功能：八缓冲器/驱动器(3态) The Harris CD74HC540 and CD74HCT540 are Inverting Octal Buffers and Line Drivers with Three-State Outputs and the capability to drive 15 LSTTL loads. The Harris CD74HC541 and CD74HCT541 are Non-Inverting Octal Buffers and Line Drivers with Three-State Outputs that can drive 15 LSTTL loads. The Output Enables (OE1) and (OE2) control the Three-State Outputs. If either OE1 or OE2 is HIGH the outputs will be in the high impedance state. For data output OE1 and OE2 both must be LOW.