedure; reduces cost ofthe calibration DAC by reducing the requiredresolutionTouch-screen controllersMAX11800 Resistive touch-screen controller FIFO; spatial filtering; SPI interface Simplifies the task of identifying touch eventsMAX11801 Resistive touch-screen controller FIFO; spatial filtering; I 2 C interface Simplifies the task of identifying touch eventsMAX11802Resistive touch-screen controller withSPI interfaceSPI interfaceBasic feature set for lowest costMAX11803Resistive touch-screen controller withI 2 C interfaceI 2 C interfaceBasic feature set for lowest costMAX11811Resistive touch-screen controller withhaptics driverIntegrated haptics driver; I 2 C interfaceAdds tactile feedback to resistive touch screensfor improved usabilityUARTMAX3107SPI/I 2 C UART with integratedoscillator24Mbps (max) data rates; power-save features;RS-485 control; four GPIOs; 24-pin SSOP or smallTQFN (3.5mm x 3.5mm) packagesTiny package saves board space;high integration of features frees upmicrocontrollerVoltage references, calibration voltage references (CRefs), and E²CRefsMAX6173Precise voltage reference withtemperature sensor±0.05% (max) initial accuracy; ±3ppm/°C (max)temperature stabilityAllows analog system gain trim whilemaintaining the digital accuracy of ADCsand DACs; allows easy system temperaturecompensationMAX6220DS4303Low-noise, precision voltagereferenceElectronically programmable voltagereference (E²CRef)8V to 40V input-voltage range; ultra-low 1.5µV P-Pnoise (0.1Hz to 10Hz)Wide, adjustable output-voltage range can be setwithin 300mV of the supply rails with ±1mV accuracyEnables dependable operation during brownoutAutomates production test through easycalibration for reference voltages from 0.3V to2.7V(Continued on next page)www.maxim-ic.com/smartgrid 23

Power-grid monitoringRecommended solutionsRecommended solutions (continued)Voltage supervisorsPart Description Features BenefitsMAX16052/53MAX6746–53MAX6715–29,MAX6730–35MAX16000–07,MAX16008/09High-voltage, adjustable sequencing/supervisory ICsCapacitor-adjustable watchdog timerand reset ICs1-/2-/3-voltage µP supervisorycircuits with independent watchdogoutputLow-voltage, 4-/6-/8-voltage µPsupervisors in TQFN package2.25V to 16V supply range; adjustable voltagethresholds and reset timeoutCapacitor-adjustable timing; 3μA supply currentMultiple fixed and one adjustable thresholds±1.5% accuracy; integrated watchdog timer; manualresetand margin-disable inputsMAX16055 Ultra-small, 6-voltage µP supervisor Low 35µA supply current; fully specified up to+125°CHigh-voltage input reduces costs; adjustablevoltage thresholds increase flexibilityVersatile for easy design reuse; save space insmall modulesA single multivoltage IC increases reliability andsaves board space by replacing multiple devicesImprove reliability; simplify design and lower theoverall system cost; reduce board spaceIncreases reliability; saves power; reduces totalsolution size and costPower suppliesMAX15023/26Low-cost, small, DC-DCsynchronous buck controllers (dual/single)Versatile operation from 4.5V to 28V; suitable formultiple applicationsSave space and costMAX1504640V, high-performance, synchronousbuck controller4.5V to 40V input-voltage range; adjustable outputsfrom (0.85 x V IN ) down to 0.6V; 100kHz to 1MHzswitching frequencyVersatile for easy design reuse; saves space insmall modulesReal-time clocks (RTCs) with NV RAMDS1747 RTC with 512k x 8 NV SRAM Integrated NV SRAM, RTC, crystal, power-fail controlcircuit, lithium energy sourceDS17285/87,DS17485/87,DS17885/87Temperature sensors3V/5V RTCsRTC/calendar; one time-of-day alarm; threemaskable interrupts with a common interrupt output;programmable square wave; 2KB to 8KB of batterybackedNV SRAMSaves space and cost by integrating NV memoryand RTC; retains data during power outageSave space and cost by integrating memory andRTC; retain clock data during power outageDS7505Low-voltage digital thermometer andthermostat±0.5°C accuracy from 0°C to +70°C; 1.7V to 3.7Voperation; industry-standard pinoutDS18B20 1-Wire ® digital temperature sensor ±0.5°C accuracy; 1-Wire interface; 64-bit laseredID codeMAX6603 Dual-channel platinum RTD interface Two input channels for PT200 RTDs; analog outputs;±5kV ESD protectionFor a list of Maxim's recommended power-grid monitoring solutions, please go to: www.maxim-ic.com/grid-monitoring.Industry-standard pinout allows easy accuracyupgrade and supply-voltage reduction fromLM751-Wire interface and 64-bit ID code allowmultiple distributed precision sensors on asingle busSaves space and cost24 Maxim Smart Grid Solutions

CommunicationsOverviewCommunicationsOverviewAn electricity grid without adequatecommunications is simply a power“broadcaster.” It is through theaddition of two-way communicationsthat the power grid is made “smart.”Communications enables utilities toachieve three key objectives: intelligentmonitoring, security, and loadbalancing. Using two-way communications,data can be collected fromsensors and meters located throughoutthe grid and transmitted directlyto the grid operator’s control room.This added communications capabilityprovides enough bandwidth forthe control room operator to activelymanage the grid.The communications must bereliable, secure, and low cost.The sheer scale of the electricalgrid network makes cost a criticalconsideration when implementinga communications technology.Selecting a solution that minimizesthe number of modems and concentratorsneeded to cover the entiresystem can dramatically reduce infrastructurecosts. At the same time,the selected technology must haveenough bandwidth to handle all datatraffic being sent in both directionsover the grid network.Communications networksand protocolsCommunications in the smart gridcan be broken into three segments.Wide area network (WAN) coverslong-haul distances from thecommand center to local neighborhoodsdownstream.Neighborhood area network (NAN)manages all information betweenthe WAN and the home area networkusing medium-voltage lines.Home area network (HAN) extendscommunication to endpoints withinthe end-user home or business.Each segment is interconnectedthrough a node or gateway: aconcentrator between the WAN andNAN and an e-meter between theNAN and HAN. Each of these nodescommunicates through the networkwith adjacent nodes. The concentratoraggregates the data from themeters and sends that informationto the grid operator. The e-metercollects the power-usage data of thehome or business by communicatingwith the home network gateway orfunctioning as the gateway itself.Each segment can utilize differentcommunications technologies andprotocols depending on the transmissionenvironments and amountof data being transmitted. In additionto the architecture choice betweenwireless and powerline communications(PLC), there are a variety ofwireless and PLC protocols to chooseamong (Table 1).AC LINEPOWERLINECOMMUNICATIONSINBOUNDOUTBOUNDPOWERLINECOMMUNICATIONSAC LINEMODEMMODEMDC-DCDC-DCSERIALMULTIPROTOCOLRS-232 RS-485OTHERMETERSTRANSFORMER DRIVERWIRELESSCOMPLETE RF TRANSCEIVERCOMPLETE RF TRANSCEIVERWIRELESSADCADCANTENNADC-DCSWPALNADRIVERUP-CONVERTERDOWN-CONVERTERUP-CONVERTERADCDACDACMAXIMSOLUTIONADCDACDACDOWN-CONVERTERLNADRIVERPASWDC-DCANTENNAMaxim offers solutions for powerline, wireless, and serial communications. For a list of Maxim's recommended solutions, please go to: www.maxim-ic.com/communications.www.maxim-ic.com/smartgrid 25

