TheAD7908/AD7918/AD7928are,respectively,8-bit,10-bit,and12-bit,highspeed,lowpower,8-channel,successiveapproximationADCs.Thepartsoperatefromasingle2.7Vto5.25Vpowersupplyandfeaturethroughputratesupto1MSPS.Thepartscontainalownoise,widebandwidthtrack-and-holdamplifierthatcanhandleinputfrequenciesinexcessof8MHz.
TheconversionprocessanddataacquisitionarecontrolledusingCSandtheserialclocksignal,allowingthedevicetoeasilyinterfacewithmicroprocessorsorDSPs.TheinputsignalissampledonthefallingedgeofCSandconversionisalsoinitiatedatthispoint.Therearenopipelinedelaysassociatedwiththepart.
TheAD7908/AD7918/AD7928useadvanceddesigntechniquestoachieveverylowpowerdissipationatmaximumthroughputrates.Atmaximumthroughputrates,theAD7908/AD7918/AD7928consume2mAmaximumwith3Vsupplies;with5Vsupplies,thecurrentconsumptionis2.7mAmaximum.
Throughtheconfigurationofthecontrolregister,theanaloginputrangeforthepartcanbeselectedas0VtoREFINor0Vto2×REFIN,witheitherstraightbinaryortwoscomplementoutputcoding.TheAD7908/AD7918/AD7928eachfeatureeightsingle-endedanaloginputswithachannelsequencertoallowapreprogrammedselectionofchannelstobeconvertedsequentially.
TheconversiontimefortheAD7908/AD7918/AD7928isdeterminedbytheSCLKfrequency,whichisalsousedasthemasterclocktocontroltheconversion.
