wf1988：
SN74HC244DWRSN74HC244(ACTIVE)具有三态输出的八路缓冲器和线路驱动器Theseoctalbuffersandlinedriversaredesignedspecificallytoimproveboththeperformanceanddensityof3-statememoryaddressdrivers,clockdrivers,andbus-orientedreceiversandtransmitters.The’HC244devicesareorganizedastwo4-bitbuffers/driverswithseparateoutput-enable(OE)\inputs.WhenOE\islow,thedevicepassesnoninverteddatafromtheAinputstotheYoutputs.WhenOE\ishigh,theoutputsareinthehigh-impedancestate.74HC244芯片内部共有两个四位三态缓冲器，使用时可分别以1G和2G作为它们的选通工作信号.当1G和2G都为低电平时，输出端Y和输入端A状态相同；当1G和2G都为高电平时，输出呈高阻态.