CommunicationsOverviewTable 1: Smart grid communications protocolsNetwork Protocol Advantages Disadvantages RecommendationWANWireless (2G/3G/LTEcellular, GPRS)Extensive cellular infrastructure is readilyavailable; large amount of aggregated datacan be communicated over a long haulUtility must rent the infrastructure from acellular carrier for a monthly access fee; utilitydoes not own infrastructureNAN Wireless ISM Long range; leaps transformers Currently proprietary; dead spots complicateinstallation and maintenanceWireless usually works bestUseful in some topologies, such as in theU.S.IEEE ® 802.15.4g Long range; leaps transformers Not yet an accepted standard Useful in some topologiesZigBee ®First-generation PLC(FSK, Yitran, Echelon ® )Early-generationnarrowband OFDMLow cost; low power consumption allowsbattery operation; well-known standardLow data rate; very short range; does notpenetrate structures wellUnlikely to be used in NANsLow cost Unreliable; low bandwidth Bandwidth and reliability inadequate forthe smart gridBetter range, bandwidth, and reliabilitythan FSKDoes not cross transformers; does not coexistwith first-generation PLCNot recommended for new designs due tocost and compatibility concernsBroadband PLC High data rate Does not cross transformers Increases infrastructure cost, making it toocostly for most large-scale deploymentsG3-PLCHighly reliable long-range transmission;crosses transformers, reducinginfrastructure costs; data rate supportsfrequent two-way communications;coexists with FSK; open standard;supports IPv6HAN ZigBee Well-known standard that offers low costand low powerNot yet an accepted standardVery short range; does not penetratestructures wellWi-Fi ® Popular technology with high data rates Medium range; does not penetrate cementbuildings or basementsFirst-generation PLC(FSK, Yitran, Echelon)Early-generationnarrowband OFDMExcellent for NAN worldwideWell suited for communication betweenwater and gas metersGood for consumer applications, but noprovisions for meeting utility objectivesLow cost Not reliable in home environments Unlikely to be used in homes due to highlevels of interferenceBetter range, bandwidth, and reliabilitythan FSKDoes not cross transformers; does not coexistwith first-generation PLCNot recommended for new designs due tocost and compatibility concernsBroadband PLC High bandwidth Short range is not sufficient for NAN Good for consumer applications, but noprovisions for meeting utility objectivesG3-PLCHighly reliable; sufficient data rate; IPv6enables networking with many devicesNot yet an accepted standardExcellent for HAN worldwideThe WAN is the communications pathbetween the grid operator and theconcentrator. The WAN can be implementedover fiber or wireless mediausing Ethernet or cellular protocols,respectively. Cellular or WiMAX® ismost commonly used between thegrid operator and the concentrator.The NAN is the path between theconcentrator and the meter. It useseither wireless or PLC. Typically, theconcentrator communicates withanywhere from a few to hundredsof meters, depending on the gridtopology and the communicationsprotocol used. Today, thereis no standard for this portion ofthe network, so most implementationsuse proprietary wireless orPLC technologies. Several standardsbodies are currently working withutilities and technology providersto define standards for wirelessand PLC protocols. The IEEE802.15.4g standard targets wireless;the IEEE P1901, OPEN meter, andITU-T G.hnem standards are beingdeveloped for PLC (Table 2).The HAN is used by utilities to extendthe reach of their communicationpath to devices inside the home.This network can support functionssuch as cycling air conditioners offduring peak load conditions, sharingconsumption data with in-homedisplays, or enabling a card-activatedprepayment scheme. The arrivalof electric/plug-in hybrid electricvehicles (EV/PHEVs) presents a specialcommunications scenario for HANs.Standards bodies are defining PLCprotocols for communicating withvehicle charging systems.In addition to supporting the datarequirements for smart grid activities,a HAN might also include: peer-topeer(P2P) communications betweendevices inside the home; communicationswith handheld remote-controldevices, lighting controls, and gas orwater meters; as well as broadband26 Maxim Smart Grid Solutions

CommunicationsOverviewOUTSIDE THE WALLINSIDE THE WALLWANNANHANNETWORKOPERATINGCENTERSMART GRIDNETWORKSMART HOMENETWORKMANAGEMENTSYSTEMSRELAY00000ELECTRICITYMETER00000WANEthernetCDMAGSMCONCENTRATORCAP BANK/E-BRIDGE0000000000SWITCH/S-BRIDGEGASMETER000000000000000000000The smart grid communications architecture.Table 2: Communication protocols under consideration around the worldRegion WAN NAN HANNorth America Cellular, WiMAX G3-PLC, HomePlug ® , IEEE 802.15.4g, IEEE P1901,ITU-T G.hnem, proprietary wireless, Wi-FiG3-PLC, HomePlug, ITU-T G.hn, Wi-Fi, ZigBee, Z-WaveEurope Cellular G3-PLC, IEEE P1901, ITU-T G.hnem, PRIME, Wi-Fi G3-PLC, HomePlug, ITU-T G.hn, Wi-Fi, Wireless M-Bus,ZigBeeChinaCellular, band-translatedWiMAXG3-PLC, RS-485, wireless to be determinedG3-PLC, RS-485, Wi-Fi, to be determinedRest of the World Cellular, WiMAX G3-PLC, HomePlug, IEEE 802.15.4g, IEEE P1901,ITU-T G.hnem, PRIME, RS-485, Wi-FiG3-PLC, HomePlug, ITU-T G.hn, RS-485, Wi-Fi, WirelessM-Bus, ZigBee, Z-Wavewww.maxim-ic.com/smartgrid 27

