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pulseWireless-power technology,development kit target Chevy VoltGeneral Motors (www.gm.com) hopes tosoon establish theplug-in hybrid Chevy Volt asa technology leader in theeyes of the “green”-car-buyingpublic. Toward that end,GM Ventures (www.gm.com/ventures), the company’s venture-capitalsubsidiary, hasinvested $5 million in Israeli wireless-power-technologystart-upPowermat. The fi rst GM deploymentof the Powermat technologywill be a wireless chargingstation in the 2012 Volt, andthe technology will eventuallyroll out to the Chevy, Buick,GMC, and Cadillac brands. GMannounced the development atlast month’s Consumer ElectronicsShow in Las Vegas, butno demos took place.Wireless power chargingis an apt application for consumerdevices in a car’s cabinbecause, in space-constrainedapplications, you’d like to avoidmyriad chargers and danglingwires. On the other hand, thePowermat technology requiresa receiver for each device, soyou’re basically replacing yourcharger and dangling wire witha $40 receiver, which looks likea rigid cell-phone cover.Powermat currently supportsall iPhone models; the second-and third-generation iPodTouch; all docking iPods; HTCDILBERT By Scott AdamsEvo 4G and HD2; MotorolaDroid X; Nintendo DS Lite andDSi; and Blackberry Tour 9630,Bold 9000/9650/9700 series,Curve 8300/8500/8900/9300series, and Pearl.Powermat is not the onlywireless-charging technologyavailable. The WirelessPower Consortium (www.wirelesspowerconsortium.com), of which Texas Instrumentsis a founding member,last summer released Qi, itsown version of an industry standard.The consortium basedits approach on Fulton Technology’s(www.fultontechnology.The Qi-certifiedbqTesla developmentkit (right) helps developersdesign wirelesspower for plug-inhybrid vehicles, suchas the Chevy Volt(below).com) eCoupled technology.TI last month released what itcalls the industry’s fi rst Qi-certifieddevelopment tools andchip set for wireless power.The $499 bqTesla developmentkit includes the bq500110wireless-power-transmittermanager; the single-input, 5Vbq25046 power-supply IC; andthe MSP430bq1010 wirelesspower-controland -communicationsmicrocontroller.—by Margery Conner▷Powermat,www.powermat.com.▷Texas Instruments,www.ti.com.HIGH-VOLTAGEGATE-DRIVER ICsIMPROVE NOISEIMMUNITYFairchild Semiconductorrecently introduced aseries of high-voltagegate-driver ICs, includingthe two-input, twooutput,high- and low-sideFAN7392 with shutdown;the one-input, two-outputFAN7393 half-bridge withshutdown and controllabledead time; the one-input,two-output FAN73932half-bridge with shutdownand fixed dead-time control;and the two-input,two-output FAN73933half-bridge with controllabledead time. The partssuit use in industrial applications,such as motordriveinverters, distributedpower supplies, andtelecom-system powersupplies.The devices featurea common-mode dV/dtnoise-canceling circuitthat enables stable operationof the high-voltagegate driver under highnoisecircumstances,as well as a level-shiftcircuit that offers highsidegate-driver operationwith negative-floatingsupply-return-voltageswings as high as −9.8Vat a high-side floatingsupplyvoltage of 15V. TheFAN739x series providesstable operation over atemperature range of −40to +125°C. The series alsofeatures floating channelsfor bootstrap operation to600V. The devices sell for$1.52 (1000) each.—by Paul Rako▶Fairchild Semiconductor,www.fairchildsemi.com.02.03.1114 EDN | FEBRUARY 3, 2011