The On Semiconductor 74AC540SC is a buffer/inverter IC designed for 2V to 6V operation. It features 3-state outputs and is housed in a 20-SOIC package.
The On Semiconductor MC74AC540DWG is an octal buffer/line driver with 3-state outputs. It operates within a voltage range of 2V to 6V and has an operating temperature of -40°C to 85°C.