CommunicationsOverviewtraffic. Protocols such as RS-485,ZigBee, Z-Wave®, and HomePlugare used for this network. If there is aseparate home gateway, it is possiblethat additional protocols could beused to communicate with appliances,thermostats, and other devices.Communications alternatives in theHAN can often coexist, but utilitysupport will probably be limited totechnologies needed to supportthe utility's primary objectives.RF communicationsWireless communications is usedin some areas for automated meterreading (AMR). Several proprietary andstandardized wireless protocols areavailable today. Frequency bands ofinterest range from 200MHz to 3.9GHz.Several blocks are used to implementRF communications (Figure 3). Thesignal is received through an antennaand goes through a bandpass filter,which rejects frequencies beyondthe one of interest. The signal is thenswitched to the receive signal chain,where one or more downconverterstranslate from the carrier frequency toan intermediate frequency (IF), thento the in-phase/quadrature-phase(I/Q) stage, and then to the baseband.More recent architectures eliminateone or more of the IF downconversionstages with a low-IF or zero-IFsampling architecture. These designsuse either a single ADC to digitizea high- or low-IF signal or, typically,two ADCs to digitize a complex I/Qbaseband signal. The ADC outputis fed into a DSP or digital ASICwhere the baseband is processed.Sometimes a microprocessor is alsoused to handle the higher layers ofthe protocol. For transmission, theprocessing path and signal chain arereversed, and the signal is sent out tothe antenna.The system can be partitioned inseveral ways. ZigBee or Maxim’sSimplelink radios, for instance, canprovide a complete system-on-chip(SoC) solution. In other cases, such asproprietary protocols, a digital ASICand an RF transceiver are used tobuild the complete radio link. Maximhas both standard RF transceiversas well as custom ASICs that can beconfigured as transceivers.Powerline communicationsOverview of modulation schemesPowerline communications usesAC power lines as the transmissionmedium. Some systems, such asMaxim’s, work over DC and cold wiresas well. There are several powerlineprotocols in the market today. Theseprotocols break down into one oftwo basic modulation schemes:frequency-shift keying (FSK) andorthogonal frequency-division multiplexing(OFDM).FSK is an older modulation schemethat has been used by the utilityindustry in the past for rudimentarypurposes, such as infrequentone-way communications frommeters to a concentrator. However,FSK suffers from a significantdrawback: if an interferer coincideswith one of the transmit frequencies,the receiver loses reception.As FSK only switches between twofrequencies, bandwidth is not usedefficiently, resulting in low data rates.This low data rate is insufficient forsmart grid applications that demandbidirectional control.Real-world PLC rollouts frequentlyrequire up to several hundredmeters to be connected to a singledata concentrator over the mediumvoltage(MV) portion of the network.This requires data communicationacross low-voltage/medium-voltage(LV/MV) transformers. Since thesetransformers can cause several tens ofdecibels of (frequency-selective) signalattenuation to FSK signals, moreadvanced and robust communicationmethods than FSK are needed.OFDM has been used in manymodern communication systemssuch as digital radio and TV, Wi-Fi,and WiMAX, as well as early-generationnarrowband protocols such asPRIME. Today, OFDM technology isenabling exciting new functions andcapabilities for PLC networks. Amongthe most significant benefits, it givesthe utility industry the bandwidthneeded to build intelligence into thepower grid while meeting aggressivecost targets.Advancements offered byG3-PLC technologyG3-PLC employs OFDM to optimizebandwidth utilization. Since OFDMuses multiple carriers to transmit data,interference at a specific frequencyor frequency-selective attenuationcan now effectively be eliminated. Inaddition to increased reliability, thiscapability allows considerably moredata to be sent.Additionally, OFDM’s spectral efficiencyallows the use of advancedchannel-coding techniques. InMaxim’s powerline solutions,advanced channel coding is usedalong with OFDM to maximizecommunication robustness inadverse channel conditions. Twolayers of error-correction coding(convolutional and Reed Solomon)are used to ensure reliable datatransmission. In addition, datais interleaved in both time andfrequency domains across OFDMcarriers to decrease the sensitivity toimpulse noise and protect againstburst errors.Maxim’s next-generation G3-PLCtechnology includes additionalcapabilities:• MAC-level security using anAES-128 cryptographic engine• Mesh routing protocol todetermine the best path betweenremote network nodes28 Maxim Smart Grid Solutions

CommunicationsOverview• Adaptive tone mapping foroptimal bandwidth utilization• A robust mode of operation toimprove communication undernoisy channel conditions• Channel estimation to selectthe optimal modulation schemebetween neighboring nodes• Coexistence with older S-FSKsystemsG3-PLC is so robust that transmissionacross transformers is achievablewith an inexpensive coupler. Thisreduces the number of concentratorsneeded in smart grid installations,saving system implementation costand making PLC cost competitivewith, or even superior to, wirelessadvanced meter infrastructure (AMI)systems. Distances up to 6km havebeen achieved on low- and mediumvoltagelines, allowing remote sites tobe monitored as well. The completeG3-PLC profile specification, as wellas specifications for the PHY and MAClayers, can be downloaded from:www.maxim-ic.com/G3-PLC.Maxim provides both highfrequencyand low-frequency PLCchipsets for smart grid applications.Maxim recommends using narrowbandOFDM to transmit data in aspectrum consistent with worldwidespectral power-densitystandards for PLC (below ~500kHzin CENELEC®, FCC, and ARIB).Serial communicationsAchieve long cable runs in noisyenvironmentsIn harsh and noisy environments,such as multi-unit residentialbuildings or industrial settings, anRS-485 bus architecture can be usedto implement a low-cost, yet robustcommunications network. The differentialnature of RS-485 signalingmakes it less susceptible to externalinterference. Moreover, the RS-485specification supports multidropconfigurations, thus allowing theconnection of multiple meters to asingle bus.For instance, RS-485 can be used inan apartment building to transmitdata from meters in each apartmentto a central unit that aggregates thedata from the individual meters,which can then be read througha wireless or PLC link. A similarapproach can be used in industrialsystems that require multiple costcenters to be metered.Selecting an RS-485 transceiverTo maintain signal quality over longcable lengths through noisy environments,designers should lookfor transceivers with the followingfeatures.ESD protection to prevent damagefrom handling and connection of thetransceivers.Fail-safe circuitry to protect thedesign from open- and short-circuitconditions.Slew-rate limiting to reduceradiated emissions and data errors.Hot-swap capability to eliminatefalse transitions on the bus duringpower-up or live insertion of thetransceiver.Isolation to protect against voltagespikes, ground loops, electricalstorms, etc.AutoDirection control to save anoptocoupler by eliminating the needfor an isolated control channel.±80V fault protection to eliminatethe need for external componentssuch as polyswitch limiters and zenerdiodes.Add a point-to-point link withRS-232 transceiversThe RS-232 protocol is intendedfor short-distance communicationbetween two devices. Meterdesigners typically use RS-232 forimplementing a point-to-pointlink between a utility meter and acomputer, remote display, or modem.Because the RS-232 port is onlyused a fraction of the time, it shouldinclude automatic shutdown circuitryto conserve power. Additionally,designers should look for deviceswith extended ESD protection toprevent damage during handling.Maxim’s RS-232 family combinesproprietary AutoShutdown technologywith robust ESD protection, fastdata rates, and small footprints—basically, everything that you need inan RS-232 transceiver.Multiprotocol transceiversprovide design flexibilityIn cases where the protocols areeither not known in advance orwhere there needs to be flexibility,Maxim’s multiprotocol transceiversallow you to use a single boardlayout to support either RS-232or RS-485 communication. Thissaves time because one design cansupport different market requirements,and each board can simply beprogrammed to the desired protocolduring production.www.maxim-ic.com/smartgrid 29

CommunicationsFeatured productsOFDM-based PLC chipset dramatically improves reliability and network data rateMAX2990/MAX2991 (G3-PLC Lite)BenefitsThe MAX2990 modem and the MAX2991 analog front-end (AFE)comprise a PLC chipset that achieves reliable long-range datacommunications. The MAX2990 is a highly integrated SoC thatcombines the PHY and MAC layers using Maxim’s 16-bit MAXQ®microcontroller core. The MAX2991 is a state-of-the-art, stand-aloneIC that features two-stage automatic gain control (AGC) with a 62dBdynamic range and on-chip programmable filters. Both devicesoperate in the CENELEC, FCC, and ARIB frequency bands.••Robust long-distance transmission––Up to 100kbps data rate at 10kHz to490kHz; 32kbps at 10kHz to 95kHz––Built-in AGC with 62dB dynamic rangeand DC offset cancellation––Includes forward error correction (FEC),CRC16, and CRC32––CSMA/CA controls traffic in multinodenetworks––ARQ enhances data transmission reliability••High integration lowers BOM cost andspeeds design––On-chip band-select filter, VGA, and10-bit ADC for the Rx path––On-chip band-waveform-shaping filter,programmable predriver, and 10-bit DACfor the Tx path••Built-in security protocols preventtampering––Fast DES/3DES engineMAX2990INTERRUPTCONTROLDESENGINECRC32TIMER/PWMOFDM PLC PHYCSMA/ARQUARTSPI TMGPIOI 2 CJTAGMCU (MAXQ)PLC MACRTCWATCHDOGTIMERFLASH32KBDUAL-PORTSRAM4KB x 8SRAM4KBROM5KB x 8REED-SOLOMONVITERBIDECODERREED-SOLOMONCONVOLUTIONALENCODERBPSKDEMODIFFTFFTINSERTPREAMBLEAND CYCLICPREFIXJAMMERCANCELLERAND SYNCAFE SPI INTERFACEVGA1LPFHPFVGA2ADCADAPTATION 1PREDRIVERRECEIVER PATHLPFADAPTATION 2DACIIRFILTERSERIAL INTERFACETRANSMITTER PATHPROCESS TUNING BLOCKMAX2991CONTROL REGISTERSBlock diagrams of the MAX2990 and MAX2991.30 Maxim Smart Grid Solutions

CommunicationsFeatured productsWi-Fi transceivers enable communication over the longest distancesMAX2830/MAX2831/MAX2832The MAX2830/MAX2831/MAX2832 Wi-Fi RF transceivers supportwireless communication standards in the unlicensed 2.4GHzfrequency band. Maxim’s line of Wi-Fi products are direct-conversion,zero-IF OFDM transceivers providing best-in-class performance tosupport the longest distances. Custom frequency bands for nonstandardand multimode applications are also available.Benefits••Transceivers support industrystandards for easier, faster design––Support for the IEEE 802.11b/g standardsto leverage a large ecosystem of HANdevices••Low noise and high sensitivity enablelarger networks––Low noise figure (2.6dB) and receivesensitivity (-76dBm) enable the longestrange••On-chip filters eliminate external SAWfilter and reduce BOM count and cost––Integrated PA with +18.5dBm transmitpower reduces BOM count and PCB areaWi-FiTRANSCEIVER90°0°PLLOSCBlock diagram of Maxim’s Wi-Fi transceivers.32 Maxim Smart Grid Solutions

CommunicationsFeatured productsWiMAX transceivers boost range and throughput for faster data accessMAX2839/MAX2842BenefitsThe MAX2839/MAX2842 WiMAX RF transceivers provide the flexibilityto support wireless communication standards in the licensed2GHz and 3GHz frequency bands. Maxim’s WiMAX products aredirect-conversion, zero-IF, MIMO OFDM transceivers that use a dualreceiverarchitecture to maximize data throughput and link range.Custom frequency bands for nonstandard and multimode applicationsare also available.••Best-in-class performance extends linkrange––Lowest noise figure (2.3dB) provideslongest range—18% farther than closestcompetitor••Smallest WiMAX transceiver fits thetightest designs––Tiny 3.6mm x 5.1mm wafer-levelpackage (MAX2839AS)••Complete frequency coverage withMIMO support to reach customersworldwide––2.3GHz to 2.7GHz with 1x2 MIMOsupport (MAX2839)––3.3GHz to 3.9GHz with 2x2 MIMOsupport (MAX2842)WiMAXTRANSCEIVER90°0°PLLOSCBlock diagram of Maxim’ s WiMAX transceivers.www.maxim-ic.com/smartgrid 33

CommunicationsFeatured products260MHz to 470MHz ISM radio for HANs and NANs extends battery life up to seven yearsMAX7032BenefitsThe MAX7032 transceiver offers an inexpensive, low-power solutionfor one-way and two-way reporting from meters in HANs and someNANs. The transceiver uses the license-free low-frequency radiobands in the U.S. (260MHz to 470MHz) and Europe (433.05MHz to434.79MHz). The radio’s simple ASK or FSK modulation technique,outstanding sensitivity, wide selection of data rates, and low currentdrain make it the perfect choice for local radio links and networksin these frequency ranges. The transceiver can achieve link marginsbetter than 120dB, which means that it can reach 1km over open flatterrain or maintain a link between an underground water meter anda local concentrator. The MAX7032 is flexible enough to work withmultiple smart grid communication standards.••Extends battery life––Low active (< 7mA Rx, < 12mA Tx) andshutdown (< 1µA) current extendsbattery life––Programmable receiver shutdown/wake-up cycle for additional currentsavings••Compact radio module for spaceconstrainedmetering applications––Small 5mm x 5mm TQFN package••Good penetration in buildingsMETER SENSOR (WATER ORGAS VOLUME, FLOW, ETC.)µPCRYSTALSCLK DIO CSBTX/RX1DATAMETER OR READERKEYPAD/CONTROLLERANTENNAMATCHINGNETWORKPAOUTLNAINMAX7032TRANSCEIVERHVINAVDDDVDDSUPPLY,BYPASSV DDMETER OR READERDISPLAY4 Ls4 CsLNASRCLNAOUTCERAMICIF FILTERDATA FILTER ANDDETECTOR2 Rs4 CsV DDSystem diagram for the MAX7032.34 Maxim Smart Grid Solutions

CommunicationsFeatured productsLow-/high-band transmitter for HANs/NANs extends battery life up to seven yearsMAX7049*The MAX7049 ASK/FSK transmitter offers an inexpensive, low-powersolution for one-way reporting from meters in HANs and someNANs. The transmitter uses the license-free low- and high-frequencybands in the U.S. and Europe, making it a very flexible solution. Theshaped ASK or FSK modulation technique reduces the transmittedfrequency bandwidth so that more frequency channels can be used.The wide selection of data rates and low current drain make it wellsuited for local radio links and networks. This IC is flexible enoughto work with multiple smart grid communication standards and iscompatible with modes S and T of the European M-Bus standard.Benefits••Extends battery life––Low active (< 35mA) and shutdown(< 0.5µA) current conserves battery life••Low BOM cost––Only crystal and matching componentsare needed••Good penetration in buildings––Maximum allowable Tx power (25mW)for European ETSI standardMETER SENSOR (WATER ORGAS VOLUME, FLOW, ETC.)µPCRYSTALHOP ENABLE SDO SCLK SDICSBDATAINMETER OR READERKEYPAD/CONTROLLERANTENNAMATCHINGNETWORKPA+PA-MAX7049*TRANSCEIVERAVDDDVDDSUPPLY,BYPASSV DDMETER OR READERDISPLAY4 Ls4 CsV DDCPVDD CRTLCPOUTPLL FILTER1 R2 CsSystem diagram for the MAX7049.*Future product—contact the factory for availability.www.maxim-ic.com/smartgrid 35

CommunicationsFeatured productsRF expertise to deliver custom-tailored solutions for your specific smart grid needsASIC ServicesBenefitsMaxim’s ASIC services are available to meet your specific applicationrequirements. Maxim offers flexible engagement options from foundrysales through turnkey design to joint-development projects. Oursmart grid solutions include:••Wireless backhaul; distribution asset management––WiMAX and rebanded WiMAX transceivers••AMR; fault diagnostics––FSK, ASK, OFDM, DSSS transceivers••Maxim’s expertise gives you a highfirst-silicon success rate––Over 15 years of experience in the ASICbusiness––Rich analog and RF IP catalog speedsyour time to market••In-house process technologies provideoptimal performance-cost tradeoff••AMI––WiFi, ZigBee/802.15.4 transceivers••Proprietary solutions––400MHz to 5GHz RF/wireless transceiverswww.maxim-ic.com/ASICs36 Maxim Smart Grid Solutions

CommunicationsFeatured productsMultiprotocol transceivers enable on-the-fly protocol selection for power-metercommunicationsMAX3160E/MAX3161E/MAX3162EBenefitsThe MAX3160E/MAX3161E/MAX3162E are multiprotocol transceiversthat allow designers to use a single device to support both RS-232and RS-485 serial communications in power-meter applications.These devices offer flexibility and convenience through a pinselectableinterface, which makes it easy to program each board tothe desired protocol during production. In addition, the transceivershave extra protection against static electricity; true fail-safe circuitrythat guarantees a logic-high receiver output when the receiverinputs are open or shorted; a 10nA shutdown mode; short-circuitlimiting; and thermal shutdown circuitry to protect against excessivepower dissipation.••Provide adaptability without additionalparts or design work––Pin-programmable half- or full-duplexcommunication––Pin-selectable RS-232 or RS-485/RS-422operation••Save board space and cost––Integrated ±15kV ESD protectioneliminates external protection circuitry––Allow up to 256 transceivers on the buswithout requiring an extra serial bus,UART, or microprocessor••Reduce power consumption––First 3V multiprotocol solution in theindustry––5x lower supply current than thecompetition—significantly reducespower dissipationMAX3160ERS-232DUAL CHARGEPUMPRS-485/RS-422UARTLOGICI/OCONTROLLOGICMULTI-PROTOCOLTRANSCEIVERBLOCKBlock diagram of Maxim’s multiprotocol transceivers.www.maxim-ic.com/smartgrid 37

CommunicationsFeatured productsHighly integrated RS-485 transceivers simplify power-meter interface designsMAX13412E/MAX13413EThe MAX13412E/MAX13413E are half-duplex RS-485/RS-422 transceiversoptimized for isolated power meters. These devices reduce designcomplexity by integrating a low-dropout regulator (LDO) and asensing circuit for AutoDirection control. The internal LDO allowsthe devices to operate from a wide, unregulated voltage range (6Vto 28V), simplifying power-supply designs. AutoDirection controlreduces cost and board space by eliminating an optocoupler inisolated power-meter applications. Other features include enhancedESD protection, fail-safe circuitry, slew-rate limiting, and full-speedoperation.Benefits••AutoDirection control saves cost andboard space––Reduces the number of optical isolatorsneeded in isolated applications••Built-in LDO offers convenience withoutthe worry of providing a regulatedvoltage level––Operates from an unregulated 6V to 28Vpower supply and provides 5V/20mA ofpower to external circuits••Extended ESD level of ±15kV (HumanBody Model) eliminates external ESDprotection circuitry••1/8-unit load receiver input impedanceenables up to 256 peripheral sensors inthe systemV SYSV REGUNREGULATED ISOLATEDPOWER SUPPLY(6V TO 28V)AutoDirection controleliminates thirdoptocouplerRORLDOV CCMCU AND RELATEDCIRCUITRYREDETECTCIRCUITBIntegrated LDO allowswide supply range(6V to 28V)V REGA5V output V REGsupplies up to 20mAto external circuitryV SYSDIDGNDMAX13412E/MAX13413ESystem block diagram of the MAX13412E/MAX13413E.38 Maxim Smart Grid Solutions

CommunicationsRecommended solutionsRecommended solutionsPart Description Features BenefitsRF transceiversMAX2830/31/32MAX2839MAX2842MAX7032MAX7031MAX7030RF transmitterDirect-conversion, zero-IF RF transceivers for2.4GHz 802.11g/bDirect-conversion, zero-IF RF transceiver for2.3GHz to 2.7GHz MIMO WiMAXDirect-conversion, zero-IF RF transceiver for3.3GHz to 3.9GHz MIMO WiMAX300MHz to 450MHz ASK/FSK transceiver withlow current drain300MHz to 450MHz FSK transceiver with lowcurrent drain300MHz to 450MHz ASK transceiver with lowcurrent drainIntegrated PA, antenna diversity switch,and crystal oscillator; best-in-class receivesensitivity (-76dBm)1x2 MIMO RF transceiver with best-in-classnoise figure (2.3dB) and linearity specifications;8mm x 8mm TQFN package2x2 MIMO RF transceiver with best-in-classnoise figure (3.8dB) and linearity specificationsUnder 7mA active receiver current; SPIprogrammable; programmable sleep/wake modeUnder 7mA active receiver current; hardwiredor microprocessor controllable; factory-presetfrequenciesUnder 7mA active receiver current; hardwiredor microprocessor controllable; factory-presetfrequenciesLow-cost, low-BOM implementation for 802.11b/gstandardsBest-in-class performance supports longer range;small package enables compact designsBest-in-class performance supports longer rangeGood in-building range with long battery lifeGood in-building range with long battery lifeGood in-building range with long battery lifeMAX7049*288MHz to 945MHz ASK/FSK transmitter withlow current drainUp to 25mW Tx power; SPI programmable; lessthan 500nA shutdown currentGood in-building range (including800MHz/900MHz) with long battery lifePowerline communications ICsMAX2981/82* Broadband HomePlug 1.0 chipset Up to 14Mbps data transmission Robust, high-data-rate transmission withguaranteed latency for industrial environmentsMAX2990/91(G3-PLC Lite)MAX2991/92*(G3-PLC)Narrowband OFDM PLC chipsetNarrowband OFDM PLC chipsetUp to 100kbps data transmission or lowerdata-raterobust mode for extremely noisyenvironments; DES/3DES encryption engineAES-128 encryption engine; adaptive tonemapping allows coexistence with FSK protocols;6LoWPAN compression enables IPv6Lower network implementation cost from ability tocross transformersLower network implementation cost from ability tocross transformersMultiprotocol transceiversMAX3160EProgrammable 2Tx/2Rx RS-232 or 1Tx/1RxRS-485/RS-422Supports RS-232, RS-422, and RS-485;handles up to 128 devices on the bus; 20-pinSSOPEases system configuration while saving spaceMAX3161EProgrammable 2Tx/2Rx RS-232 or 1Tx/1RxRS-485/RS-422Supports RS-232, RS-422, and RS-485;handles up to 256 devices on the bus; 24-pinSSOPEases system configuration while saving spaceMAX3162EDedicated 2Tx/2Rx RS-232 and 1Tx RS-485/RS-422Supports RS-232, RS-422, and RS-485;handles up to 256 devices on the bus; 28-pinSSOPEases system configuration while saving spaceUARTMAX3107 Single-channel SPI/I 2 C UART Integrated oscillator; 24Mbps data rate; PLL;shutdown modesReduces solution cost and size; offloads μC(Continued on next page)*Future product—contact the factory for availability.www.maxim-ic.com/smartgrid 39

CommunicationsRecommended solutionsRecommended solutions (continued)Part Description Features BenefitsRS-485 transceiversMAX13442E Fault-protected RS-485 transceiver ±80V fault protection; ±15kV ESD protection Eliminates external circuitryMAX13485EMAX3535EMAX13412E/13ERS-485 transceiver with enhanced ESDprotectionIsolated RS-485 transceiver with enhancedESD protectionRS-485 transceivers optimized for isolatedapplications±15kV ESD protection; fail-safe circuitry;hot-swappableRobust ±2.5kV capacitive isolationAutoDirection circuitry; integrated LDOSaves space and provides robust protectionEliminates external optocoupler and power supplyMinimize solution sizeMAX13430E RS-485 transceiver for multivoltage systems Integrated low-voltage logic interface Interfaces directly to low-voltage FPGAs andASICs, eliminating level translatorTransformer driversMAX2531W primary-side transformer H-bridge driverfor isolated suppliesSimple solution for producing an isolated powersupply up to 1WSimple open-loop circuit speeds PSU design,allowing faster time to marketMAX2563W primary-side transformer H-bridge driverfor isolated suppliesSimple solution for producing an isolated powersupply up to 3WSimple open-loop circuit speeds PSU design,allowing faster time to marketPower amplifierMAX22351W autoramping power amplifier for 900MHzapplications+30dBm (1W) typical output power from a 3.6Vsupply or +28dBm from a 2.7V supplyMaximizes read range; operates directly from asingle 2.7V to 5.5V supply, making it suitable foruse with 3-cell NiCd or 1-cell Li+ batteriesDC-DC regulatorMAX15062*36V, 300mA DC-DC regulator with integratedMOSFETLow quiescent current; 2mm x 2mm TDFNpackageHigh integration with small footprint saves upto 50% total board area compared to competingsolutionsAnalog-to-digital converters (ADCs)MAX11103/05 12-bit, 3Msps/2Msps SAR ADCs 73dB SNR; SPI interface; high 1.7MHz full linearbandwidth; 1-channel (SOT23) and 2-channel(μMAX®, TDFN) optionsMAX1379/8312-bit, 1.25Msps, 4-channel, simultaneoussamplingSAR ADCs0 to 5V, 0 to 10V, or ±10V inputs; 70dB SNR;four single-ended or two differential inputs;SPI interfaceTiny SOT23, μMAX, and TDFN packagessave space; serial interface simplifies datatransmissionSerial interface saves cost and space on digitalisolatorsFor a list of Maxim's recommended smart grid communications solutions, please go to: www.maxim-ic.com/communications.40 Maxim Smart Grid Solutions

Energy measurementOverviewEnergy measurementOverviewEnergy demand around the worldis predicted to increase at a ratethat will likely outstrip our abilityto generate it. Estimates by the U.S.Department of Energy forecast totalenergy consumption in the U.S. toincrease by 30% to over 5,000 billionkWh in 2035, while new plannedgeneration (including renewablesources) is expected to grow only22% during this period. Increasedenergy efficiency and improvedenergy management are critical toaverting this potential energy crisis.Traditional open-loop strategies formanaging power usage are crudeand inefficient, resulting in lowerreliability and reduced distributionstability. Engineers are workingto improve power efficiency in allelectronic applications—commercialequipment, home appliances,industrial motors, and networkequipment. Increasing efficiency,however, is only part of the equation.Better energy management and,consequently, comprehensivemeasurement systems are essential.Incorporating feedback abouthow power is consumed yields thebenefits of a closed-loop system andreduces waste. Additionally, givingenergy users greater visibility intotheir power consumption can helpovercome consumer indifference toenergy concerns.Accurate measurement provides thefeedback necessary to understand,confirm, and modify our powerconsumption. It is critical to implementingan energy-managementcontrol loop and providing insight formaintenance and failure diagnostics.This chapter addresses two keyareas that benefit from new energymeasurementtechnologies: residential/commercial point of loads (POLs) anddata centers.Measuring point-of–loadefficiencyIntelligent power-managementschemes require accurate energymeasurement, not only at anaggregate level (e.g., an entirebuilding) but also at the POL (e.g.,air conditioner, lighting, dishwasher,or computer).Smart meters can track time-of-daypower consumption and enableutilities to offer incentives toconsumers to change their usagepatterns. To improve automationwe need to equip consumers withchoices and enhanced services.Individual POLs must be tied to alocal data and control network thatmonitors and allows control of thevarious loads within a buildingor household. Services can beenhanced through power-qualitymeasurements and usage statistics,which can be used to schedulemaintenance. Such a network canbe implemented using a wide varietyof configurations and protocols,depending upon the application.A local data and control network thatincludes accurate power measurementcan enable significant costsavings by identifying how power isbeing used. Consumers who can seethat running the air conditioner costs$200/month (value of use) or quantifythe cost difference between runningthe dryer at noon instead of 7 p.m.(time-value of use) are more likely tochange their usage patterns.Data that used to be acquired byexpensive high-end utility meters isnow available for an order-of-magnitudeless cost. Power factor (PF),harmonic distortion, active power(watts), and apparent power (VA)information can be readily availablefor optimizing power-delivery501.00501.004545WATTS (GREEN) AND VA (BLUE)403530252015100.750.500.25POWER FACTOR (RED LINE)WATTS (GREEN) AND VA (BLUE)403530252015100.750.500.25POWER FACTOR (RED LINE)550SECONDS00SECONDS0Figure 1. The power profile of a laptop computer during power-up, steady-state, and power-down using two different plug-in power supplies.www.maxim-ic.com/smartgrid 41

Energy measurementOverviewbudgets, for predicting maintenance,and for understanding the strain ona system.Figure 1 shows the power consumptionof a laptop computer using twodifferent plug-in power supplies.Even though the actual load is thesame, the power supplied from theline by the utility, called apparentpower, is substantially differentfrom the power consumed by theload, called active power. Suchdifferences lead to unnecessary andunaccounted for power loss. Withenergy-measurement solutions,statistics can be used to adjust deviceoperating behavior to optimizeenergy efficiency.Measurement accuracy is importantto effectively protect against powerfailures and safeguard equipment.Small drops in voltage or linefrequency can indicate pendingpower failure, enabling devicesto switch into a protection mode.Additionally, voltage zero-crossinginformation can be used to timewhen relays should be turned onand off to reduce wear from arcing.Measuring data centerefficiencyData centers are getting a lotof attention. The EnvironmentalProtection Agency (EPA) estimatesthat data centers accounted for 1.5%of U.S. electricity consumption in 2006,and this demand is expected tonearly double by 2011, necessitatingthe development of an additional 10power plants. Increasing data centerenergy efficiency can help avoidthese infrastructural costs, whileoffering data center operators significantsavings on their electricity bills.ENERGY STAR recently releasedguidelines for data centers tomitigate this demand throughincreased energy efficiency. Keyto these guidelines is a new metriccalled power usage effectiveness(PUE), which measures facility infrastructureefficiency. PUE is calculatedby dividing total data center energyconsumption by the IT equipmentenergy consumption. This requiresmetering at multiple locations withinthe data center, including the uninterruptiblepower supply (UPS) andpower distribution units (PDUs).Real-time power consumption data isneeded to prevent costly overloadingof breakers, as well as overallocationto equipment in idle or standbymodes. Armed with this information,data center managers can implementoperational strategies for dynamicpower capping and reallocation tomaximize PUE.An added benefit of energy-measurementsystems is that they give datacenter managers early failure notificationso that preventative maintenancecan be scheduled. Early-warningnotification provides the extra timeneeded to seamlessly utilize aredundant option before failure.Energy-measurement systems enablecontinuous monitoring of the healthof the power network. This capabilityis especially important as equipmentis sequenced, because it can allowmechanisms that avoid circuitoverloads such as those foundduring a black-start recovery.Energy-measurement SoCsImplementation of intelligent powermanagementalgorithms requires clearrepresentation of both actual powerconsumption and actual demand.This necessitates high accuracy andmultiple metrology functions,including: distortion; active, reactive,and apparent power; energy; RMSvoltage and current; and frequency.This information provides valuablefeedback for improving operatingefficiency, preventing power failure,and facilitating power-up sequencingduring a black start.Measurement accuracy is determinedby resolution, precision, and dynamicrange. Many general-purpose MCUsare limited in their accuracy anddynamic range because of their 10-or 12-bit ADCs. Discrete designs,meanwhile, require multiple components,in-depth knowledge of ACmetering, and extensive developmenttime.Today, SoCs are available thatbring the capabilities of intelligentmetering to individual devices, fromPOLs to PDUs. Advances in manufacturingand design technologyenable the metrology contained ina single SoC to meet critical cost,functionality, robustness, and sizerequirements. Today's state-of-theartSoCs can now be integrated intoserver cabinets, UPSs, AC-DC powermodules, PDUs, smart appliances,and luminaires.Figure 2. A ZigBee®-based outlet-monitoring unit.Figure 2 shows an easy-to-use datacollection system for POLs. Thislow-cost outlet-monitoring unitdemonstrates the capabilities ofthe 78M6612 energy-measurementSoC. It allows users to collecttime-stamped data from a poweroutlet and wirelessly transfer it forgraphical analysis or comparisonto a reference meter.The 78M6612 AC-power-monitoringSoC can measure from 10mA to20A with less than 0.5% measurementerror across a wide -40°Cto +85°C temperature range. Itsonboard 22-bit ADC enables this42 Maxim Smart Grid Solutions

Energy measurementOverviewwide dynamic range and accuracy,allowing the device to detect variousPOL low-power modes. Additionally,the wide dynamic range allows thesame circuitry to monitor a diverserange of applications, providingeconomy-of-scale cost savings.Technical benefits of usingan energy-measurement SoC• Accurate power measurementacross a wide current dynamicrange can be used to confirmdifferent low-power modes. Forexample, a single SoC can measurefrom 10mA to 20A with 0.5%accuracy.• Voltage and line-frequencymeasurements can be used todetermine the appropriate timeto use power, especially whenthe source is not the local utilitysupplier. Small drops in voltage orline frequency are an indication ofpending power failure.• AC-voltage zero crossing canbe used to synchronize whenswitches should be turned off oron—an opportunity that occursevery 8ms to 10ms, depending onthe line frequency.• Statistical data can be collectedto detect early failure of a localAC-DC power-supply module orto provide information about thetype of load that was just pluggedinto the outlet.www.maxim-ic.com/smartgrid 43

Energy measurementFeatured productsA single chip implements a highly integrated outlet-monitoring system, saving thetime, space, and cost of a multichip solution78M6612/78M6613BenefitsThe 78M6612/78M6613 are highly integrated, single-phase AC powermeasurementand monitoring (AC-PMON) ICs for consumer andenterprise applications. While the 78M6612 targets general-purpose ACpower-measurement applications, the 78M6613 provides a simplifiedintegration of single-phase AC power measurement for the powersupplymarket. With accuracy of 0.5% Wh or better over a 2000:1 currentrange and over temperature, each single chip provides the metrologydata typically found in complex, multichip metering systems.Featuring four analog inputs, both devices use Teridian’s SingleConverter Technology® design and an integrated 32-bit computationengine (CE) to measure up to two AC loads or wall outlets. The devicesare highly integrated, which reduces board space and lowers costs.Each includes an 8-bit MPU core with 32KB of embedded flash memory,a UART interface, and multiple GPIOs for easy integration into anypower supply or outlet-monitoring unit. The 78M6612/78M6613consume roughly 30mW under typical operating conditions. The78M6612 is available in 64-pin LQFP and 68-pin QFN lead-free packages,while the 78M6613 is available in a 32-pin QFN lead-free package.Designing with the 78M6612/78M6613 is greatly simplified with acomplimentary suite of development tools. Complete energymeasurementfirmware supports the serial UART interface andsimplifies calibration, configuration, and data extraction. Firmwareoptions are available for emulating I 2 C, PMBus, or SMBus interfacesusing the onboard GPIOs. Firmware can be preloaded during ICmanufacture or modified by customers as needed. Software librariesgreatly expedite the development process.••Single-chip solution provides themetrology accuracy typically found inmultichip metering systems––0.5% Wh accuracy over 2000:1 currentrange and over temperature••Adds intelligence to energy monitoring––Full range of embedded energy diagnostics(power factor, harmonic distortion, voltagesag and dip) for each outlet––Predicts power-supply failures––Intelligent switch relay control, includingzero-crossing detection for each outlet••High integration reduces the bill-ofmaterials(BOM) cost––Monitors two outlets simultaneously––Dual-outlet power reduces cost per outlet––Complete energy-measurementcommunication protocol––Eliminates the need for externalcomponents to boot or load calibrationparameters••Reduces time to market––Software support tools simplify designcycles––No code development is required bythe customer––Complete energy-measurement andhost-interface firmware availableSINGLE-PHASE AC78M6612CALIBRATIONCOMMANDSAC LOADSHUNTOR CTMULTIPLEXERSINGLE CONVERTERTECHNOLOGY ARCHITECTURE2000:1 22-BIT ∆-∑ ADC32-BITREAL-TIMECOMPUTATIONENGINE (CE)8051 MCUSINGLE CLOCK/INSTRUCTION5MHzGPIOsCONFIGURATIONAND RELAY CONTROLTEMPERATURE ANDALARMS STATUSVOLTAGE, CURRENT, ANDLINE FREQUENCY2KB SRAMACTIVE, REACTIVE, ANDAPPARENT POWERTEMP COMPENSATION32KB FLASHUARTPOWER FACTOR ANDPHASE ANGLEINTERFACE-SPECIFIC CODE8051 AC-PMON POST PROCESSING32-BIT CEDiagram of a typical energy-measurement SoC embedded in a single-phase application.44 Maxim Smart Grid Solutions

Energy measurementFeatured products8-channel energy-measurement IC simplifies complex server PDU system design whilereducing costs78M6618BenefitsThe 78M6618 is a highly integrated, single-phase, 8-outlet, powermeasurementand monitoring SoC. It is designed for multichannelpower monitoring in PDUs, smart breakers and relay panels forhomes, and building automation.The 78M6618’s accuracy is 0.5% Wh over a 2000:1 current rangeand over temperature—what one would typically find in multichipmetering systems. It has unprecedented integration in an energymeasurementIC: a 32-bit CE, an MPU core, 128KB flash memory,4KB shared RAM, and an RTC; three low-power modes with internaltimer or external event wake-up; two UARTs; and an I 2 C/MICROWIRE®EEPROM interface or an SPI interface. The SoC also featuresTeridian’s Single Converter Technology design, which incorporatesa 22-bit delta-sigma ADC, 10 analog inputs, digital temperaturecompensation, and a precision voltage reference. With these manycapabilities, the 78M6618 supports a wide range of single-phasemetering applications. Needing very few external components, thissingle chip also greatly reduces the cost of implementing complexPDU systems.A complete array of in-circuit emulation and development toolsassists customers and reduces design time. Metrology libraries arespecifically designed for measurement and switch control of eightsingle-phase AC outlets (same phase). A software development kit,reference designs, and reference manuals expedite development andcertification of power and energy measurement.••Single-chip solution provides themetrology accuracy typically found inmultichip metering systems––0.5% Wh accuracy over 2000:1 currentrange and over temperature••Adds intelligence to energy monitoring––Measures the power factor for each outlet––Predicts power-supply failures––Intelligent switch relay control, includingzero-crossing detection for each outlet••High integration reduces BOM cost––Monitors eight outlets simultaneously––Octal-outlet power reduces cost per outlet––Complete energy-measurementcommunication protocol in a single chip••Shortens time to market––Software support tools simplify designcycles––No code development is required bythe customer––Complete energy-measurement andhost-interface firmware available(Block diagram on next page)www.maxim-ic.com/smartgrid 45

Energy measurementFeatured products8-channel energy-measurement IC simplifies complex server PDU system design whilereducing costs (continued)LIVECT1CT2CT3CT4CT5CT6CT7CT8OUTLET1OUTLET2OUTLET3OUTLET4OUTLET5OUTLET6OUTLET7OUTLET8LIVEAC-DCPOWER SUPPLYNEUTRALNEUTRALVI8I7I6I5I4I3I2I1V3.3A V3.3D GNDA GNDD78M6618DCPOWER FAULTI1I2I3I4I5I6I7I8VAUXV1A/DCONVERTERV REFCOMPARATORTEMPSENSORRAMCOMPUTATIONENGINEFLASH80515MPUREGULATORUARTsI 2 CSPITIMERSRTCV BATTV2.5TX1RX1TX2RX2XINBATTERY(OPTIONAL)CONSOLEEEPROM(OPTIONAL)HOST μC,ADDITIONAL 78M6618sRELAY DRIVERS,7-SEG LCD, ETC.DIGITAL I/OICEOSC/PLLXOUT32kHzBlock diagram of the 78M6618 power- and energy-measurement IC.46 Maxim Smart Grid Solutions

Legal noticesTrademark informationTrademark informationµMAX is a registered trademark of Maxim Integrated Products, Inc.1-Wire is a registered trademark of Maxim Integrated Products, Inc.AutoShutdown is a trademark of Maxim Integrated Products, Inc.CENELEC is a service mark of the European Committee for Electrotechnical Standardization.Echelon is a registered trademark of Echelon Corporation.HomePlug is a registered service mark of HomePlug Powerline Alliance, Inc.IEEE is a registered service mark of the Institute of Electrical and Electronics Engineers, Inc.Innovation Delivered is a registered trademark and registered service mark of Maxim Integrated Products, Inc.Maxim is a registered trademark of Maxim Integrated Products, Inc.MAXQ is a registered trademark of Maxim Integrated Products, Inc.MICROWIRE is a registered trademark of National Semiconductor Corporation.PMBus is a trademark of SMIF, Inc.Single Converter Technology, formerly a trademark of Teridian Semiconductor, is a registered trademark of MaximIntegrated Products, Inc.SPI is a trademark of Motorola, Inc.Wi-Fi is a registered certification mark of Wi-Fi Alliance Corporation.WiMAX is a registered certification mark of the WiMAX Forum.ZigBee is a registered trademark and registered service mark of the ZigBee Alliance.Z-Wave is a registered trademark of Sigma Designs, Inc.www.maxim-ic.com/smartgrid 47

Legal noticesTrademark information48 Maxim Smart Grid Solutions

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